USEFULINFORMATION

USEFUL INFORMATION

MACHINABILITY OF MATERIALS2 Steels

3 Stainless steels

4 Cast iron

5 Aluminium and Magnesium

6 Copper

7 Titanium and Nickel alloys

8 Hard materials > 45 HRC

9 Non-metallic materials

10 Machinability of hard materials vs. softmaterials

11 Materials and machinability

WEAR, GLOSSARY, HARDNESS12 Tool failure modes

13 Types of wear

14 Failure modes and types of wear

15 Failure modes and cutting speed

16 Wear and tool life

17 Multilingual glossary - machining and tools

18 Multilingual glossary - materials

19 Multilingual glossary - symbols

20 Hardness comparisons

1

SU

MM

AR

Y

STEELS2

TOOL MAKER’S TIP:

HSS cutting tools: the most versatile

choice for machiningsteels!

Include resulphurized and rephosphorizedcarbon steels containing less than 0.65%manganese, 0.60% silicon and 0.60%copper. Magnetic steels and leadedsteels are also included.

• Uses: magnetic and electric devicesand numerous other applications.

• Machinability: excellent.

• Uses: buildings, bridges, shafts,axles, pins, bolts, nuts, rods, gears,track links, structural components,carburized parts and cold-headedproducts.

• Machinability: good.

Contain percentages of manganese,silicon, nickel, chromium, molybdenum.

• Uses: bearings, machinery parts,axles, gears, pressure vessels,chains, hand tools, trucks and farmmachinery.

• Machinability: generally good foralloy steels < 850 Mpa. More difficultwhen the strength increases.

Soft steels

< 550 Mpa

Structural steels

and plain carbon steels

< 850 Mpa

Alloy steels

STAINLESS STEELS3

TOOL MAKER’S TIP:

The sharp edges ofHSS cutting tools help prevent work

hardening of stainless steels

Have a ferritic structure sometimeswith a matrix of chromium carbides.

No nickel content, low carboncontent, not hardenable.

• Uses: electronics, automotiveexhausts, material handlingequipment, hot water tanks

• Machinability: low.

Provide superior corrosion resistance.Most widely used stainless steels.

• Uses: electronics, pharmaceuticals,chemical industry, food processingequipment, architectural applications

• Machinability: difficult compared toferritic and martensitic steels.Exhibit good high temperaturestrength, strong work-hardeningtendencies and require greaterpower to machine. Low cuttingspeeds and heavy feeds arerecommended.

And highly alloyed stainless steels.Hybrid of ferritic and austenitic.Mechanical properties combine qualitiesof each component steel type. Duplexsteels combine anti-corrosive andmechanical properties.

• Uses: marine applications, desalinationplants, heat exchangers andpetrochemical plants, structuralparts.

• Machinability: good, for low carbon/low chromium steels. Difficult forhigh carbon martensitic steels dueto their abrasiveness.

Free machining

ferritic stainless steelsAustenitic

stainless steels

Ferritic-austenitic,

ferritic, martensitic,

and precipitation hardeningstainless steels

CAST IRON4

TOOL MAKER’S TIP:

Use TiAlN-coatedHSS cutting tools to

machine cast ironand to avoid

workpiece chippingwhen the tool goes

out Basic low-cost cast iron.

• Uses: brake rotors and brakedrums, head cylinders, cylinderblocks, valve bodies, machine toolframes.

• Machinability: excellent.

Exhibit the best strength, competingwith structural steels in automotiveapplications.

• Uses: camshafts, crankshafts, etc.

• Machinability: good.

• Uses: gears

• Machinability: poor

Grey cast iron

(lamellar graphite

cast iron)

Nodular graphite

cast iron

Hardened

cast iron

ALUMINIUM AND MAGNESIUM5

TOOL MAKER’S TIP:

Use HSS cutting tools to prevent

built-up edges during machining of

aluminium alloys and to produce

thick chips inmagnesium

Pure aluminium(≥ 99% Al) exhibitsexcellent formabilityand resistance tocorrosion.

• Uses: chemicalprocessing, tanks,marine equipment,cooking ustensils,building framesand deep-drawingapplications.

• Machinability:excellent but withcontinuous extralong chips andgumminess.

High strength andgood atmosphericcorrosion resistance.

• Uses: aircraftstructural applications,mobile equipment,pipes and fittings,high pressurehydraulic units,bikes andmotorbikes.

• Machinability: goodto excellent,depending on heattreatment. Easierwith higherhardnesses.

Include the mostwidely used die-casting alloys.

• Uses: cylinderblocks, headcylinders,automotive andaeronautic casings,housings,structural frames,ornamentalcastings.

• Machinability:good.

Consist of forgingand die-castingalloys.

• Uses: brakedrums, pulleys,cylinder liners,forged pistons,complex castings.

• Machinability: onlyfair. Lower withhigher Si content.

Lighter than aluminium.

• Uses: instrumenthousing, portabletools andautomotive casing.

• Machinability: highbut thick chips areneeded to avoidfire hazard.

Unalloyed

aluminiumAluminium

alloys

Aluminiumalloys

5% < Si <10%

Aluminiumalloys

>10% SiMagnesium

COPPER6

TOOL MAKER’S TIP:

Trust in the reliabilityof HSS cutting tools,

for machining copper alloys

• Uses: EDM electrodes, electriccomponents.

• Machinability: good, but gummy.

Brass (5-45% Zn) and bronze (3-20% Sn)

• Uses: electric components,electronics, building equipment,lock parts, automotive valves,micromechanics

• Machinability: good

• Uses: chemical industry, pumpsand valve seats, marineapplications (propellers),desalination plants

• Machinability: medium

Pure copper Copper alloys Aluminium bronze

TITANIUM AND NICKEL ALLOYS 7

TOOL MAKER’S TIP:

TiAlN coated HSS-PM cutting

tools: an efficientchoice for the

machining of titaniumand nickel alloys

(or pure titanium)

Show superior corrosionresistance

• Uses: chemical processingindustry.

• Machinability: moderatework hardening tendencybut require sharp tools,rigid set-ups, low cuttingspeeds, heavy feeds andhigh coolant flow.

Coatings also usefulagainst seizing and gallingtendencies.

(or alpha-beta titanium alloys)

Can be heat treated to veryhigh strength levels.

• Uses: compressor blades,jet engine parts, air frameand space capsule com-ponents, pressure ves-sels, fasteners, helicopterrotor blades.

• Machinability: rigid set-ups, low cutting speedsand high coolant flowrecommended.

(or pure nickel)

Mechanical properties simi-lar to those of carbonsteels. Good to excellentcorrosion resistance .

• Uses: chemicals, cata-lysts, batteries, coins

• Machinability: low speedsrequired due to high tem-peratures during machi-ning. Coatings usefulagainst galling and built-up edges.

Often contain chromium.

Exhibit high strength at hightemperatures with resistanceto oxidation and corrosion.

• Uses: turbine blades,power plant compo-nents, marine uses.

• Machinability: low. Require rigid set-ups andspecially designed cut-ting tools, with TiAlNcoatings.

Unalloyed

titaniumTitanium

alloys

Unalloyed

nickel alloys

Nickel alloys

HARD MATERIALS > 45 HRC

TOOL MAKER’S TIP:

Coated HSS-PMcutting tools: the

«four-wheel drive»solution to machining

hard materials

Alloy steels with high carbon content.

• Uses: cutting and forming dies, punches, rolls, gages, cams and fixtures

• Machinability: poor

8

SUCCESS STORY

Operation • Drilling of through holes Ø 18 mm, depth 25 mm with 5% emulsion onpilar-type drilling machines

Solution: • HSS-PM 5% Co drill with TiAlN coating and special geometry Benefits compared with conventional HSS drills (carbide drills couldnot be used)

- Longer tool life (30 holes)- Higher cutting data (vc 15 m/min, f 0.14 mm/rev)

Wear resistantsteel

600 HB

Tool steels

> 45 HRC

NON-METALLIC MATERIALS9

• Uses: portable phonesand computers,automotive parts, homeappliances, building,packaging

• Machinability: excellent.HSS is the best choice !

• Uses: motor vehicles,boat hulls, storage tanks,electrical componentsand pipe, sportinggoods, aircraft, industrialmachinery, computers

• Machinability: good.Sharp edges of HSStools are efficient againstdelamination combinedwith coatings to resistabrasion. HSS-PM toolsare recommended forthe machining of multi-material components orfor honeycomb parts.

• Uses: crucibles,refractories, furnacehearths, rockets, nuclearpower plants, motorbrushes, electrodes

• Machinability: poor.

• Uses: furniture,construction, toys,musical instruments,kitchen ware

• Machinability: excellent.

Plastics andthermosetting

plastics

Reinforced

plasticsGraphite Wood

MACHINABILITY OF HARD MATERIALS VS. SOFT MATERIALS

Hard, brittle material

• Short chips, moderate temperature

• High normal cutting and feed forces

Requirements: high abrasive wear resistance &compressive residual stress of coating

Soft, ductile material

• Long contact length and high temperature on rake face

• High surface shear forces

• Tendency for built-up edges

Requirements :

+ high chemical wear resistance + best adhesion of coating+ no tendency for sticking

10

cuttingforce

cuttingforce

shearplane

shear plane

feed force feedforce

temperature(shear, friction)

temperature(shear, friction)

800°C500°C

1000°C800°C500°C

MATERIALS AND MACHINABILITY11

TOOL FAILURE MODES12

Abrasive wear

Mechanical wear due tofriction between the pieceand the tool

Thermal stress

Stress due to hightemperatures (400-750°C)

Chemical wear

Migration of atomsbetween the tool and the chip due to hightemperature and pressure

Mechanical stress

Stress due to vibrations,shocks, pressure

Adhesive wear

Combined thermal andchemical wear causedwhen chip removes toolmaterial by «sticking»

TYPES OF WEAR13

Flank wear

Friction between theworkpiece and the flankface of the tool, due toabrasive wear

Plastic deformation

Wear mode where the tooledge is deformed, mainlydue to high temperaturesand partly to highmechanical stresses

Crater wear

Wear mode producing acrater on the cutting faceof the tool, due mainly tochemical wear and partlyto abrasive wear

Chipping

Breakage of small piecesof the tool edges, mainlydue to mechanicalstresses and partly due tothermal stress

Built-up edge

Wear mode where theworkpiece material stickson the tool edge, due toadhesive wear

FAILURE MODES AND TYPES OF WEAR

LEGEND

Main influence

Minor influence

14

Abrasive wear

Thermal stress

Chemical wear

Mechanicalstress

Adhesive wear

Flank wear

Deformation

Crater wear

Chipping

Built-up edge

FAILURE MODES AND CUTTING SPEED

TOOL MAKER’S TIP:

In the ideal cuttingspeed range,

abrasive wear mustbe predominant.

Chemical andadhesive wear must

remain at a low level.

15

Tool wear level

Built-up edge

Adhesivewear

Chemicalwear

Cutting speed

Cutting speed

Cutting edge life

Ideal cutting speed range

Tool lifeAbrasive

wear

WEAR AND TOOL LIFE

TOOL MAKER’S TIP:

Prefer abrasive wearfor a long and

predictable tool life.

16

Wear indicators (VB, KT) Wear evolution

Crater

Crater wearKT

Cutting face Wear indicator(VB for instance)

AdaptationQuick evolution

Slow and steadyevolution

End of tool lifeQuick evolution

Cuttingtime

FlankwearVB

Flank face

MULTILINGUAL GLOSSARY - MACHINING AND TOOLS17

MachiningMachine toolWorkpiece

CoolantWear

ToollifeChip

RoughingFinishing

UsinageMachine-outil

PièceFluide de coupe

UsureDurée de vie

CopeauEbaucheFinition

MetallbearbeitungWerkzeugmaschine

WerkstückKühlemittelAbnutzung

Werkzeug-lebensdauerSpan

SchruppenSchlichten

LavorazioneMacchina utensile

PezzaLubrificante

UsuraDurata di vita

TrucioloSgrossatura

Finitura

MecanizadoMáquina-herramienta

PiezaFluido de corte

DesgasteVida útilViruta

DesbasteAcabado

Cutting toolHigh speed steel

CoatingShank

Cutting edgeCutting tooth

Rake faceFlank face

HelixFlutePitchPoint

Outil de coupeAcier rapideRevêtement

QueueArête de coupe

DentFace de coupe

Face de dépouilleHélice

GoujurePas

Pointe

Werkzeug Schnellstahl

BeschichtungSchaft

SchneidkanteWerkzeugzahn

SpanflächeFreifläche

SpiraleSpannutTeilungSpitze

UtensileAcciai rapidi Rivestimento

CodaSpigolo di taglio

DenteFaccia di taglio

FiancoElica

ScanalaturaPassoPunta

Herramienta de corteAcero rápido Revestimiento

MangoArista de corte

DienteSuperficie de corte

Superficie de incidenciaHeliceRanuraPasoPunta

English French German Italian Spanish

MULTILINGUAL GLOSSARY - MATERIALS18

SteelStainless steel

Tool steelCast iron

AluminiumMagnesium

CopperBrass

BronzeTitaniumNickelZinc

PlasticsFiber reinforced plastics

GraphiteWood

AcierAcier inoxydable

Acier à outilFonte

AluminiumMagnésium

CuivreLaitonBronzeTitaneNickelZinc

PlastiquesPlastiques renforcés

GraphiteBois

StahlRostfreier StahlWerkzeugstahl

EisengussAluminiumMagnesium

KupferMessingBronzeTitanNickelZink

KunstoffeFaserverstärkte Kunststoffe

GraphitHolz

AcciaiAcciai inossidabiliAcciai per utensili

GhiseAlluminioMagnese

RameOttoneBronzoTitanioNichelZinco

PlastichePlastiche rinforzati con fibre

GraffitoLegno

AceroAcero inoxidable

Acero de herramientasFundiciónAluminioMagnesio

CobreLatón

BronceTitanioNiquelZinc

PlásticosPlásticos reforzados con fibras

GrafitoMadera

English French German Italian Spanish

Vc

n

Vf

f

fz

d

z

Q

h

ae

ap

MULTILINGUAL GLOSSARY - SYMBOLS19

Cutting speed

Revolution per minute

Feed speed

Feed per revolution

Feed per tooth

Diameter

Number of teeth

Chip removal rate

Chip thickness

Radial depth of cut

Axial depth of cut

Vitesse de coupe

Vitesse de rotation

Vitesse d’avance

Avance par tour

Avance par dent

Diamètre

Nombre de dents

Débit de copeaux

Epaisseur du copeau

Largeur de passe radiale

Profondeur de passeaxiale

Schnittgeschwindigkeit

Drehzahl

Voschubgeschwindigkeit

Vorschub pro Umdrehung

Vorshub pro Zahn

Durchmesser

Zahnezahl

Zeitspanungsvolumen

Spandicke

Radiale Zustellung

Axiale Zustellung

Velocitá di taglio

Velocitá di rotazione giri

Velocitá di avanzamento

Avanzamento per giro

Avanzamento per dente

Diametro

Numero di denti

Volume truciulo per unitá di tiempo

Spessore truciolo

Larghezza radiale di passata

Profonditá assiale di passata

Velocidad de corte

Número de revolucionespor minuto

Velocidad de avance

Avance per revolución

Avance per diente

Diametro

Número de dientes

Caudal de viruta

Espesor de viruta

Anchura de corte radial

Profundidad de corteaxial

English French German Italian SpanishSymbol

HARDNESS COMPARISONS20

1200110010501000970940920900800860840820800782780760740737720700697690680670667640

71.570.469.869.168.66867.56766.465.965.364.76463.563.362.561.861.76160.16059.759.258.858.757.3

767757745733722712710698684682670656653647638630627601

Rockwell CVickersBrinell

615591569547528508491472455440425410396383372360350339328319309301292284276269

5654.753.552.15149.648.547.145.744.543.141.840.439.137.936.635.534.333.132.130.929.928.827.626.625.4

578565534514495477461444429415401388375363352341331321311302293285277269262255

Rockwell CVickersBrinell

261253247241234228222218212207202196192188182178175171163156150143137132127122117

24.222.821.720.5

248241235229223217212207201197192187183179174170167163156149143137131126121116111

Rockwell C

9998.297.396.495.594.693.892.891.990.7908987.886.8868582.980.878.776.4747269.867.665.7

Rockwell BVickersBrinell

100