forging and sheet metal forming - suranaree university of...

Forging andForging andSheet Metal FormingSheet Metal Forming

Dr. Tapany Udomphol

Automotive Production Engineer

by

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Suranaree University of Technology September 2007

Dr. Tapany Udomphol

School of Metallurgical Engineering

Suranaree University of Technology

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• Introduction to metal forming• Hot and cold working• Deformation geometry• Classification of forging processes• Die design and die materials• Metal flow in forging• Force in metal forging• Forging defects

Outline Part I: Forging of Metals ( )


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• Introduction to metal forming• Hot and cold working• Deformation geometry• Classification of forging processes• Die design and die materials• Metal flow in forging• Force in metal forging• Forging defects


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Outline Part II: Sheet metal forming ( )

• Introduction to sheet metal forming• Sheet metal parts• Classification of sheet metal forming• Forming limit criteria• Defects in formed parts


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• Introduction to sheet metal forming• Sheet metal parts• Classification of sheet metal forming• Forming limit criteria• Defects in formed parts

Introduction to metal formingIntroduction to metal formingT.

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There are a wide range of different metal parts involved in anautomobile production.

www.designchain.com


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encarta.msn.com


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Casting

• Gravity die casting• Pressure die casting• Centrifugal casting• Injection moulding• Rotational moulding

i.e.

• Electrochemical machining• Electrical discharge machining• Single/multiple point cutting• Grinding


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Metalprocessing

Cutting

Forming

Joining

• Electrochemical machining• Electrical discharge machining• Single/multiple point cutting• Grinding

i.e.

• Sheet metal forming• Forging• Rolling• Extrusion• Wire drawing

i.e.

i.e.• Fusion welding (arc, laser,electron beam)

• Solid state welding (friction)•Mechanical joining

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Metal forming

Compressiveforming

Combined tensileand compressive

forming

Tensileforming

Forming bybending

Forming byshearing

Classification of metal formingby subgroups


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Compressiveforming

Combined tensileand compressive

forming

Tensileforming

Forming bybending

Forming byshearing

•Rolling

•Open die forming

•Closed die forming

•Indenting

•Pushing through a die

•Pulling through a die

•Deep drawing

•Flange forming

•Spinning

•Upset bulging

•Stretching

•Expanding

•Recessing

•Bending withlinear toolmotion

•Bending withrotary toolmotion

•Joggling

•Twisting

•Blanking

•Coining


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Forgings


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Forged wheelsHot forming

productForged aluminium

pistons andconnecting rods


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Net shape and metal powder forming products

Powder metalforming parts


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Net shapemetal power

parts

Sinteredmetal parts

Metal injectionmoulding parts

Powder metalforming parts


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Metal Sheet forming productswww.numerica-srl.it

Electromagneticforming of

automotive parts


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Stamped plateswww.mse.eng.ohio-state.edu


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www.ducommunaero.com


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Forging machine

www.macri.it

Hot and cold workingHot and cold workingT.

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• The methods used to mechanically shape metalsinto other product forms.

Workingprocesses

Hot working (0.6-0.8Tm)


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Cold working (< 0.3Tm)

• Primary process• Recrystallisation

• Secondary process• No recrystallisation

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Annealing mechanismsAnnealing mechanismsin cold worked metalsin cold worked metals

• Mechanical properties change dueto temperature after cold working

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Annealing mechanismsAnnealing mechanismsin cold worked metalsin cold worked metals

Ductility

Hardness

Strength

Pro

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es


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Annealing mechanisms in cold worked metals

Recovery Recrystallisation Grain growth

Temperature

Pro

perti

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Cold worked andrecovered

New grains

~0.3Tm ~0.5Tm

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Effects of grain size and strainEffects of grain size and strainon recrystallisation temperatureon recrystallisation temperature


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Schematic of recrystallisation diagram

Smaller grains Better strength/properties

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Effects of grain size and strainEffects of grain size and strainon recrystallisation temperatureon recrystallisation temperature


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Flow stress of aluminium as a function ofstrain at different temperature

Flow curves of Cu Zn28

Flow stress Flow stressTemp Strain rate

Advantages and disadvantagesAdvantages and disadvantagesof hot and cold workingof hot and cold working

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Hot working Cold working

Advantages Advantages

• Stronger• Good surface finish• Good dimensional control• Easy handling

• Low flow stress + high ductility• Pore sealed up• Smaller grains• Softer metals


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Disadvantages Disadvantages

• Stronger• Good surface finish• Good dimensional control• Easy handling

• High deformation• Reduced ductility• Expensive equipment

• Low flow stress + high ductility• Pore sealed up• Smaller grains• Softer metals

• Surface oxidation• Poor dimensional control• Hot shortness• Difficult handling

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Deformation geometryDeformation geometryBiaxial-plane stress condition

Triaxial-plane strain condition

• Two principal stresses, 1 and 2.

• Three principal stresses, 1 , 2 and 3, where 1 > 2 > 3.

• EX: Sheet metal forming

Effect of principal stressesin metal working

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, where 1 > 2 > 3.

Biaxial Triaxial

• EX: Forging, rolling extrusion


Part I:Part I: Forging of metalsForging of metalsT.

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• Forging is the working of metal into a usefulshape by hammering or pressing.

• Primitive blacksmith• Parts ranging in size of a bolt to a turbinerotor.• Most carried out hot, although certain metalsmay be cold-forged.


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• Forging is the working of metal into a usefulshape by hammering or pressing.

• Primitive blacksmith• Parts ranging in size of a bolt to a turbinerotor.• Most carried out hot, although certain metalsmay be cold-forged.

www.eindiabusiness.comwww.prime-metals.com

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Classification of forgingClassification of forgingprocessesprocesses

By equipment

1) Forging hammer or drop hammer2) Press forging


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1) Forging hammer or drop hammer2) Press forging

By process

1) Open - die forging2) Closed - die forging

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Forging machinesForging machines


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Drop hammer

Forging machinesForging machines

Potential energy = mgh

• The energy supplied by the blowis equal to the potential energydue to the weight of the ram andthe height of the fall.


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Potential energy = mgh

• Mass production (60-150 blow / min)• Dies are subject to impact loading

Forging machinesForging machinesT.

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Hydraulic Press forging

• Continuous forming at slower rate• Deeper penetration• Expensive equipment


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• Heat loss from workpiece(long contact)• Die life

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Closed and open die forgingClosed and open die forging

Open-die forging


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Closed-die forging

Impression-dieforging

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OpenOpen--die forgingdie forging

• Flat dies• Simple shape• Large objects.• Pre-forming


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• Simple shape• Large objects.• Pre-forming

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CloseClose--die forging (Impression forging)die forging (Impression forging)

• Workpiece is formed under highpressure in a closed cavity.• Small components• Precision forging• Expensive die


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• Workpiece is formed under highpressure in a closed cavity.• Small components• Precision forging• Expensive die

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Forg

ing

load

Forg

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com

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Die cavitycompletelyfilled

Flash beginsto form

Forging loadForging load


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Forg

ing

load

Forg

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Forging stroke

Flash beginsto form

Dies contactworkpiece

Typical curve of forging load vs. stroke forclosed-die forging.

Flash is the excess metal, whichsquirts out of the cavity as a thickribbon of metal.

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The flash serves two purposes:• Acts as a ‘safety value’ for excess metal.• Builds up high pressure to ensure thatthe metal fills all recesses of the die cavity.

Functions of flashFunctions of flash


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The flash serves two purposes:• Acts as a ‘safety value’ for excess metal.• Builds up high pressure to ensure thatthe metal fills all recesses of the die cavity.

Remark: It is necessary to achieve complete filling of the forging cavitywithout generating excessive pressures against the die that maycause it to fracture.

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ClosedClosed--die designdie design

Considerations• workpiece volume and weight• number of preforming steps and their configuration• flash dimensions in preforming and finishing diesthe load and energy requirement for each forging operation, forexample; the flow stress of the materials, the fictional condition,the flow of the material in order to develop the optimum geometry forthe dies.


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Considerations• workpiece volume and weight• number of preforming steps and their configuration• flash dimensions in preforming and finishing diesthe load and energy requirement for each forging operation, forexample; the flow stress of the materials, the fictional condition,the flow of the material in order to develop the optimum geometry forthe dies.

Shape classificationShape classificationT.

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Die set and forging steps forDie set and forging steps forautomobile engine connecting rodautomobile engine connecting rod

• Preforming of a round piece in an open die arrangement.• Rough shape is formed using a block die.• Finishing die gives final tolerances and surface finish.• Removal of flash (excess metal).


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Steering knuckle FlangeRail

http://www.hirschvogel.de/en/produktionsverfahren/warmumformung.php

See simulation

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General considerationsGeneral considerationsfor preform designfor preform design

• Metal used = Metal preform + Flash.

• Concave radii of the preform > radii on the final forging part.

• Cross section of the preform should be higher and narrower than the

final cross section.

draft angle


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• Shapes with thin and long sections orprojections (ribs and webs) are moredifficult to process due to

• higher surface area per unit volume• increasing friction• temperature effects.

draft angleweb

rib

Some typical nomenclature

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• Smooth metal flow – symmetry dies• Avoid shape change

• Minimum flash to do the job.

• Tapered or drafted to facilitate removal of the finished piece.

• Draft allowance is approximately 3-5o outside and 7-10o inside.

• Counterlock to prevent side thrust.

General considerationsfor preform design


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• Smooth metal flow – symmetry dies• Avoid shape change

• Minimum flash to do the job.

• Tapered or drafted to facilitate removal of the finished piece.

• Draft allowance is approximately 3-5o outside and 7-10o inside.

• Counterlock to prevent side thrust.

CounterlockSide thrust

draft angleweb

rib

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Die materials

• Thermal shock resistance• Thermal fatigue resistance• High temperature strength• High wear resistance• High toughness and ductility• High hardenability• High dimensional stabilityduring hardening• High machinability

Required properties

Die materials: alloyed steels (with Cr,Mo, W, V), tool steels, cast steels or castiron. (Heat treatments such as nitriding orchromium plating)

Forging die

www.nitrex.com


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• Thermal shock resistance• Thermal fatigue resistance• High temperature strength• High wear resistance• High toughness and ductility• High hardenability• High dimensional stabilityduring hardening• High machinability

Die materials: alloyed steels (with Cr,Mo, W, V), tool steels, cast steels or castiron. (Heat treatments such as nitriding orchromium plating)

1) Carbon steels with 0.7-0.85% C areappropriate for small tools and flatimpressions.

2) Medium-alloyed tool steels forhammer dies.

3) Highly alloyed steels for hightemperature resistant dies used inpresses and horizontal forgingmachines.

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Forgingmaterials

Steels Copper and copper alloys Light alloysDIN AISI DIN AISI DIN AISI

Forging dies C70 W2 -

C85 W2 -

60MnSi4 - X30WCrV53 H21 X30WCrV53 -

Die materials


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40CrMnMo7 - X38CrMoV51 H11 X38CrMoV51 H11

X32CrMoV33 H10

Die inserts 55NiCrMoV6 6F2 55NiCrMoV6

56NiCrMoV7 6F3 56NiCrMoV7 6F2

57NiCrMoV77 - 57NiCrMoV77 - 57NiCrMoV77 6F3

35NiCrMo16 -

X38CrMoV51 H11 X30WCrV93 H21 X38CrMoV51 H11

X32CrMoV33 H10 X32CrMoV33 H10 X32CrMoV33 H10

X30WCrV53 - X30WCrV52 - X30WCrV53 -

X37CrMoW51 H12

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To increase die life1) Improving die materials such

as using composite die or2) Using surface coating or self-

lubricating coatingsCurrent forging Future forging

Die life improvement


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Ultra hard surface coatings

• Improve die life.

• Reduce energy input.

• Reduce die-related uptimeand downtime.

• Reduce particulate emissionfrom lubricants.http://www.eere.energy.gov/industry/supporting_industries

/pdfs/innovative_die_materials.pdf

Die failuresDie failuresT.

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Wear (abrasion)

Thermal fatigue

Mechanical fatigue

Permanent deformation


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Wear (abrasion)

Thermal fatigue

Mechanical fatigue

Permanent deformation

• Different parts of dies are liable to permanent deformation and wearresulting from mechanical and thermal fatigue

Metal flow in forgingMetal flow in forgingT.

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Incr

easi

ng re

duct

ion Deformation

bandsassociatedwith plasticinstability.


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Finite element analysis of upsetting an aluminium cylinder

Incr

easi

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Schematic representation of shear bandformation in compression of a cylinder.

Deformationbandsassociatedwith plasticinstability.

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Metal flow in forgingMetal flow in forging


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Fibre structure in forged steels

Grain structure resulting from(a) forging, (b) machining and(c) casting.

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Metal flow in forging

• Identify the neutral surface• Metal flows away from theneutral surface in a directionperpendicular to the die motion.


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• Identify the neutral surface• Metal flows away from theneutral surface in a directionperpendicular to the die motion.

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Cold forging • Forging of nut and bolt

Step I Step II Step III Step IV


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www.qform3d.com

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Cold forging • Forging of nut and bolt

Step I Step II Step III


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www.qform3d.com

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http://www.qform3d.com/en/59.html

Hot forging Titanium alloy being forged at 930oC toproduce preliminary turbine blade pre-form.


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Suck in flaw

www.qform3d.com

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Hot forging •AISI 1040 being forged from a squarebar at 1200oC to produce a shaft.


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• Extensive metal flow into flash• Incomplete fill up at the upper part

www.qform3d.com

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Hot forging • DIN/C43 being forged from a roundbar at 1250oC to produce a shaft fork.


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• Possible die filling with minimumflash used.

www.qform3d.com

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Forging from compact bar

• Powder compact bar of 0.78density being forged.

• The density increases firstin the intermediate area thenspread throughout the crosssection.

www.qform3d.com


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density being forged.

• The density increases firstin the intermediate area thenspread throughout the crosssection.

Forces in metal forgingForces in metal forgingT.

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PF i

r

ri

Friction between two surfaces


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Where= frictional coefficient= the shearing stress at the interface

P = the load normal to the interfaceF = the shearing forceAr= summation of asperity areas in contactp = the stress normal to the interface

ppAA

PF i

r

ri

Forces in metal forgingForces in metal forgingT.

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1. No friction2. Small friction3. Sticky friction

The calculation of forging load can beconsidered in three cases


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1. No friction2. Small friction3. Sticky friction

No frictionNo frictionT.

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ol AP o ….Eq. 2

Do

hoD

h hDhD oo22


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Where P is the compressive forceo is the yield stress of the metal

A is the cross sectional area of the metal.

oo

o

oo hDAh

hDPh

DPp 222

444

….Eq. 3

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p

• Assumption:- no barrelling- small thickness,

Then

- frictional conditions on the topand bottom faces of the diskare a constant coefficient ofCoulomb friction;

• Small friction (homogeneous forging)

Small frictionSmall friction


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p

Where= frictional coefficient= the shearing stress at the interface

p = the stress normal to the interface

…Eq.4

• Assumption:- no barrelling- small thickness,

Then

- frictional conditions on the topand bottom faces of the diskare a constant coefficient ofCoulomb friction;

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X=0 X=a

P

Pmax

Friction hill

o

Small frictionSmall friction

• Small friction(non-homogeneous forging)


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h

P

PXa-a

o

Functions of a metal working lubricant- Reduces deformation load- Increases limit of deformation before fracture- Controls surface finish- Minimises metal pickup on tools- Minimises tool wear- Thermally insulates the workpiece and the tools- Cools the workpiece and/or tools

Small frictionSmall frictionT.

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xahoy 2exp'

….Eq. 5 ‘o

y

ha

o 2exp'

xaho 2exp'

Friction hill

Forging stress


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….Eq. 5

x = ax = 0x = -a

Xa-a

‘o

hap o 1'

_

….Eq. 6

Average forging pressure

a/h Forging pressure

High friction (Sticky friction)High friction (Sticky friction)T.

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….Eq. 7

‘o

y

1'

ha

o

1'

hxa

oFriction hill

Forging stress

1'

hxa

oy


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x = ax = 0x = -a

Xa-a

‘o

….Eq. 8

Average forging pressure

a/h Forging pressure

123

2_

hap o

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Example:

A block of lead 25x25x150 mm3 is pressed between flat dies to a size6.25x100x150 mm3. If the uniaxial flow stress o = 6.9 MPa and = 0.25,determine the pressure distribution over the 100 mm dimension (at x = 0, 25and 50 mm) and the total forging load in the sticky friction condition.

xahoy 2exp

32 oo

32'

Dieter, page 574-575


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xahoy 2exp

32

At the centreline of the slab (x = 0)

MPa43505025.6)25.0(2exp

3)9.6(2

max

Likewise, at 25 and 50 mm, the stress distribution will be 58.9 and 8.0 MParespectively.

oo 32' where

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Example: Dieter, page 574-575

The mean forging load (in the sticky friction condition) is

123

2_

hap o

MPap 8.3915.1250

3)9.6(2_


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MPap 8.3915.1250

3)9.6(2_

We calculate the forging load on the assumption that the stress distributionis based on 100 percent sticky friction. Then

The forging load is P = stress x area= (39.8x106)(100x10-3)(150x10-3)= 597 kN= 61 tonnes.

Defects in forgingDefects in forgingT.

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Fluorescence penetrantreveals Forging laps

files.bnpmedia.com

• Incomplete die filling.

• Die misalignment.

• Forging laps.

• Incomplete forging penetration- shouldforge on the press.

• Microstructural differences resulting inpronounced property variation.

• Hot shortness, due to high sulphurconcentration in steel and nickel.

• Residual stresses


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See simulation

www.komatsusanki.co.jp

• Incomplete die filling.

• Die misalignment.

• Forging laps.

• Incomplete forging penetration- shouldforge on the press.

• Microstructural differences resulting inpronounced property variation.

• Hot shortness, due to high sulphurconcentration in steel and nickel.

• Residual stresses

Forging of automobile partsForging of automobile partsT.

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www.jocmachinery.comwww.jocmachinery.com


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• Metals to be forged• Shape and size• Forging temperature• Strain rate• Forging load• Lubrication

• Die design• Die materials• Die life

Part II:Part II: Sheet metal formingSheet metal formingT.

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• Permanent deformation bycold forming (RT).

• Complex 3D shapes.

• The process is carried out in theplane of sheet by tensile forceswith high ratio of surface areato thickness.

Sheet metal forming


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• Permanent deformation bycold forming (RT).

• Complex 3D shapes.

• The process is carried out in theplane of sheet by tensile forceswith high ratio of surface areato thickness.

• Friction conditions at thetool-metal interface.

•• High rate of productionand formability

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Classification (Base on operation)

Classification of sheetClassification of sheet--metalmetalformingforming


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Stretching Deep drawingBlanking Punching Stretching

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Stamping IroningCoining


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Wiping down a flangeRoll forming of sheetFolding Bending

ToolingToolingT.

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• Punch A convex tool for makingholes by shearing, making surface ordisplacing metal with a hammer.

• Die A concave die (female part).

Basic tools


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• Punch A convex tool for makingholes by shearing, making surface ordisplacing metal with a hammer.

• Die A concave die (female part).

Punches and dies

Punch and die in stamping

Die materials:

• High alloyed steels heattreated for the punches anddies.

Compound and transfer diesCompound and transfer diesT.

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Compound dies

• Several operations in one stroke.• Combined processes and create acomplex product in one shot.• Stamping processes of thin sheets.

www.lyons.com


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• Several operations in one stroke.• Combined processes and create acomplex product in one shot.• Stamping processes of thin sheets.

Transfer dies

• Also called compound dies.• The part is moved from station tostation within the press for eachoperation.

www.deltatooling.co.jp/


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Die set consists of

1) Punch holder2) Die block3) Pilot4) Striper plate


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1) Punch holder2) Die block3) Pilot4) Striper plate

pilot

Schematic diagram of a die set

Forming methodsForming methodsT.

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There are a great variety of sheet metal forming methods,mainly using shear and tensile forces in the operation.

• Progressive forming• Hydroforming• Stretch forming• Explosive forming• Stamping

• Shearing and blanking• Bending and contouring• Spinning process• Deep drawing


T. U

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phol • Progressive forming

• Hydroforming• Stretch forming• Explosive forming• Stamping

• Shearing and blanking• Bending and contouring• Spinning process• Deep drawing

Progressive formingProgressive formingT.

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Die

Stripperplate

Punch

www.hillengr.com


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washers

washer

Die

Strip

Progressive die

• Optimise the material usage.

• Determining factors are

1) volume of production

2) the complexity of the shape

HydroformingHydroformingT.

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• Using Rubber or polyurethane pad as dies.

• Single - action hydraulic press.

• Pressure medium- water or oil.

• Transmits a nearly uniform hydrostatic pressureagainst the sheet.

• Pressure ~ 10 MPa or higher


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• Using Rubber or polyurethane pad as dies.

• Single - action hydraulic press.

• Pressure medium- water or oil.

• Transmits a nearly uniform hydrostatic pressureagainst the sheet.

• Pressure ~ 10 MPa or higher

www.thefabricator.com

Hydroforming

Stretch formingStretch formingT.

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• Using tensile forces, normally for uniform cross section).

• required materials with appreciable ductility.


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www.ducommunaero.com

RamRam

Explosive formingExplosive formingT.

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• Explosive charge is detonated in medium (water) at an appropriatestandoff distance from the sheet blank at a very high velocity.

• The shockwave propagating from the explosion serves as a‘friction-less punch’


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StampingStampingT.

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www.fpi.co.th

• Key factors: data collections on die sets, diefailure and material handling damage and machinefailure to identify weak areas in the stampingprocess.

• Materials require good ductility, workhardening and strength

www.ugs.com/


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Automotive stamped parts

img.alibaba.com

Automobile panel die

Panel, fender, bumper

• Materials require good ductility, workhardening and strength

StampingStampingT.

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• Multi-cone design giving structuralintegrity and rigidity equivalent toa steel beam panel at half the weight,and without cutouts,


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Aluminium inner hood panelwww.psc.edu

Shearing and blankingShearing and blankingT.

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(normally 2-10% thickness)

• Proper clean fracture surface.

• Insufficient ragged fracture surface.

• Excessive greater distortion, greater energyrequired to separate metal.

(a) Proper clearanceRaggedsurface

Clearance


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(normally 2-10% thickness)

• Proper clean fracture surface.

• Insufficient ragged fracture surface.

• Excessive greater distortion, greater energyrequired to separate metal.

Thickness clearance

(b) Insufficient clearance

(c) Excessive clearance

blurr

Raggedsurface

Bending and contouringBending and contouringT.

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Wiper rolls

www.macri.it


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Form block

Clamp

Tension

Clamp

www.lathes.co.uk

Bending and contouringBending and contouringT.

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• Outer surface strained.• Inner surfacecontracted.

b/h biaxiality


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R thickness onbending

b/h biaxiality

Strain, ductility

Cracks occur near thecentre of the sheetSpringback

Spinning processSpinning processT.

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• Deep parts of circular symmetrysuch as tank heads, television cones.

Materials: aluminium and alloys, highstrength - low alloy steels, copper,brass and alloys, stainless steel,


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(a) Manual spinning (b) Shear spinning

Materials: aluminium and alloys, highstrength - low alloy steels, copper,brass and alloys, stainless steel,

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Deep drawingDeep drawing

A cup is subjected tothree different types ofdeformation.

• Shaping flat sheets into cup-shaped articles.Examples: bathtubs, shell cases, automobile panels.


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Lamp cover

Stresses and deformation in a section from a drawn cup

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Deep drawingDeep drawing

Thickness profile of drawn cupClearance > 10-20%thickness.

• Die radius – 10 x sheet thickness.• Punch radius – Clearance between punchand die ~10-20% > sheet thickness.

• Hold-down pressure – ~ 2% of o and u.

• Lubrication of die side.

• Material properties - low yield stress, highwork hardening rates.


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Clearance > 10-20%thickness.

• Die radius – 10 x sheet thickness.• Punch radius – Clearance between punchand die ~10-20% > sheet thickness.

• Hold-down pressure – ~ 2% of o and u.

• Lubrication of die side.

• Material properties - low yield stress, highwork hardening rates.

Forming limit criteriaForming limit criteriaT.

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Major strain 1(%)

Failure100

120

• Stretching of circles into ellipsesafter punching

• Percentage changes in thesestrains are compared in the diagram.


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Grid analysis (a) before (b) after deformation ofsheet.

AK steel

0 20 40 60 80 100

1

2

1

2

A B

Failure

Safe

Minor strain 2(%)-40 -20

20

40

60

80

Forming limit diagram

• Stretching of circles into ellipsesafter punching

• Percentage changes in thesestrains are compared in the diagram.

Defects in formed partsDefects in formed partsT.

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Springback problem

www.bgprecision.com


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Springback problem

Edge condition

Crack near punch & shoulderLocalised necking in a strip in tension

nu 2

~ 55o for an isotropicmaterial in pure tension


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aluminium.matter.org.ukEaring in drawn can


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Stretcher strain in low-carbon steel.

•Radial crack•Surface blemish (orange peel)•Wrinkling•Mechanical fibering

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Processing route

Tool geometry-Die-Punch-Blankholder-Drawbeads-Spacers

Material characteristics-Stress-strain curve-Directionality-Forming criteria-Young’s modulus-Friction

Process parameters-Process steps-Blank outline-Blankholder pressure-Blankholder stiffness-Stress relief cuts-Sheet gauge-Drawbeads-Friction


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www.thefabricator.com

Process parameters-Process steps-Blank outline-Blankholder pressure-Blankholder stiffness-Stress relief cuts-Sheet gauge-Drawbeads-Friction

Forming simulation

Forming

Result

ReferencesReferencesT.

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• Dieter, G.E., Mechanical metallurgy, SI metric Edition, 1988, McGraw-Hill,ISBN 0-07-100406-8

• Edwards, L. and Endean, M., Manufacturing with material, 1998,Butterworth Heinemann, ISBN 0 7506 2754 9.

• Beddoes, J. and Bibbly M.J., Principles of metal manufacturing process,1999, Arnold, ISBN 0-470-35241-8.

• Lange, K., Handbook of metal forming, 1985, R.R Donnelly & SonsCompany, ISBN 0-07-036285-8.

•Lecture notes, Sheffield University, 2003.

•Lecture notes, Birmingham University, 2003.

•Lecture notes, Metal forming processes, Prof Manus Satirajinda.


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• Dieter, G.E., Mechanical metallurgy, SI metric Edition, 1988, McGraw-Hill,ISBN 0-07-100406-8

• Edwards, L. and Endean, M., Manufacturing with material, 1998,Butterworth Heinemann, ISBN 0 7506 2754 9.

• Beddoes, J. and Bibbly M.J., Principles of metal manufacturing process,1999, Arnold, ISBN 0-470-35241-8.

• Lange, K., Handbook of metal forming, 1985, R.R Donnelly & SonsCompany, ISBN 0-07-036285-8.

•Lecture notes, Sheffield University, 2003.

•Lecture notes, Birmingham University, 2003.

•Lecture notes, Metal forming processes, Prof Manus Satirajinda.

forging and sheet metal forming - suranaree university of...

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