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Development of New Magnesium Based
Materials
Using Solidification Route
Submitted By
R K SURAJ
Department of Metallurgical and Materials Engineering,
National Institute of Technology - Trichy, India.
Intern: May – July 2013
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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SUMMARY
Magnesium matrix composites are excellent candidate materials for weight structural application
holding regard to their high specific stiffness, high specific strength, good dimensional stability
and good elevated temperature creep properties. Owing to their inherently low density, good
castability and machinability there has been large interest in Magnesium based alloys due to their
advantages from both the properties as well as the processing counterparts. Thus, this study is to
alloy Magnesium with a material to check for betterment in mechanical properties.
In this study, Pure Magnesium was alloyed with varying concentrations of Fe(powdered form)
using the pathway of Disintegrated Melt Deposition (DMD). For comparison, Pure Magnesium
was also synthesized using DMD technique.
Mechanical Characterization were carried out by conducting tensile, compression, microhardness
and macrohardness tests. The tests revealed an improvement in the 0.2% Yield Strength, Ultimate
Tensile Strength and hardness for 5 wt% Fe.
Fracture surface analysis was carried out on the Tensile fracture surface of the Monolithic Mg and
Composite specimens using the Scanning Electron Microscope (SEM). The fracture surfaces
showed the deformation of Matrix and cleavage type in all the materials analyzed. This indicated
that almost all the materials investigated failed by a predominately mixed mode fracture.
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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ACKNOWLEDGEMENT
I would like to take this opportunity to express my heartfelt thanks to my supervisor, Associate
Professor Manoj Gupta, for giving me the opportunity to work under him.
Mr Sankarnarayanan Seetharaman for his invaluable guidance, advice and patience.
Dr Jayalakshmi for her technical guidance and help in casting.
Mr Thoman Tan, lab officer from NUS Materials Science Laboratory for his great effort in
ensuring that facilities were made available and was instrumental in making the project a success.
Sincere thanks to Mr Juraimi, Mr Khalim and Mr Ng Hong Wei from NUS Materials Science
Laboratory for their technical assistance and efforts rendered.
Mr Lam, Mr Rajah from the NUS Fabrication support centre for their technical guidance in
machining the samples for various characterization tests.
Last but not less, sincere appreciations to Mr Pranav, my intern partner for his support.
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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TABLE OF CONTENT
SUMMARY…………………………………………………………………2
ACKNOWLEDGEMENT…………………………………………….3
1 INTRODUCTION……………………………………………………..9
2 LITERATURE REVIEW
2.1 INTRODUCTION…………………………………………….......................10
2.2 MATRIX SELECTION……………………………………….......................10
2.3 REINFORCEMENT…………………………………………………………10
2.4 PROCESS TECHNIQUE…………………………………………………….11
2.5 SUMMARY…………………………………………………………..............11
3 MATERIALS AND EXPERIMENTAL PROCEDURES
3.1 MATERIALS………………………………………………………………….12
3.2 PRIMARY PROCESSING……………………………………........................12
3.3 SECONDARY PROCESSING………………………………………………..15
3.4 DENSITY AND POROSITY…………………………………………………15
3.5 MICROSTRUCTURAL CHARACTERISTICS
3.5.1 X-RAY DIFFRACTION……………………………………………………...16
3.5.2 SCANNING ELECTRON MICROSCOPE…………………………………..16
3.6 MECHANICAL CHARACTERISTICS
3.6.1 MICROHARDNESS TEST…………………………………………………...17
3.6.2 MACROHARDNESS TEST……………………………………………..........18
3.6.3 TENSILE TEST………………………………………………………………19
3.6.4 COMPRESSION TEST………………………………………………………21
3.6.5 FRACTOGRAPHY...........................................................................................22
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4 RESULTS
4.1 MATERIAL PROCESSING…………………………………………………..23
4.2 DENSITY AND POROSITY MEASUREMENTS…………………...............23
4.3 DISTRIBUTION OF REINFORCEMENT…………………………...............23
4.4 X-RAY DIFFRACTION……………………………………………………....26
4.5 MICROHARDNESS AND MACROHARDNESS TEST……………………26
4.6 TENSION TEST………………………………………………………………26
4.8 COMPRESSION TEST……………………………………………………….27
4.8 FRACTOGRAPHY…………………………………………………………...27
5 DISCUSSION
5.1 PRIMARY PROCESSING…………………………………………………...32
5.2 SECONDARY PROCESSING……………………………………………….32
5.3 DENSITY AND POROSITY………………………………………………....32
5.4 PARTICLE DISTRIBUTION………………………………………………...33
5.5 MICROHARDNESS………………………………………………………….33
5.6 TENSILE TEST PROPERTIES………………………………………………33
5.7 FRACTOGRAPHY…………………………………………………………...34
6 CONCLUSION………………………………………………………………...35
7 RECOMMENDATIONS……………………………………………………...36
8 REFERRENCES………………………………………………………………37
APPENDIX A: PROCESSING LOG SHEET…………………………………38
APPENDIX B: SETUP FOR DENSITY MEASUREMENT…………………39
APPENDIX C: DENSITY AND POROSITY MEASUREMENT....................40
APPENDIX D: MICROHARDNESS TEST DATA…………….......................42
APPENDIX E: TENSILE SPECIMEN……………………………...................43
APPENDIX F: TENSILE TEST………………………………………………..44
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APPENDIX G: COMPRESSION TEST…………………………...........................................48
APPENDIX H: XRD RESULTS……………………………………………………………....52
LIST OF FIGURES
FIGURE A1: Schematic Methodology………………………………………………………....12
FIGURE B1: Schematic diagram of experimental setup for DMD…………………………….14
FIGURE C1: Sample completely immersed in water during the density measurement………..16
FIGURE D1: JEOL JSM-5600LV Scanning Electron Microscope…………………………….17
FIGURE E1: Indendation being rendered on the specimen……………………………………18
FIGURE E2: Future-Tech Rockwell Type Hardness Tester…………………………………...19
FIGURE F1: The CNC used to machine tensile specimens……………………………………20
FIGURE F2: A view of tensile specimen after machining……………………………………..21
FIGURE F3: A sample undergoing compression test………………………………………….22
FIGURE G1: Representative Optical Micrograph of Mg-5Fe showing distribution of Fe
particles………………………………………………………………………………………….24
FIGURE G2: Representative Optical Micrograph of Mg-15Fe showing distribution of Fe
particles………………………………………………………………………………………….24
FIGURE G3: Representative SEM Micrograph showing void spaces as a result of Fe particles
having left the matrix in Mg-5Fe………………………………………………………………..25
FIGURE G4: Representative SEM Micrograph showing clustering in Mg-15Fe……………...25
FIGURE H1: Macroscopic view of the fractured sample (Mg – 10 Fe) showing increased
ductility………………………………………………………………………………………….28
FIGURE H2: Representative SEM micrograph showing brittle mode fracture of Pure Mg……28
FIGURE H3: Representative SEM micrograph showing mixed mode fracture of Mg+5 Fe…..29
FIGURE H4: Representative SEM micrograph showing mixed mode fracture of Mg+10 Fe....29
FIGURE H5: Representative SEM micrograph showing mixed mode fracture of Mg+15 Fe....30
FIGURE H6: Representative SEM micrograph showing shear bands in Mg 5 Fe……………..30
FIGURE H7: Representative SEM micrograph showing shear bands in Mg 10 Fe……………31
FIGURE H8: Representative SEM micrograph showing shear bands in Mg 15 Fe………........31
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FIGURE I1: Schematic setup of the apparatus used for density measurement………………..39
FIGURE J1 :Tensile Specimen Specification…………………………………………………43 FIGURE K1: Tensile Stress strain curve of Pure Mg…………………………………………44
FIGURE K2: Tensile Stress strain curve of Mg-5Fe …………………………………………45
FIGURE K3: Tensile Stress strain curve of Mg-10Fe………………………………………...46
FIGURE K4: Tensile Stress strain curve of Mg-15Fe………………………………………...47
FIGURE K5: Compression Stress strain curve of Pure Mg…………………………………..48
FIGURE K6: Compression Stress strain curve of Mg-5Fe …………………………………..49
FIGURE K7: Compression Stress strain curve of Mg-10Fe………………………………….50
FIGURE K8: Compression Stress strain curve of Mg-15Fe………………………………….51
FIGURE L1: XRD Plot of Mg-5 Fe…………………………………………………………..52
FIGURE L2: XRD Plot of Mg-5 Fe(As cast)…………………………………………………53
FIGURE L3: XRD Plot of Mg-5 Fe(Transverse Direction)………………………………......54
FIGURE L4: XRD Plot of Mg-10 Fe…………………………………………………………55
FIGURE L5: XRD Plot of Mg-10 Fe(As Cast)…………………………………………….....56
FIGURE L6: XRD Plot of Mg-10 Fe(Transverse Direction)………………………………....57
FIGURE L7: XRD Plot of Mg-15 Fe………………………………………………………….58
FIGURE L8: XRD Plot of Mg-15 Fe(As cast)………………………………………………..59
FIGURE L9: XRD Plot of Mg-15 Fe(Transverse Direction)…………………………………60
LIST OF TABLES
TABLE A1: Tabulation of the yield results…………………………………………………..23
TABLE B1: Tabulation of density and porosity measurements………………………………23
TABLE C1: Tabulation showing results of microhardness and macrohardness……………...26
TABLE D1: Tabulation of tensile testing results……………………………………………..26
TABLE D2: Tabulation of compression test results…………………………………………..27
TABLE E1: Processing log sheet of Mg-5Fe…………………………………………………38
TABLE F1: Summary of calculated theoretical densities…………………………………….40
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TABLE G1: Tabulation of the microhardness values…………………………………………42
TABLE H1: Tensile test results of Pure Mg…………………………………………………..44
TABLE H2: Tensile test results of Mg-5Fe…………………………………………………...45
TABLE H3: Tensile test results of Mg-10Fe………………………………………………….46
TABLE H4: Tensile test results of Mg-15Fe………………………………………………….47
TABLE H5: Compression test results of Pure Mg…………………………………………….48
TABLE H6: Compression test results of Mg-5Fe……………………………………………..49
TABLE H7: Compression test results of Mg-10Fe……………………………………………50
TABLE H8: Compression test results of Mg-15Fe……………………………………………51
TABLE I1: XRD Tabulation of Mg-5Fe………………………………………………………52
TABLE I2: XRD Tabulation of Mg-5Fe(As cast)……………………………………………..53
TABLE I3: XRD Tabulation of Mg-5Fe(Transverse Direction)………………………………54
TABLE I4: XRD Tabulation of Mg-10Fe……………………………………………………..55
TABLE I5: XRD Tabulation of Mg-10Fe(As Cast)…………………………………………...56
TABLE I6: XRD Tabulation of Mg-10Fe(Transverse Direction)……………………………..57
TABLE I7: XRD Tabulation of Mg-15Fe……………………………………………………...58
TABLE I8: XRD Tabulation of Mg-15Fe(As cast)…………………………………………….59
TABLE I9: XRD Tabulation of Mg-15Fe(Transverse Direction)……………………………...60
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1 INTRODUCTION
Increasing demand for materials with superior mechanical properties coupled with low density has
intensified research on Magnesium based composites as candidate materials in satisfying the
demands of serveral industries such as structural, aerospace and automotive sectors.
Metal Matrix Composites have superior mechanical properties in comparison to Pure Magnesium.
Owing to an increase in stiffness and mechanical strength with reinforcements, several advanced
hybrid materials have been developed.
Magnesium is rarely used in its pure form. In view of mechanical property betterment, it is alloyed
commonly with Al, Mn, Zn, Zr, Rare Earth metals and Ag. The major limitation of Magnesium is
low elastic modulus and detrimental properties at elevated service temperatures.
Due to the low cost of processing, research has primarily been in the domain of particulate
reinforcements. Also, particulate reinforced metal matrix composite present ease of fabrication
and display isotropic properties.
Previous studies have shown that additions of Metals such as Ni and Titanium have had profound
impact on improving the Tensile properties of Magnesium.
The Disintegrated Melt Deposition (DMD) technique is a hybrid technique incorporating
conventional melt deposition as well as spray forming. Argon gas jets are utilized to break up the
cast slurry before it forms the mold. The technique is known to give uniform distribution of the
alloying elements coupled with minimal porosity and high yield due to which it has been a growing
area of interest in the synthesis of MMCs.
Several systems of Metal Matrix Composites have been analyzed. However, up to date, very
minimal work has gone into the analysis of reinforcing Magnesium with Iron as a reinforcement.
Though Iron is a tramp element in view of corrosion, there is still hope of strengthening.
Thus the objective of the study is to investigate and compare the properties of Magnesium with
Magnesium-Iron Composite. The composites were synthesized by the Disintegrated Melt
Depoistion (DMD) technique, followed by hot extrusion.
Characterization studies such as density and porosity measurements, x-ray diffraction analysis,
scanning electron microscopy, microhardness, macrohardness, tensile and compressive tests were
carried out on the various composites.
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2 LITERATURE REVIEW
2.1 INTRODUCTION
The focus of researching in a particular domain of materials is mainly done in the interest of
seeking practical application in-view of providing material replacement or in rendering changes
so as to bring about improvements in our daily life. Along similar lines, the main industrial sectors
such as automotive, aerospace and structural have procured interest in choosing Magnesium as a
viable candidate material primarily because of their low density, high specific strength, damping
capacity and other desirable mechanical properties. Further improvement in the properties can be
achieved through incorporation of reinforcements which provide enhanced properties in a
collective sense inclusive of strength, modulus, toughness and ductility. In totality, this is the
reason for focusing research on Mg based metal matrix composite systems.
2.2 MATRIX SELECTION
Among the choice of materials to serve as the matrix, owing to its improved mechanical properties
such as high strength to weight ratio, low density, high damping capacity and other desirable
properties, Magnesium has always been a candidate material. Pertaining to metal matrix
composites, previous studies have shown that Magnesium is effective in binding the reinforcement
and also instrumental in effective load transfer. Also, it has been observed that Magnesium based
composites have been in a position to successfully compete with other monolithic alloys such as
Aluminum, Steel and Titanium for weight-critical applications. These are the reasons for choosing
Magnesium as the matrix material in this study.
2.3 REINFORCEMENT
The major disadvantage with Magnesium is limited formability, low elastic modulus, loss of
strength with increase in temperature and limited ductility at room temperature [10][11]. In order
to improve strength, stiffness in a sense generally improve the mechanical properties,
reinforcements are added to serve the primary purpose of carrying load.
The previous studies have seen considerable increase in mechanical properties by using copper as
a reinforcement[3][4].The ductility of Magnesium has also been improved to considerable levels
by the addition of reinforcements such as Titanium[2]. Also, copper has helped in improving other
mechanical properties of Magnesium such as Elastic modulus and Coefficient of Thermal
expansion[6].The addition of Nickel has shown improvements in mechanical strength as well as
cyclic fatigue life[9]. Hybrid reinforcements comprising of particulate as well as nano additions
within the same composite have shown promising results inview of property betterment [5].
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Niobium addition was found to alter mechanical properties to varying (strength and ductility)
extents based on the amount of Niobium addition[8]. Thus, it is a well established fact that different
reinforcements provide varied responses towards matrix property modification owing to which
there is always a surge to investigate different systems and to characterize the behavior of the
same.
2.4 PROCESSING TECHNIQUE
The end properties of the metal matrix composite have a dependency on the processing technique
used for synthesizing them. Several fabrication techniques are present for MMCs. This includes,
infiltration, pressure deposition, spray deposition, semisolid casting and powder metallurgy. The
matrix and reinforcement also play a role in choosing the processing technique.
The Disintegrated Melt Deposition technique(DMD) is capable of producing MMC castings
having uniform distribution of the reinforcement as well as minimal porosity. This technique
overcomes the disadvantages seen in the case of the spray deposition process and in a parallel
sense maintains low cost. Previous research have made it certain that DMD is capable of
processing good quality MMC castings due to which it has been adopted as the processing pathway
for this system of study.
2.5 SUMMARY
From the literature survey it is clear that the characterization and study of the mechanical responses
have been carried out for a wide domain of metallic reinforcements using Magnesium as the matrix
through the DMD technique. However, no work has been done to incorporate Iron as a
reinforcement. Hence, the motive of this work is to study and characterize the change in
mechanical properties by the synthesis of Mg-Fe MMC.
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3 MATERIALS AND EXPERIMENTAL PROCEDURES
In the present study, majority of the tools and equipment were provided by the Materials Science
Laboratory of the Department of Mechanical Engineering, National University of Singapore. The
raw materials used in the experiments were obtained from various suppliers, and they were
weighed and processed prior to casting via the Disintegrated Melt Deposition method. The
deposited ingots were prepared for extrusion into rods by turning them using a lathe machine. The
extruded rods were then sent for further machining to prepare them for experimentation. An
overview is illustrated in figure
FIGURE A1: Schematic Methodology
3.1 MATERIALS
Magnesium Ingot of 99.8% purity(obtained from Tokyo Magnesium company) were used as the
base matrix material. Fe being selected as the reinforcement particle was obtained from. Holes
were drilled on the ingot and filled with the reinforcement particles after weighing.
3.2 PRIMARY PROCESSING
The synthesis of Pure Mg as well as Mg-Fe(containing 5 wt%, 10 wt% and 15 wt% respectively)
was carried out using the DMD technique.
The position of the stainless steel mold was carefully aligned so that the opening at the top of the
mold was in line with the hole at the bottom of the furnace. Two argon gas jets were connected
near to the opening of the mold so as to disintegrate the melt that was to be flowed through.
A graphite crucible with a centrally drilled hole at its base was used to contain the raw materials
during each casting. A nozzle and a plug, both made of graphite, were machined to conform to the
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size of the hole at the bottom of the crucible. This was to ensure that the melt was contained within
the crucible until it was ready to be deposited into the mold. Two stainless steel foils were used to
secure the plug to the nozzle by keeping the plug in place. A long wire was attached to the screw
on the plug to aid in the pulling out of the plug for the melt to flow down into the mold beneath.
The crucible was subsequently placed into the furnace.
A thermocouple and a mild steel stirrer were placed in position before placing the raw materials
into the crucible. After the raw materials were placed in the crucible, the crucible lid, coated with
a layer of graphite, was then placed onto the crucible, after which a ceramic tube that pumps in
argon gas was inserted to create an inert environment during the casting. Insulating materials were
also placed on top of the furnace to provide an enclosed environment and to minimize extensive
heat loss.
The synthesis procedure involved superheating the raw materials to 750ºC using a CAL-9000
controller unit under an inert atmosphere. The inert atmosphere was provided by an inlet argon gas
jet at constant flow rate of 5 L/min. When the temperature of the melt reaches 750ºC, the melt was
stirred at a uniform speed of approximately 450 rpm for around 5 minutes. The stirring was carried
out using a mild steel twin blade stirrer of 45º pitch, coated with a layer of Zirtex 25 (86% ZrO2,
8.8% Y2O3, 3.6% SiO2, 1.2% K2O and Na2O and 0.3% trace organics) to avoid possible iron
contamination. The stirring was done to facilitate the incorporation of the reinforcement particles
in the Mg matrix with a uniform distribution.
At the end of the 5 minutes of stirring, the melt was allowed to flow through the 10 mm centrally
drilled hole of the nozzle by pulling out the graphite plug. The resultant melt stream was
disintegrated using two linear argon gas jets at a distance of 0.20 m from the melt poring point.
The gas flow rate was maintained at 25 L/min. The disintegrated melt slurry was subsequently
deposited onto a circular metallic substrate located around 0.49 m from the gas disintegrated point.
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FIGURE B1: Schematic diagram of experimental setup for DMD
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3.3 SECONDARY PROCESSING
The ingots obtained from the DMD process were machined down from a diameter of 40 mm to a
diameter of approximately 35 mm using the lathe, of which the ingots were subsequently cut into
billets of around 40 mm in height before they were sent for hot extrusion.
Prior to the hot extrusion process, the billets were soaked in a resistance furnace at a temperature
of 400ºC for an hour. The billets were then hot extruded at a temperature of 350ºC with an
extrusion ratio of 26:1, giving 7 mm diameter rods. Extrusion was performed using a 150 ton
hydraulic press with colloidal graphite as lubricant. After extrusion, the extruded rods were
machined to produce tensile specimens. Short sections of the rods of approximately 10 to 15 mm
in height were cut and cleaned of surface graphite to be used for characterization studies.
3.4 DENSITY AND POROSITY MEASUREMENTS
Density measurements were performed to calculate the experimental density and subsequently the
percentage of porosity in the synthesized materials. The extruded rods were cut into smaller
samples using the Precision Diamond Cutting Machine, and further polished to remove any surface
scales or oxides.
Eight samples of each composition were used to obtain their experimental density using
Archimedes Principle by measuring the dry weight and immersed weight. The samples were
weighed in air and when immersed in distilled water, using an A&D ER-182A electronic balance
with an accuracy of ±0.0001g. Porosities within the samples were subsequently calculated from
the mass fractions of the reinforcements, together with the theoretical and experimental densities
of the synthesized materials.
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FIGURE C1: Sample completely immersed in water during the density measurement
3.5 MICROSTRUCTURAL CHARACTERISTICS
3.5.1 X-RAY DIFFRACTION ANALYSIS
X-ray diffraction analysis was conducted using the automated Shimadzu LAB-X XRD-6000 x-ray
diffractometer. Flat, ground and ultrasonically cleaned specimens of approximately 10 mm in
height were exposed to Cu-Kα radiation (λ = 1.54056 Ǻ) with a scanning speed of 2 °/min. The
scanning range was 30° to 80° for all samples. A plot of intensity against 2θ (θ represents Bragg
angle) was obtained, illustrating peaks at different Bragg angles. The Bragg angles corresponding
to different peaks were noted and the values of interplanar spacing (d-spacing) obtained from the
computerised output were compared with the standard values from the International Centre for
Diffraction Data’s Powder Diffraction File (PDF) .
3.5.2 SCANNING ELECTRON MICROSCOPY
The presence and distribution of the iron particles and possible intermetallic phases was
investigated using the JEOL JSM-5600LV Scanning Electron Microscope (SEM). Polished
specimens were observed at 200x,500x and 1000x magnifications. Images were captured at an
accelerating voltage of 15 kV and spot size of 20. The distribution of the particles were also
observed using the FESEM.
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FIGURE D1: JEOL JSM-5600LV Scanning Electron Microscope.
3.6 MECHANICAL CHARACTERISTICS
The mechanical properties of all samples were characterized by carrying out the tensile,
compression, microhardness and macrohardness tests. All tests were carried out at room
temperature and ambient pressure conditions.
3.6.1 MIRCOHARDNESS TEST
Microhardness measurements were carried out to investigate the influence of the addition of Fe
particles on the microhardness of the Mg matrix. Microhardness measurements were conducted
on extruded specimens polished to 0.3µ-finish using Alumina solution to eliminate scratches and
provide a mirror finish surface coupled with flatness.
The microhardness measurements were conducted using an automatic digital microhardness tester
(Matsuzawa MXT50) with a Vickers indenter (with a square-based pyramidal shaped diamond
indenter with face angles of 136º), 980.7 mN test load and a dwell time of 15 seconds. Testing was
done in accordance with ASTM standards E384-08 and E92-82(2003).
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FIGURE E1: Indendation being rendered on the specimen.
3.6.2 MACROHARDNESS TEST
Macrohardness measurements were carried out to investigate the influence of the addition of Fe
particles on the macrohardness of the Mg matrix.The measurements were conducted on extruded
specimens polished to 0.3µ-finish using Alumina solution to eliminate scratches and provide a
mirror finish surface coupled with flatness.
The superficial hardness tests were conducted using an automatic digital macrohardness
tester(Future-Tech Rockwell Type Hardness tester) with a ball indentor and a load of 15Tonnes.
The values obtained were in Rockwell C scale.
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FIGURE E2: Future-Tech Rockwell Type Hardness Tester
3.6.3 TENSILE TEST
The tensile properties of the extruded monolithic Mg and composites samples were performed in
accordance to ASTM test method E8M-08 [16]. An average of five tensile specimens was obtained
from a single rod, and a minimum of four tensile tests were conducted for each sample. Tensile
tests were conducted on round tensile test specimens of diameter 5 mm and gage length 25 mm
using an automated servohydraulic testing machine (MTS). A digital extensometer was attached
to determine the elongation of the specimen.An initial strain rate of 0.254 mm/min was used. All
test specimens were labeled and packed carefully into individual plastic bags to avoid damages to
the fracture surfaces after the testing, which were used to analyze the mode of fracture for the
fractography analysis.
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From the results of the tensile tests, using the Excel spreadsheet, Stress versus Strain curves were
plotted for all the specimens of monolithic Mg and the composites. Using the offset method, the
0.2% yield strength (0.2% YS) of the specimens was obtained from the graphs. The ultimate tensile
strength (UTS) was also obtained directly from the graphs. Ductility was computed from the
percentage elongation of the original gage length of the test specimens. The work of fracture was
then calculated from the area under the stress-strain curves.
FIGURE F1: The CNC machine used to machine tensile specimens
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FIGURE F2: A view of tensile specimen after machining
3.6.4 COMPRESSION TEST
Compression test was carried out on samples of 8mm length and 8mm diameter with perfectly flat
faces using an automated servohydraulic testing machine (MTS) at a strain rate of 0.8 mm/min.
From the results of the compression tests, using the Excel spreadsheet, Stress versus Strain curves
were plotted for all the specimens of monolithic Mg and the composites. Using the offset method,
the 0.2% yield strength (0.2% YS) of the specimens was obtained from the graphs.
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FIGURE F3: A sample undergoing compression test
3.6.5 FRACTOGRAPHY
The fractured surfaces obtained from the tensile and compression tests were cut from the sample
and immediately studied under the JEOL JSM-5600LV Scanning Electron Microscope to
characterize the mode of failure.
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4 RESULTS
4.1 MATERIAL PROCESSING
A total of 3 castings for the composites and one casting for Monolithic Magnesium were processed using the DMD
technique. The deposited ingots got were weighed for the yield obtained.
Composition Mg (Wt%) Fe (Wt%) Yield (%) Status
Pure Mg 100 0 90.58 PASS Mg – 5 Fe 95 5 61.29 PASS Mg – 10 Fe 90 10 57.97 PASS Mg – 15 Fe 85 15 70.61 PASS
TABLE A1: Tabulation of the yield results
4.2 DENSITY AND POROSITY MEASUREMENTS
Results of density and porosity measurements are summarized below,
Composition Theoretical Density (g/cm3)
Experimental Density (g/cm3)
Porosity (%)
Pure Mg 1.7400 1.7266±0.0004 0.77
Mg – 5Fe 1.8274 1.7363±0.0084 4.98
Mg – 10Fe 1.9264 1.7281±0.0152 10.3
Mg – 15Fe 2.0368 1.7701±0.0326 13.1
TABLE B1: Tabulation of density and porosity measurements
4.3 DISTRIBUTION OF REINFORCEMENT
From the polished specimens, the distribution could be observed. Distribution of Fe in the Mg
matrix formed during the DMD process was found to be good.Fe was distributed in the form of
clusters throughout the matrix and the surface integrity between Fe and Mg was found to be poor
owing to formation of oxide layer.
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FIGURE G1: Representative Optical Micrograph of Mg-5Fe showing distribution of Fe particles.
FIGURE G2: Representative Optical Micrograph of Mg-15Fe showing distribution of Fe particles
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FIGURE G3: Representative SEM Micrograph showing void spaces as a result of Fe particles having left the
matrix in Mg-5Fe
FIGURE G4: Representative SEM Micrograph showing clustering of Fe particles in Mg-15Fe
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4.4 X-RAY DIFFRACTION
The results from the X-Ray Diffraction of the samples were analyzed. The lattice spacings (d-
Spacings) obtained was compared to the standard values for Mg, Fe, Fe-Oxides and MgO. The
results confirmed the presence of Mg in monolithic Mg and the composites. However, Fe was not
detected in the Mg-Fe composites. The tabulation of the XRD results have been presented in the
appendix.
4.5 MICROHARDNESS AND MACROHARDNESS TESTS
Results of microhardness and macrohardness tests performed are summarized in Table. The
composites exhibited higher hardness than Monolithic Mg due to the presence of reinforcements.
However, the hardness value dipped on moving from 5% Fe to 15% Fe additions of reinforcement.
Materials Microhardness (HV 0.1) Macrohardness (HRc)
Pure Mg 42.4 ± 1.8 35 ± 1.3
Mg – 5 Fe 64.4 ± 2.8 49.1 ± 1.2
Mg – 15 Fe 49.4 ± 3.2 41.2 ± 1.3
TABLE C1: Tabulation showing results of microhardness and macrohardness
4.6 TENSILE TEST
The summary of the tensile test results are provided in table. The composites showed improved
0.2% Yield Strength (YS) and UTS but coupled with a reduced ductility for 5% Fe and 15% Fe
additions.
Materials 0.2%YS UTS DUCTILITY(%) WOF (MJ/m3)
Pure Mg 95 ± 9 179± 2 11.7± 0.4 19.9 ± 0.6
Mg – 5 Fe 149 ± 3 215 ± 6 8.9 ± 0.7 18.8 ± 1.8
Mg – 10 Fe 125 ± 2 204 ± 15 16.3 ± 2.4 31.7 ± 2.7
Mg – 15 Fe 129 ± 9 175 ± 15 2.6 ± 0.6 4.8 ± 1.4
WOF: Work of Fracture
TABLE D1: Tabulation of tensile testing results
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4.7 COMPRESSION TEST
The summary of the compression test results are provided in table. The composites showed an
improvement in the 0.2% Yield Strength (YS) and Ultimate Compressive Strength.
Materials 0.2% YS UCS Ductility (%) WOF (MJ/m3)
Pure Mg 45 ± 1 305 ± 5 19.5 ± 7.2 39.3 ± 10.3
Mg – 5 Fe 100 ± 4 403 ± 23 15.1 ± 3.8 45 ± 9.4
Mg – 10 Fe 73 ± 2 310 ± 38 20.3 ± 8.2 41.8 ± 16
Mg – 15 Fe 80 ± 3 322 ± 29 17.1 ± 2.3 37.4 ± 6
WOF: Work of Fracture
TABLE D2: Tabulation of compression test results
4.8 FRACTOGRAPHY
SEM micrographs of the fractured tensile and compression samples were taken at different levels
of magnification to analyze the mode of fracture involved.
The macroscopic examination of the fractured sample of Pure Mg revealed predominately Brittle
type fracture while the composites presented a mixed mode of fracture. The same was further
verified by observing the micrographs in which Pure Mg showed only cleavage facets while the
composites played host to matrix deformation, dimples as well as cleavage facets.
The microscopic examination of the fractured compression samples of Pure Mg as well as
composites revealed large number of shear bands signifying varied extents of work hardening.
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FIGURE H1: Macroscopic view of the fractured sample (Mg – 10 Fe) showing increased ductility
(Tensile)
FIGURE H2: Representative SEM micrograph showing brittle mode fracture of Pure Mg
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FIGURE H3: Representative SEM micrograph showing mixed mode fracture of Mg+5 Fe
FIGURE H4: Representative SEM micrograph showing mixed mode fracture of Mg+10 Fe
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FIGURE H5: Representative SEM micrograph showing mixed mode fracture of Mg+15 Fe
(Compression)
FIGURE H6: Representative SEM micrograph showing shear bands in Mg 5 Fe
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FIGURE H7: Representative SEM micrograph showing shear bands in Mg 10 Fe
FIGURE H8: Representative SEM micrograph showing shear bands in Mg 15 Fe
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5 DISCUSSION
5.1 PRIMARY PROCESSING
The DMD technique was successfully employed in the casting of monolithic Mg and the
composites. The DMD technique allowed rapid cooling of the composites by disintegrating the
metal stream using two argon gas jets, resulting in fine grain structure. Homogeneity of the melt
was also achieved through the stirring process, resulting in fine and homogeneously distributed
reinforcements.
During the process, care had to be taken so that the mold and the nozzle were properly aligned to
ensure that a sufficiently high deposited yield could be obtained. Some amount of Fe powder was
added using Magnesium tubings which were placed on the top of the ingot. The reinforcement and
the matrix materials were also being placed in alternate layers in the crucible to provide an initial
wetting to a greater amount of reinforcement particles with the matrix material, thus reducing the
particle settling effect. The deposited ingots showed no macropores or blowholes and there was
minimal oxidation of melt and no detectable reaction between the graphite crucible and melt. These
observations are consistent with the previous findings made on DMD processed magnesium based
composites and verified the suitability of DMD as the primary processing method for this study.
No apparent reaction between the melt slurry and the graphite crucible is primarily attributed to
the inability of Mg to form stable carbides.
5.2 SECONDARY PROCESSING
For the extrusion process, an extrusion temperature of 350ºC with a soaking temperature of 400ºC
and a soaking time of 1 hour were applied to the synthesized materials. The extrusion ratio was set
to 20.25:1 to obtain 8 mm rods. These conditions were selected based on previous studies
conducted, indicating that these parameters were suitable for the successful extrusion of monolithic
Mg and composites. Minimal surface damage was observed on all the extruded rods. The outer
surface of the rod was smooth with no visible defects.
5.3 DENSITY AND POROSITY
The density measurements were carried out using eight samples for each composition taken from
different parts of the extruded rod. The low values of standard deviation are indicative of the face
that the reinforcement has more or less a uniform distribution throughout the matrix. An increase
in density was observed in the case of 15% Fe owing to the increased amount of reinforcement
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value while 5% and 15% Fe showed density close to Monolithic Magnesium for which the possible
reasons include oxidation of Fe and also, reduced amount of Iron impregnation into the matrix
during the casting. Also, all the composites showed increased values of porosity.
5.4 PARTICLE DISTRIBUTION
The FESEM micrographs revealed uniform distribution of particles. A high degree of clustering
was noted along with wide spacing between the reinforcement clusters.
The uniform distribution of reinforcements and intermetallic phases could be a result of
appropriate choice of stirring parameters leading to a fair distribution in the composites and the
redistribution during extrusion as a result of different deformation modes in operation. Good
compatibility of the reinforcement particles with Mg, resulting in better incorporation of the
reinforcement particles into the Mg matrix, could also be the reason for the uniform distribution.
Thus the improved strength of composites in comparison to Monolithic Magnesium can be
attributed to the uniform distribution as observed on the micrograph.
However, the reinforcement particles showed poor surface integrity with the matrix due to
formation of oxide layer owing to Fe.
5.5 MICROHARDNESS
Hardness is defined as the resistance offered by the material to penetration. As the results suggest,
the composites showed higher values of both microhardness as well as macrohardness owing to
the uniform distribution of the reinforcement throughout the matrix. These reinforcements are hard
phases and thus lead to increased resistance to penetration consequently resulting in higher values
of hardness. Similar improvement in microhardness was observed with the addition of Copper
particulates to Magnesium [4].
5.6 TENSILE TEST PROPERTIES
The results in the tensile test showed an improvement in the 0.2% yield strength and ultimate
tensile strength of Pure Magnesium with increasing additions of Fe. This can be attributed to
effective transfer of applied load to the presence of well bonded reinforcements in the matrix. In
general improvement in strength was noted for all three composites. However, the best 0.2% YS
and ultimate tensile strength was observed in Mg-5 wt% Fe composite with 47% and 15% increase
respectively. The decreases in the level of improvement of these properties can be attributed to an
increase in the level of clustering.
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The characterizations revealed an improvement in the ductility only for Mg-10 wt% Fe composite
which can be related to the deformation of ductile Iron particles by means of load transfer from
the matrix thereby delaying the process of fracture and resulting in increased ductility. Similar
observations of an increase in ductility was noted with Titanium[2]. The drastic drop in ductility
associated with Mg – 15 wt% Fe can be correlated with the high level of clustering which might
serve as crack nucleation sites leading to a reduction in ductility during tensile testing.
Work of fracture is defined as the ability of the material to absorb energy before failure under an
applied load. An improvement of 53% in the work of fracture pertaining to Mg – 10 wt% Fe
composite corresponds to the higher ductility presented by the same.
5.7 FRACTOGRAPHY
Macroscopic examination of the fractured tensile specimens showed mixed mode of failure. The
same was seen in the case of SEM micrographs in which the system presented cleavage facets as
well as dimples. Mg-10 wt% Fe showed increased levels of river-like dimples which is
complemented by its comparatively high ductility. Pure Mg however presented predominately
cleavage facets which indicates the inability of Mg to cleave on any single plane. Microcracks
were present predominately in all compositions which is the reason for reduced failure strain.
The compression micrograph in all specimens showed work hardened regions. These were
represented by the presence of shear bands. In the case of compression, during loading, the
reinforcement particles move away from the matrix due to which the properties are reflected by
the behavior of the matrix only. As a result, the various micrographs of the compression samples
showed a similar trend for all compositions.
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6 CONCLUSION
The following are the conclusions that can be drawn from the characterizations carried out on the
systems in this study:
1) Magnesium based composites containing Iron particles can be successfully synthesized by
using the disintegrated melt deposition technique followed by hot extrusion.
2) The SEM micrographs of the various composites showed the presence of reinforcement
clustering with uniform distribution in the matrix.
3) Tensile property characterizations revealed an improvement in the 0.2% YS and UTS for
all compositions. Enhancement in ductility was observed only in the case of Mg-10 wt%
Fe while it was reduced in the other composites.
4) The hardness of Magnesium was enhanced by the addition of Fe as a reinforcement owing
to the distribution of the hard alloying reinforcements.
5) The composites showed a mixed mode of failure by presenting both cleavage facets as well
as river-like dimples in the micrograph.
6) Analysis of the compression fractured samples showed varied levels of work hardening at
different regions within the same sample for all concentrations.
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7 RECOMMENDATIONS
The following are suggestions that could be addressed to improve the results of this study:
1) The reinforcement used in this study was Iron which is a tramp element in view of
Corrosion. Along with Iron, further alloying additions pertaining to corrosion promoters
can be made to investigate the properties and correlate with reinforcements’ susceptibility
to corrosion.
2) The system can be heat treated to investigate the possibility of further increase in
mechanical properties.
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8 REFERENCES
[1] S. Jayalakshmi, Q.B. Nguyen, M. Gupta, Microstructural and mechanical properties of AZ31
magnesium alloy with Cr addition and CO2 incorporation during processing, Department of
Mechanical Engineering, National University of Singapore (NUS), 9 Engineering Drive 1,
Singapore 117576, Singapore.
[2] Hassan, S.F. and M. Gupta, Development of ductile magnesium composite materials using
titanium as reinforcement. Journal of Alloys and Compounds, 2002.
[3] K.F. Ho, M. Gupta T.S. Srivatsan , The mechanical behavior of magnesium alloy AZ91
reinforced with fine copper particulates, Journal of Materials Science and Engineering.
[4] Hassan, S.F and M.Gupta, Development of a novel magnesium-copper based composite with
improved mechanical properties. Department of Mechanical Engineering, National University of
Singapore (NUS), 9 Engineering Drive 1, Singapore 117576, Singapore.
[5] S. Sankaranarayanan, R.K. Sabat, S. Jayalakshmi, S. Suwas, M. Gupta, Effect of hybridizing
micron-sized Ti with nano-sized SiC on the microstructural evolution and mechanical response of
Mg–5.6Ti composite. Department of Mechanical Engineering, National University of Singapore
(NUS), 9 Engineering Drive 1, Singapore 117 576, Singapore,Department of Materials
Engineering, Indian Institute of Science, Bangalore 560 012, India.
[6] S.F. Hassan, K.F. Ho, M. Gupta, Increasing elastic modulus, strength and CTE of AZ91 by
reinforcing pure magnesium with elemental copper. Department of Mechanical Engineering,
National University of Singapore (NUS), 9 Engineering Drive 1, Singapore 117 576, Singapore.
[7] S. Jayalakshmi, S. Sankaranarayanan, S.P.X. Koh, M. Gupta, Effect of Ag and Cu trace
additions on the microstructural evolution
and mechanical properties of Mg–5Sn alloy, Department of Mechanical Engineering, National
University of Singapore (NUS), 9 Engineering Drive 1, Singapore 117 576, Singapore.
[8] M. Shanthi,, P. Jayaramanavar, V. Vyas, D.V.S. Seenivasan, M. Gupta, Effect of niobium
particulate addition on the microstructure and mechanical properties of pure magnesium.Journal
of Alloys and Compounds.
[9] S.F.Hassan, M.Gupta, Development of a novel magnesium/ nickel composite with improved
mechanical properties, Journal of Alloys and Compounds.
[10] D.J. Towle, C.M. Friend, Mater. Sci. Eng. A 188 (1994) 153. [11] A. Martin, J.L. Lorca,
Mater. Sci. Eng. A 201 (1995) 77.
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APPENDIX A : PROCESSING LOG SHEET
Experiment No. 1 20 May 2013
MMC System Mg 5 Fe Pass
Processing Route Disintegrated Melt Deposition (DMD) Technique
Heating Profile: Temperature (°C) vs Time (mins)
RAW MATERIALS
Matrix Initial Mass (g) Form Purity
Mg 716 Billet 99.9+ %
REINFORCEMENTS
Type 1 Fe Type 2 -
Form Powder Form -
Mass (g) 58 Mass (g) -
Wt % 5 Wt % -
Mode of Addition Layered
HEATING TEMPERATURE
Starting Time 1030 Ending Time 1210
Initial Temperature 28 °C Final Temperature 750 °C
APPARATUS
Crucible Type Graphite Impeller Type Mild Steel, Twin
Blade, Pitch 45° Crucible Size A12
Crucible Diameter 125 mm
Impeller Diameter
75 mm Nozzle Size 10 mm
STIRRING CONDITIONS
Stirring Temp. 750 °C Stirrer Position Stirring Time 8mins
15 mm from bottom of crucible Stirring Speed 450 rpm
ARGON SUPPLY
Gas flow rate to crucible 2.5 L/min Gas flow rate to mould 25 L/min
PROCESS PERCENTAGE YIELD
Initial Mass (g) 775
Deposited Mass (g) 475 % Yield (Deposited) 61.29
TABLE E1: Processing log sheet of Mg-5Fe
0
200
400
600
800
0 20 40 60 80 100 120
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APPENDIX B: SCHEMATIC SETUP OF APPARATUS FOR
DENSITY MEASUREMENT
FIGURE I1: Schematic setup of the apparatus used for density measurement
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APPENDIX C: DENSITY AND POROSITY MEASUREMENTS
Using the symbols defined earlier in table ,the total volume of the composite is given by,
𝑉𝐶 = 𝑉𝑀𝑔 + 𝑉𝐹𝑒
⟹𝑊𝐶
𝜌𝐶=
𝑊𝑀𝑔
𝜌𝑀𝑔+
𝑊𝐹𝑒
𝜌𝐹𝑒
Thus, the expression for theoretical density of the composite is given by,
𝜌𝑇ℎ𝑒𝑜𝑟𝑒𝑡𝑖𝑐𝑎𝑙 =1
(𝑊𝑀𝑔
𝜌𝑀𝑔+
𝑊𝐹𝑒
𝜌𝐹𝑒)
SAMPLE CALCULATION
Sample calculation will be based on Mg-15 Fe composition.
𝜌𝑇ℎ𝑒𝑜𝑟𝑒𝑡𝑖𝑐𝑎𝑙 =1
(0.85
1.738+
0.015
7.874) = 2.0367 g/cm3
The table below summarizes the calculated theoretical densities,
Composition Mg (Wt%) Fe (Wt%) Theoretical Density (g/cm3)
Mg – 5 Fe 95 5 1.8273
Mg – 10 Fe 90 10 1.9263
Mg – 15 Fe 85 15 2.0361
TABLE F1: Summary of calculated theoretical densities
CALCULATION FOR EXPERIMENTAL DENSITY
The expression for experimental density is given by,
𝜌𝑒𝑥𝑝 =𝑊𝑎𝑖𝑟𝜌𝑤𝑎𝑡𝑒𝑟 − 𝑊𝑤𝑎𝑡𝑒𝑟𝜌𝑎𝑖𝑟
𝑊𝑎𝑖𝑟 − 𝑊𝑤𝑎𝑡𝑒𝑟
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Where 𝑊𝑎𝑖𝑟 and 𝑊𝑤𝑎𝑡𝑒𝑟 are the weight of specimen in air and water, measured in grams
respectively; 𝜌𝑎𝑖𝑟 and 𝜌𝑤𝑎𝑡𝑒𝑟 are the density of air (0.001225 g/cm3) and water (1 g/cm3)
respectively.
SAMPLE CALCULATION
The following calculation will be based on the composite Mg-15Fe (Specimen 1),
𝜌𝑒𝑥𝑝 =0.6147 𝑥 1−0.2671 𝑥 0.001225
0.6147−0.2671= 1.7676 gm/cm3
POROSITY CALCULATION
The expression for calculating porosity is given by,
𝑃𝑜𝑟𝑜𝑠𝑖𝑡𝑦 =𝜌𝑡ℎ𝑒𝑜 − 𝜌𝑒𝑥𝑝
𝜌𝑡ℎ𝑒𝑜 − 𝜌𝑎𝑖𝑟
SAMPLE CALCULATION
The following calculation will be based on the composite Mg-15 Fe(Specimen 1),
𝑃𝑜𝑟𝑜𝑠𝑖𝑡𝑦 =2.0367 − 1.7676
2.0367 − 0.001225= 13.22%
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APPENDIX D: MICROHARDNESS TEST RAW DATA
The following were the microhardness values obtained for the samples tested:
COMPOSITION 1 2 3 4 5 6 7 8 9 10 11 12 Mean Standard Deviation
Pure Mg 44.7 44.3 42.6 41.6 41.6 44.4 44.3 40.4 42.4 40.6 42.8 39 42.39167 1.82879
Mg – 5 Fe 68.7 62.3 61.9 64.3 69.3 64.1 66.0 65.1 60.2 65.0 61.3 64 64.35 2.76422
Mg – 15 Fe 48.5 48.8 55.1 48.0 47.2 50.7 51.9 50.0 53.1 49.6 42.6 47.7 49.4333 3.18529
TABLE G1: Tabulation of the microhardness values
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APPENDIX E: TENSILE SPECIMEN
Figure J1 : Tensile Specimen Specification
Dimensions and Tolerances:
G – Gauge length : 25.0 ± 0.1 mm
D – Diameter1 : 5.0 ± 0.1 mm
R – Radius of fillet : 5.0
A – Length of reduced section : 30
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APPENDIX F: TENSILE TEST
FIGURE K1: Tensile Stress strain curve of Pure Mg
Specimen No. 0.2 % YS UTS(MPa) Failure Strain(%) WOF (MJ/m3)
1 96 181 11.4 19.5
2 94 178 12 20.4
3 201 201 11.5 22
TABLE H1: Tensile test results of Pure Mg
0
20
40
60
80
100
120
140
160
180
200
0.00% 2.00% 4.00% 6.00% 8.00% 10.00% 12.00% 14.00%
Spec1
Spec2
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FIGURE K2: Tensile Stress strain curve of Mg-5Fe
Specimen No. 0.2 % YS UTS(MPa) Failure Strain(%) WOF (MJ/m3)
1 149 215 8.3 17.5
2 152 220 9.7 20.9
3 146 208 8.8 17.9
4 164 246 6.8 16.5
5 157 235 7.2 16.6
TABLE H2: Tensile test results of Mg-5Fe
0
50
100
150
200
250
0.00% 2.00% 4.00% 6.00% 8.00% 10.00% 12.00%
Spec1
Spec2
Spec3
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FIGURE K3: Tensile Stress strain curve of Mg-10 Fe
Specimen No. 0.2 % YS UTS(MPa) Failure Strain(%) WOF (MJ/m3)
1 126 189 18.8 34.3
2 123 205 16.4 31.8
3 108 196 16.2 30.1
4 112 200 18.8 35.4
5 121 222 1.8 29
6 127 218 13.9 28.9
TABLE H3: Tensile test results of Mg-10Fe
0
50
100
150
200
250
0.00% 5.00% 10.00% 15.00% 20.00% 25.00%
Spec1Spec2Spec6
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FIGURE K4: Tensile Stress strain curve of Mg-15 Fe
Specimen No. 0.2 % YS UTS(MPa) Failure Strain(%) WOF (MJ/m3)
1 131 173 2.3 4.2
2 138 190 3.3 6.4
3 120 161 2.3 3.8
TABLE H4: Tensile test results of Mg-15Fe
0
20
40
60
80
100
120
140
160
180
200
-0.50% 0.00% 0.50% 1.00% 1.50% 2.00% 2.50% 3.00% 3.50% 4.00% 4.50%
Spec1
Spec2
Spec3
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APPENDIX G: COMPRESSION TEST
FIGURE K5: Compression Stress strain curve of Pure Mg
Specimen No. 0.2 % YS UCS(MPa) Failure Strain(%) WOF (MJ/m3)
1 44 309 22.6 41.2
2 46 300 11.2 25.2
3 36 312 21.3 42.3
4 53 314 23.2 62.4
5 68 315 21 46.6
6 45 306 24.5 48.5
TABLE H5: Compression test results of Pure Mg
0
50
100
150
200
250
300
350
-5.00% 0.00% 5.00% 10.00% 15.00% 20.00% 25.00% 30.00%
Spec1
Spec2
Spec6
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FIGURE K6: Compression Stress strain curve of Mg-5Fe
Specimen No. 0.2 % YS UCS(MPa) Failure Strain(%) WOF (MJ/m3)
1 99 402 19.3 55.8
2 97 381 13.8 38.7
3 112 438 11.6 41
4 104 426 12.1 40.6
5 117 431 8.2 39.2
6 75 363 9.7 31.7
TABLE H6: Compression test results of Mg-5Fe
0
50
100
150
200
250
300
350
400
450
0.00% 5.00% 10.00% 15.00% 20.00% 25.00% 30.00%
Spec1
Spec2
Spec4
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FIGURE K7: Compression Stress strain curve of Mg-10Fe
Specimen No. 0.2 % YS UCS(MPa) Failure Strain(%) WOF (MJ/m3)
1 75 339 14.7 39.3
2 49 302 18.3 32.5
3 79 339 18.7 42.3
4 63 289 18.1 30.7
5 72 267 16.6 27.2
6 73 323 29.8 58.8
TABLE H7: Compression test results of Mg-10Fe
0
50
100
150
200
250
300
350
400
0.00% 5.00% 10.00% 15.00% 20.00% 25.00% 30.00% 35.00% 40.00%
Spec1
Spec5
Spec6
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FIGURE K8: Compression Stress strain curve of Mg-15Fe
Specimen No. 0.2 % YS UCS(MPa) Failure Strain(%) WOF (MJ/m3)
1 79 339 14.5 39.3
2 47 302 18.4 32.5
3 79 339 18.7 42.3
4 83 289 18 30.7
5 72 267 16.6 27.2
6 73 323 29.8 58.8
TABLE H8: Compression test results of Mg-15Fe
0
50
100
150
200
250
300
350
400
0.00% 5.00% 10.00% 15.00% 20.00% 25.00%
Spec1
Spec3
Spec4
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APPENDIX H: XRD RESULTS
FIGURE L1: XRD Plot of Mg-5 Fe
2θ Intensity(dps) 2θ Intensity(dps) 32.18 844 67.28 116 34.42 937 68.68 142
36.64 1162 69.96 308 47.88 159 72.44 25
57.36 288 78.04
63.04 198 TABLE I1: XRD Tabulation of Mg-5Fe
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FIGURE L2: XRD Plot of Mg-5 Fe(As cast)
2θ Intensity(dps) 2θ Intensity(dps) 32.2 223 67.54 15
34.2 306 68.7 70
36.64 1205 70.06 54 47.86 145 72.6 17
57.42 132 77.84 37 63.08 168
TABLE I2: XRD Tabulation of Mg-5Fe(As cast)
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FIGURE L3: XRD Plot of Mg-5 Fe(Transverse Direction)
2θ Intensity(dps) 2θ Intensity(dps)
32.2 20 68.62 61 34.49 279 69.92 11
36.66 781 70.02 9 47.84 61 72.5 18
57.36 42 77.2 4
63.06 88 TABLE I3: XRD Tabulation of Mg-5Fe(Transverse Direction)
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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FIGURE L4: XRD Plot of Mg-10 Fe
2θ Intensity(dps) 2θ Intensity(dps) 32.16 889 67.3 104
34.38 438 68.58 132
36.6 1149 69.92 309 47.76 152 72.44 36
57.32 365 78 30 63.1 134
TABLE 1I4: XRD Tabulation of Mg-10Fe
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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FIGURE L5: XRD Plot of Mg-10 Fe(As Cast)
2θ Intensity(dps) 2θ Intensity(dps)
32.16 65 67.28 12 34.42 227 68.62 36
36.64 354 70.06 14 47.86 71 72.72 12
57.38 375 77.94 9 63.06 76
TABLE I5: XRD Tabulation of Mg-10Fe(As Cast)
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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FIGURE L6: XRD Plot of Mg-10 Fe(Transverse Direction)
2θ Intensity(dps) 2θ Intensity(dps)
32.22 37 67.3 6 34.42 250 68.58 37
36.64 302 70.04 18
47.8 74 72.46 17 57.4 22 77.88 7
63.04 98 TABLE I6: XRD Tabulation of Mg-10Fe(Transverse Direction)
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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FIGURE L7: XRD Plot of Mg-15 Fe
2θ Intensity(dps) 2θ Intensity(dps) 32.18 1268 67.24 134
34.38 483 68.68 88
36.6 805 69.94 452 47.9 64 72.6 36
57.32 499 77.8 27 63.08 105
TABLE I7: XRD Tabulation of Mg-15Fe
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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FIGURE L8: XRD Plot of Mg-15 Fe(As cast)
2θ Intensity(dps) 2θ Intensity(dps) 32.2 305 67.32 27
34.42 475 68.6 101
36.64 890 70 248 47.8 199 72.4 27
57.3 49 77.99 15 63.02 100
TABLE I8: XRD Tabulation of Mg-15Fe(As cast)
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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FIGURE L9: XRD Plot of Mg-15 Fe(Transverse Direction)
2θ Intensity(dps) 2θ Intensity(dps) 32.28 25 67.34 7
34.46 393 68.7 40 36.66 262 70.1 12
47.9 61 72.5 32
57.44 16 77.92 6 63.12 103
TABLE I9: XRD Tabulation of Mg-15Fe(Transverse Direction)
DEVELOPMENT OF NEW MAGNESIUM BASED MATERIALS USING SOLIDIFICATION TECHNIQUE
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