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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
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