Group Seminar 2014

Progress on Experimental and Numerical analysis with a special focus on Corevo Foam and Perlite Composite Material (PMC)

2nd October 2014

By: Mohd Ayub Sulong

Supervisors:

Dr. Thomas Fiedler*Prof. Dr. Irina BelovaProf. Dr. Graeme MurchProf. Dr. Andreas Oechsner

*Principal supervisor

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Introduction

Fig. 1: Metal foam made of Zinc and bread roll (Banhart J., 2002)

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Stochastic

3

Introduction

Corevo foam Perlite composite material (PCM) Sintered Titania

Scaffold

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Computed tomography method

Fig. 2: Computed tomography method from raw image to 3D model.

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Introduction

Fig. 3: Corevo or salt foam

Average pore size, d=5.6 mm Average pore

size, d=1.9 mm

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Base Material Properties Corevo Foam: Aluminium alloy - AS7G06 (Al, 7 wt%Si, 0.6 wt%

Mg) Density = 2675kg/m3

Young’s modulus = 74 GPa Poisson’s ratio = 0.33 Yield stress = 241 MPa

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Experimental analysis

Fig. 4: Equivalent plastic strain distribution for (a) d=5.6 mm, sample S#2 (b) d=1.9 mm), sample A (Fiedler et. al, 2014).

ISO 13314 standard

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Failure Analysis

Fig. 5: 0.2% offset yield stress result of sample S#1 and S#2.

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Failure Analysis

Fig. 6: Equivalent plastic strain distribution for (a) d=5.6 mm, sample S#2 (b) d=1.9 mm), sample A (Fiedler et. al, 2014).

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Failure Analysis

Fig. 7: Uni-axial compression test done on Sample S#1

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Failure Analysis

Fig. 8: Experimental compression test snapshots of (a) Corevo® foam samples with an average pore size (d=5.6 mm) , sample S#2 (b) Corevo® foam samples with an average pore size (d=1.9 mm), sample B.

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Introduction

Perlite Composite Material (PCM)

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PMC base material: Aluminium alloy - A356 (7.2 wt% Si, 0.4 wt% Mg, 0.1 wt% Ti, 0.12 wt% Fe) Density = 2.675 g/cm3

Young’s modulus = 75 GPa Poisson’s ratio = 0.33

Expanded perlite (EP) particles Density ≈ 0.1 g/cm3

Young’s modulus = less than 5GPa Composition: 75 wt% SiO2, 14 wt% Al2O3, 3 wt% Na2O, 4 wt% K2O, 1.3 wt%

CaO, 1 wt% Fe2O3, 0.3 wt% MgO, 0.2 wt% TiO2 with traces of heavy metal oxides.

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Sample S 3D view on BoneJ

Fig. 9: Sample S visualised by BoneJ software

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PCM with 3 particle sizes

Fig. 10: Strut’s local thickness distribution for PCM materials.

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Boundary Conditions-PCM

Fig. 11: Mesh sensitivity analysis and boundary conditions used for PCM

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Collapse Mechanism- Treated

Fig. 12: Failure mechanism observed for treated PCM samples

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Fig. 13: Failure mechanism observed for untreated PCM samples

Collapse Mechanism- Untreated

Sample#10

Failure Analysis

Fig. 14: Equivalent plastic strain prediction for PCM with average EP particle size of 3-4 mm (Group M)

Sample#13

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Average stress-strain curves from experiments

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7020406080

100120140

Stress_SStress_MStress_L

Strain ( - )

Stre

ss (

MPa

)

Fig. 15: Experimental average stress-strain data for three groups of EP particle size sample

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Material Properties-Solid samples

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50100200300400500600700800 HT3 Initial YS E_Low E_Literature

Strain ( - )

Stre

ss (

MPa

)

Fig. 16: Experimental average stress-strain data for three groups of EP particle size sample

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Material Properties

-0.0999999999999998 0.1 0.30

100

200

300

400

500

600Piece-wise hardening modulus model

UT_solid_sampleHT3_exp

Strain, -

Stre

ss, M

Pa

E_Exp = 9.8 GpaEquivalent E = 9.8 GPaE_literature = 75 GPa

Fig. 17: Experimental average stress-strain data for three groups of EP particle size sample

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Material Properties

Fig. 18: Experimental average stress-strain data for three groups of EP particle size sample

Numerical result without hardening modulus defined

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Material Properties

Item S M L

Young’s modulus, E (GPa) 12 14 14

Yield Stress 230 230 250

Hardening Modulus, HM y = 10x2 – 3x +1 y = 0.2x +1 y=1

Poisson’s ratio 0.33 0.33 0.33

Fig. 19: Experimental average stress-strain data for three groups of EP

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y = 10x2 – 3x +1

y = 0.2x +1

y=1

Conclusions Corevo foam with two different average pore sizes

have been mechanically characterised. A significant change in plateau stress is observed

between these two group of Corevo foam. Material properties for perlite composite material

are developed using ‘reverse engineering’ method. PCM with different average particle sizes differ

significantly in hardening modulus.

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Q & A Session

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Thanks for your attention

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