The forming The forming characteristics of radial-characteristics of radial-

forward extrusionsforward extrusionsY.S. Lee, S.K. Hwang, Y.S. Chang, B.B. HwangY.S. Lee, S.K. Hwang, Y.S. Chang, B.B. Hwang

Journal of Materials Processing technology, 15 June 2001

Presented by, Douglas Merrell

September 15, 2004

IntroductionIntroduction

The four basis types of extrusion are: The four basis types of extrusion are: direct (forward), indirect (backward), direct (forward), indirect (backward), hydrostatic, and impacthydrostatic, and impact

New types of extrusion are being New types of extrusion are being developed including radial extrusiondeveloped including radial extrusion

IntroductionIntroduction

In conventional extrusions material flows In conventional extrusions material flows parallel to the punch or dieparallel to the punch or die

In radial extrusions the materials flow In radial extrusions the materials flow perpendicular to the punch or dieperpendicular to the punch or die

Examples of Radial Extrusion Examples of Radial Extrusion PartsParts

Radial Extrusion is used to create universal joints, tube fittings and differential gears

IntroductionIntroduction

The researchers developed a model The researchers developed a model using the rigid-finite element methodusing the rigid-finite element method

Using this model they were able to Using this model they were able to simulate changes in design simulate changes in design parametersparameters

Then they were able to determine Then they were able to determine the effect of certain parameters on the effect of certain parameters on the power requirementsthe power requirements

ReferencesReferences[1] S. Kalpakjian, Manufacturing Processes for Engineering Materials, 2[1] S. Kalpakjian, Manufacturing Processes for Engineering Materials, 2ndnd

Edition, Addison-Wesley, USA, 1991, p. 363.Edition, Addison-Wesley, USA, 1991, p. 363.[2] J. A. Pale, T. Altan, Development of equipment and capabilities for [2] J. A. Pale, T. Altan, Development of equipment and capabilities for

investigation of the multi-action forming of complex parts, Eng. Res. Center investigation of the multi-action forming of complex parts, Eng. Res. Center Net Shap Manuf. (1989) 8.Net Shap Manuf. (1989) 8.

[3] M. J. Saran, Journal of Materials Processing Technology. 27 (1991) 279.[3] M. J. Saran, Journal of Materials Processing Technology. 27 (1991) 279.[4] Air Force Materials Laboratory, Forging Equipment, Materials and Practices, [4] Air Force Materials Laboratory, Forging Equipment, Materials and Practices,

Metals and Ceramics Information Center, 1973. p. 164.Metals and Ceramics Information Center, 1973. p. 164.[5] E. Paul De Garmo, Materials and Processes in Manufacturing, Macmillan, [5] E. Paul De Garmo, Materials and Processes in Manufacturing, Macmillan,

New York, 1967, p. 27.New York, 1967, p. 27.[6] E. Paul De Garmo, Material Properties and Manufacturing Processes, [6] E. Paul De Garmo, Material Properties and Manufacturing Processes,

Malloy, Ann Arbor, MI, 1966, p. 31.Malloy, Ann Arbor, MI, 1966, p. 31.[7] J. Datsko, Material Properties and Manufacturing Processes, Malloy, Ann [7] J. Datsko, Material Properties and Manufacturing Processes, Malloy, Ann

Arbor, MI, 1966, p. 31.Arbor, MI, 1966, p. 31.[8] Metals Handbooks, The Materials Information Society, Vol. 2, 10[8] Metals Handbooks, The Materials Information Society, Vol. 2, 10thth Edition, Edition,

p. 104p. 104[9] S. Kobayahi, S.I. Oh, T. Altan, Metal Forming and the Finite Element [9] S. Kobayahi, S.I. Oh, T. Altan, Metal Forming and the Finite Element

Method, Oxford University Press, London, 1989, p. 30.Method, Oxford University Press, London, 1989, p. 30.[10] T. Huziyoshi, Die and Moulding, Daily Tech. Press, Tokyo, 1989, p. 446.[10] T. Huziyoshi, Die and Moulding, Daily Tech. Press, Tokyo, 1989, p. 446.[11] S. H. Lee, Forming characteristics of radial extrusion, Master Dissertation, [11] S. H. Lee, Forming characteristics of radial extrusion, Master Dissertation,

Inhan Graduate School, Inchon, 1999, p. 20.Inhan Graduate School, Inchon, 1999, p. 20.

Model PartModel Part

Billet diameter Billet heightPunch strokeMandrel diameterDie radiusDeflection radiusMandrel radiusGap height

16mm70mm40mm28mm2mm2mm2mm4mm

b = bottom thicknessd0= billet diameterdA= mandrel diameterh0= billet heighth1= workpiece heighthst= punch strokerA = die radiusru = deflection radiusrG = mandrel radiusSs = gap heightSR = annular gap widthSw = wall thickness

Material PropertiesMaterial Properties

Using AA 6063 Aluminum alloy Cold working (strain rate not a factor)

Calculated from σy, E, e, and Su

SimulationSimulation

Maximum pressure is 3257 MPa

SimulationSimulation

Verification that the model matches experimental testsAccurate to within 5%

Design ParametersDesign Parameters

This paper choose to This paper choose to study:study: Mandrel diameter (Mandrel diameter (ddGG)) Die radius (Die radius (rrAA)) Friction factor (Friction factor (mm))

From previous studies [11] From previous studies [11] the gap height was known the gap height was known to have a large effect on to have a large effect on the load. It was held the load. It was held constant.constant.

b = bottom thicknessd0= billet diameterdA= mandrel diameterh0= billet heighth1= workpiece heighthst= punch strokerA = die radiusru = deflection radiusrG = mandrel radiusSs = gap heightSR = annular gap widthSw = wall thickness

Friction FactorFriction Factor

Friction has a large effect after 12.5 mm

Mandrel DiameterMandrel Diameter

Shows the effect of the mandrel diameter on the load requirements.

The greater the diameter the greater the load necessary.

Die radiusDie radius

As the die radius gets larger the force requirements get smaller, but the die radius has the least effect of all the design parameters

ConclusionsConclusions

The friction factor has a large The friction factor has a large influence on the mandrel load but influence on the mandrel load but not on the punch load not on the punch load

The load increases with the mandrel The load increases with the mandrel diameter and the friction factordiameter and the friction factor

The load decreases slightly with an The load decreases slightly with an increase in the die radiusincrease in the die radius

ConclusionsConclusions

The mandrel diameter has the greatest The mandrel diameter has the greatest effect and the die radius has the leasteffect and the die radius has the least

Each of the design parameters had little Each of the design parameters had little effect on the punch loadeffect on the punch load

The punch and mandrel loads are The punch and mandrel loads are similar during the radial extrusion but similar during the radial extrusion but diverge at the start of forward extrusiondiverge at the start of forward extrusion

Questions?Questions?