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Determination of Flow Curves for Bulk Metal Forming

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Abstract

In the simplest case the flow curve is obtained by measuring the force F and the elongation A L in the tensile test. In the range of strain below uniform elongation it is assumed that the stress is constant over the cross-section of the specimen. The ratio F/A where A is the actual cross-section is called flow stress σf:

$$ {\sigma _f} = \frac{F}{A}$$
(2.1)

For the plastic deformation of most metals the condition of volume conservation is fulfilled with good accuracy. Therefore the actual cross-section A can be calculated from the measured elongation:

$$A = \frac{{\pi r_0^2{L_0}}}{{{L_0} + \Delta L}} $$
(2.2)

where L0 is the initial gage length of the test piece. Flow stress is plotted vs. strain

$$ \phi = In\frac{{{L_0} + \Delta L}}{{{L_0}}}$$
(2.3)

The function

$$ {\sigma _t} = {\sigma _f}\left(\phi\right) $$
(2.4)

is called the flow curve. It indicates the stress required for plastic deformation to occur under uniaxial stress. The relation between an uniaxial and a multiaxial state of stress is described by the concepts of equivalent stress and equivalent strain. So in the general case of a triaxial state of stress in Eq. (2.4) φ must be replaced by φ̄.

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Abbreviations

A0 :

initial cross-section of tensile specimen (Figs. 2.5 and 3.1)

A:

actual cross-section of tensile specimen

Amin :

cross-section in the neck of a tensile specimen (beyond uniform elongation)

a:

width of a plane strain upsetting die (Fig. 2.20)

α:

angle of twist in the torsion test

α̇:

time derivate of α

B:

diameter of the head of a torsion test piece (Fig. 2.24)

b:

length of a plane strain upsetting die (Fig. 2.20)

b:

constant in Eq. (2.69)

C:

diameter of the head of a tensile test piece

C:

constant for the absolute magnitude of flow stress in Eq. (2.12) and (2.87)

C:

constant in Eq. (2.74)

C1 :

constant in Eq. (2.56)

c:

specific heat

D1 :

constant in Eq. (2.58)

d:

average grain diameter

d0 :

initial diameter of a tensile test piece (Fig. 2.5)

δ:

factor in Eq. (2.77)

ε:

engineering strain (e.g. relative increase of length in tension test)

et5 :

relative elongation at fracture (total elongation) of a tensile specimen with L0/d0 = 5

εt10 :

relative elongation at fracture (total elongation) of a tensile specimen with L0/d0 = 10

εu :

uniform elongation of a tensile test piece

F:

force

F’:

upsetting force divided through the initial cross-section (Table 2.2)

f(γ, γ̇):

“correction function” for the shape of the flow curve in Eq. (2.57)

f(γr, γ̇r):

averaged “correction function” (Eq. (2.62))

φ:

natural or true strain (log. deformation ratio)

φ0 :

natural strain at the beginning of test

φ1 :

natural strain after the first step of an interrupted upsetting test

Δφ:

increase of natural strain

φ̄d :

equivalent strain determined from diameter measurement in upsetting test

φ̄h :

equivalent strain determined from height measurement in upsetting test

φ̇:

strain rate (time derivate of φ)

φ̇1 :

reference value of φ̇

φ̄̇:

equivalent strain rate

φu :

strain at uniform elongation in tensile test

γ:

(infinitesimal) shear strain

γ̇:

shear strain rate (time derivate of γ)

γu :

shear strain at the radial distance u in a torsion test piece

γ̇u :

shear strain rate at radial distance u in a torsion test piece

γr :

shear strain at the circumference of a torsion test piece

γ̇r :

shear strain rate at the circumference of a torsion test piece

γp :

shear strain at the radial distance up in a torsion test piece

γ̇p :

shear strain rate at the radial distance up in a torsion test piece

G:

limit of error

h0 :

initial height of an upsetting test piece

h:

actual height of an upsetting test piece

h(φ̄):

function, defined by Eq. (2.87)

k = 3,4:

jk

k = 3,4:

coefficients, defined by Eq. (2.63)

k:

constant in the Hall-Petch equation (Eq. (2.7))

kR :

resistance to deformation

L0 :

initial gage length of tensile specimen (Figs. 2.5 and 3.1)

Lc :

length of reduced section of tensile specimen (Figs. 2.5 and 3.1)

Δ L:

increase of length of a tensile test piece

l0 :

length of reduced section of a torsion test piece

lp :

“effective length” of a torsion test piece

M:

torque

M0 :

“zero approximation” of torque

m:

strain rate sensitivity index

μ:

(Coulomb’s) coefficient of friction

ν:

constant in Eq. (2.74)

n:

strain hardening coefficient

n1 :

estimaed value of n

n’:

constant in Eq. (2.74)

Q:

activation energy

ϙ:

densitiy

ϙ:

contour radius of the neck of a deformed tensile test piece

ϙ:

contour radius of an upsetting test piece after bulging

R:

contour radius at the ends of the gage length of a tensile or torsion specimen, see Figs. 2.5, 2.24 and 3.1

R:

gas constant

r0 :

initial radius of a tensile or upsetting test piece

r:

actual radius of a tensile or upsetting test piece

r:

outer radius of a solid or tubular torsion test piece

r :

inner radius of a tubular torsion test piece (r = 0 for solid specimen)

rmax :

maximum radius of an upsetting test piece after bulging

Syl :

lower yield point

Sy∞ :

yield strength for infinite grain size

S:

decrease of height of an upset specimen

ṡ:

time derivate of s

0 :

initial value of s

σ:

normalized “measure of deformation” (Table 2.6)

σik :

components of the stress tensor

T:

temperature

Tm :

melting temperature

t0 :

initial value of the ring height of a Rastegaev test piece (Fig. 2.9)

t:

actual height of the ring

t:

time

τ:

shear stress

u0 :

initial ring width of a Rastegaev test piece (Fig. 2.9)

u:

actual width of the ring

u:

distance from the axis in a torsion test piece

up :

“critical” distance from the axis in a torsion test piece

χ:

coefficient of friction (Coulomb) under the lubricant in the Rastegaev test

X:

“normalized variation of dimensions” (Tables 2.2 and 2.6)

Z:

Zener-Hollomon parameter

Z:

axial coordinate

ω:

relative error

References

  1. (Ed.) Lange, K.: Handbook of Metal Forming (in German), 3 Volumes, Berlin/Heidelberg/New York, Springer 1972–1975.

    Google Scholar 

  2. Stüwe, H.-P.: Flow Curves of Polycrystalline Metals and their Application in the Theory of Plasticity (in German), Z. Metallkde. 56 (1965), pp. 633–642.

    Google Scholar 

  3. Herbertz, R.; Wiegels, H.: The Difference between Tensile and Upsetting Flow Curves as Explained by the Effect of Hydrostatic Stress (in German), Arch. Eisenhiittenwes. 51 (1980), pp. 413–416.

    CAS  Google Scholar 

  4. Dieter, G.E.: Mechanical Metallurgy, 2nd. Ed., New York, McGraw-Hill, 1976.

    Google Scholar 

  5. Dieter, G. E.: Mechanical Behavior of Materials Under Tension, in: (Ed.) Newby, R.: Metals Handbook, Vol. 8, Mechanical Properties, 9th Ed., Metals Park, Ohio, ASM, 1985.

    Google Scholar 

  6. Siebel, E.; Pomp, A.: Further Development of the Compression Test (in German), Mitt. KW1 Eisenforsch. 10 (1928), pp. 55–62.

    Google Scholar 

  7. Reed-Hill, R. E.: Physical Metallurgy Principles, New York, Van Nor-strand Reinhold 1964.

    Google Scholar 

  8. Krause, U.: Comparison of Different Methods for Determining Flow Stress in Cold Metal Forming (in German), Thesis, TH Hannover, 1962.

    Google Scholar 

  9. Lueg, W.; Krause, U.: Flow Stress of Steel C45 when Hot Upsetting with Intermediate Strain Rates (in German), Stahl und Eisen 80 (1960), pp. 1061–1067.

    Google Scholar 

  10. Bühler, H.; Vollmer, J.: Flow Curves of Metals at Large Strains and High Strain Rates (in German) Ind.-Anz. 91 (1969), pp. 2021–2023.

    Google Scholar 

  11. Siebel, E.; Schwaigerer, S.: Mechanics of Tensile Test (in German), Arch. Eisenhiittenwes. 19 (1948), pp. 145–152.

    Google Scholar 

  12. Lange, G.: Simplified Determination of Flow Curves of Metals in Tensile Tests During Necking of Specimen (in German), Arch. Eisenhiittenwes. 45 (1974), pp. 809–812.

    CAS  Google Scholar 

  13. Hensel, A.; Spittel, Th.: Force and Work Requirement of Metal Forming Processes (in German), Leipzig, Grundstoffindustrie, 1976.

    Google Scholar 

  14. Reihle, M.: A Simple Method of Determining Flow Curves of Steel at Room Temperature (in German), Arch. Eisenhiittenwes. 32 (1961), pp. 331–336.

    CAS  Google Scholar 

  15. Jöller, A. et al.: One Possibility of an Objective Uniform Elongation Determination (in German), Berg- u. Hüttenm.. Mh. 126 (1981), pp. 80–83.

    Google Scholar 

  16. El-Magd, E.: Determining Flow Curves in Tensile Tests (in German), Arch. Eisenhüttenwes. 45 (1974), pp. 83–89.

    CAS  Google Scholar 

  17. ASTM E 9–81: Standard Method of Compression Testing of Metallic Materials at Room Temperature, 1981.

    Google Scholar 

  18. Papirno, R.: Inelastic Buckling of ASTM Standard E 9 Compression Specimens, J. Testing Eval. 15 (1987), pp. 133–135.

    Article  Google Scholar 

  19. Stahl-Eisen-Prüfblatt 1123: Zylinderstauchversuch zur Ermittlung von Kaltfließkurven (Upsetting Test on Cylindrical Specimens for Determining Flow Curves at Low Temperatures), 2nd Ed., August 1986.

    Google Scholar 

  20. Lee, C.H.; Altan, T.: Influence of Flow Stress and Friction upon Metal Flow in Upset Forging of Ring and Cylinders, Trans. ASME, J. Eng. for Industry, 94 (1972), pp. 775–782.

    Article  Google Scholar 

  21. Siebel, E.; Pomp, A.: Determination of Flow Stress of Metals with the Upsetting Test (in German), Mitt. KW1 Eisenforsch. 9 (1927), pp. 157–171.

    Google Scholar 

  22. Avitzur, B.: Metal Forming, Processes and Analysis, New York, McGraw-Hill, 1967.

    Google Scholar 

  23. Banerjee, J.K.: Barrelling of Solid Cylinders under Axial Compression, Trans. ASME, J. Eng. Mater. Technol. 107 (1985), pp. 138–144.

    Article  Google Scholar 

  24. Samanta, S.K.: On the Limit of Plastic Deformation in Compression of Circular Cylinders, Int. J. Fracture 11 (1975), pp. 301–313.

    Article  CAS  Google Scholar 

  25. Diether, U.: Determining Flow Curves at Elevated Temperatures in the Upsetting Test (in German), Seminar “Neuere Entwicklungen in der Massivumformung”, Forschungsgesellschaft Umformtechnik mbH., Stuttgart, 26.–27.6.1979.

    Google Scholar 

  26. Pawelski, O.: Comparison of Methods for Testing the Hot Formability of Metals (in German), in: Warmumformung und Warmfestigkeit, Symp. Bad Nauheim 1975, Oberursel, DGM, 1976, pp. 1–24.

    Google Scholar 

  27. Panknin, W.; Bach, M.: Guide to Experimental Determination of Flow Curves of Metals (in German), DFBO-Mitt. (1972), pp. 15–22.

    Google Scholar 

  28. Nebe, G.; Stenger, H.: Recording of Flow Curves on Steel Specimens (in German), Materialprüf. 6 (1964), pp. 157–162.

    Google Scholar 

  29. Bramley, A.N.; Abowl, N.A.: Stress-Strain-Curves from the Ring Test, Proc. 15th MTDR Conf., London, 1975, pp. 431–436.

    Google Scholar 

  30. Sachs, G.: Z. Metallkde. 16 (1924), p. 55.

    Google Scholar 

  31. Sato, Y.; Takeyama, H.: An Extrapolation Method for Obtaining Stress-Strain-Curves at High Rates of Strain in Uniaxial Compression, Tech. Rep. Tohoku Univ. 44 (1980), pp. 287–302.

    Google Scholar 

  32. Wiegels, H.; Herbertz, R.: Upsetting Test on Cylindrical Test Pieces with High Friction for Determining Flow Stress (in German), Stahl und Eisen 99 (1979), pp. 1380–1390.

    Google Scholar 

  33. Schey, J.A. et al.: The Effect of Friction on Pressure in Upsetting at Low Diameter to Height Ratios, J. Mech. Work. Technol. 6 (1982), pp. 23–34.

    Article  Google Scholar 

  34. Osakada, H. et al.: A Method of Determining Flow Stress under Forming Conditions, Annals of the C1RP 30/1 (1981), pp. 135–138.

    Article  CAS  Google Scholar 

  35. Polakowski, N.H.: The Compression Test in Relation to Cold Rolling, J. Iron Steel Inst. 163 (1949), pp. 250–276.

    CAS  Google Scholar 

  36. Pöhlandt, K.: Contribution to the Recording of Flow Curves at High Natural Strain (in German), Seminar “Neuere Entwicklungen in der Massivumformung”, Forschungsgesellschaft Umformtechnik mbH., Stuttgart, 26. 27.6.1979.

    Google Scholar 

  37. Holzer, A.J.: Specimen Geometry and Friction in Dynamic Compression, Annals of the CIRP 29/1 (1980), pp. 135–139.

    Article  Google Scholar 

  38. Rastegaev, M.V.: New Method of Homogeneous Upsetting of Specimens for Determining the Flow Stress and the Coefficients of Inner Friction (in Russian), Zav. Lab. (1940), pp. 354.

    Google Scholar 

  39. Turno, A.: Determining Strain-Hardening Curves Using Specimens with End Recesses (in Polish), Obrobka Plastyczna Poznan 11 (1972), pp. 123–127.

    Google Scholar 

  40. Krokha, V.A.: Basic Principles for Strain-Hardening of Metals and Alloys when Cold Upsetting (in Russian), Kuz. Stamp. Proizv. 10 (1977), pp. 29–47.

    Google Scholar 

  41. Pöhlandt, K.: Upsetting Test for Determining Flow Curves According to Rastegaev (in German), Ind.-Anz. 101 (1979) 48,

    Google Scholar 

  42. Pöhlandt, K.: Upsetting Test for Determining Flow Curves According to Rastegaev (in German), Ind.-Anz. 101 (1979) pp. 28–29 (HGF 79/26).

    Google Scholar 

  43. Wiegels, H.; Herbertz, R.: Upsetting Tests — A Suitable Method for Determining Flow Curves? (in German), Stahl und Eisen 101 (1981), pp. 1487–1492.

    Google Scholar 

  44. Chang, T.; Shü, U.: The Stress-Strain Relation Ship of Metals under Homogeneous Compression, Scientia Sinica 10 (1961), pp. 377–385.

    Google Scholar 

  45. Suyarov, D.I. et al.: Determination of Flow Stress of Metals (in Russian), Zav. Lab. 21 (1955), pp. 97–99.

    Google Scholar 

  46. Gunasekera, J. S. et al.: The Effect of Specimen Size on Stress-Strain Behavior in Compression, Trans. ASME, J. Eng. Mater. Technol. 104 (1982), pp. 274–279.

    Article  Google Scholar 

  47. Latocha, J.; Rafalski, Z.: Determination of Strain-Hardening Exponents of MIE Copper and Ms63 Brass (in Polish), Rudy Metale 21 (1976), pp. 345–348.

    Google Scholar 

  48. Oberländer, T., Institut für Umformtechnik, Universität Stuttgart: Personal Communication 1988.

    Google Scholar 

  49. Rafalski, Z.; Misiolek, Z.: Evaluation of Plastic Properties of Cold Formed Metals (in German), Bänder Bleche Rohre 21 (1980), pp. 459–463.

    CAS  Google Scholar 

  50. Yerkovich, L.A.; Gurnieri, G.J.: Compression-Creep Properties of Several Metallic and Cermet Materials at High Temperatures, ASTM Proc. 55 (1955), pp. 732–754.

    CAS  Google Scholar 

  51. Pöhlandt, K.; Roll, K.: Upsetting Test for Determining Stress-Strain-Curves in the Range of Very High Strains, ASTM Symp. “Formability 2000 AD”, Chicago, 24.–25.6.1980, Philadelphia, PA, ASTM 1982, pp. 211–228.

    Google Scholar 

  52. Ford, H.: Researches into the Deformation of Metals by Cold Rolling, Proc. Inst. Mech. Eng. 159 (1948), pp. 115–143.

    Article  Google Scholar 

  53. Watts, A.B.; Ford, H.: On the Basic Yield Stress Curve for a Metal, Proc. Inst. Mech. Eng. 169 (1955), pp. 1141–1150.

    Article  CAS  Google Scholar 

  54. Green, A.P.: A Theoretical Investigation of the Compression of a Ductile Material Between Smooth Flat Dies, Phil. Mag. Ser. 7, 42 (1951), pp. 900–918.

    Google Scholar 

  55. Hill, R.: The Mathematical Theory of Plasticity, Oxford, Clarendon Press, 1950.

    Google Scholar 

  56. Lippmann, H.; Mahrenholtz, O.: Plasticity and the Forming of Metallic Materials (in German), Vol. 1, Berlin/Heidelberg/New York, Springer, 1967.

    Google Scholar 

  57. Pawelski, O. et al.: The Hot Forming Simulator of the Max-Planck-Institut für Eisenforschung — A New Concept for Studying Rapid Hot Forming Processes (in German), Stahl und Eisen 98 (1978), pp. 165–178.

    Google Scholar 

  58. Lonn, A.H.; Schey, J.A.: Development of the Plane-Strain Compression Test, Proc. NAMRCII, Madison, Wise, 20.–22.5–1974, pp. 165–178.

    Google Scholar 

  59. Thomason, P.-F. et al.:The Effect of Temperature and Strain Rate on the Yield Stress-Strain Relationship for Alloy Steels, Univ. of Salford, Dept. of Mech. Eng., Res. Rep. No. 69/33, Salford, GB, 1969.

    Google Scholar 

  60. Vollmer, J.: Measurement of Flow Stress of Metallic Materials Mainly for High Strains and High Strain Rates (in German), Thesis, TU Hannover, 1969.

    Google Scholar 

  61. Kaspar, R.; Pawelski, O.: A Computer Controlled Simulation of Hot Work by Flat Compression on a High Speed Servo-Hydraulic Testing Machine, Proc. 19th MTDR Conf., Manchester, GB, 13.–15.9.1978, pp. 247–253.

    Google Scholar 

  62. Bishop, J.F.W.: On the Effect of Friction on Compression and Indentation between Flat Dies, J. Mech. Phys. Solids 6 (1958), pp. 132–149.

    Article  Google Scholar 

  63. Kubie, J.; Delamare, F.: Measurement of the Compressive Yield Stress of a Material by Means of a Double Punch. Application to Sheet Steel (in French), Mem. Etudes Sci. Rev. Metall. 78 (1981), pp. 201–207.

    CAS  Google Scholar 

  64. DIN 1319: Grundbegriffe der Meßtechnik. Teil 3: Begriffe für die Meßunsicherheit und für die Beurteilung von Meßgeräten und Meßeinrichtungen (Basic Principles of Measuring Technique. Part 3. Definitions and Terms for Measuring Uncertainty and for Evaluating Measuring Devices and Tools), August 1983.

    Google Scholar 

  65. Reicherter, K.: Investigations on the Plastic Behavior of Cylindrical Specimens (in German), Thesis, TH Stuttgart, 1950.

    Google Scholar 

  66. Straßburger, C; Robiller, G.: Recording of Flow Curves of Non-alloyed Steels at the Cold Upsetting Test (in German), Stahl und Eisen 93 (1973), pp. 1164–1170.

    Google Scholar 

  67. Final Report of Research Project La 155/89 of DFG: “Use of New Specimens for Determining Flow Curves in Upsetting Tests” (in German), Inst, f. Umformtechnik, Univ. Stuttgart, 1981.

    Google Scholar 

  68. Wagener, H.-W.: Upsetting Properties of Reactive and High Melting Point Metals (in German), Thesis, TH Hannover, 1965.

    Google Scholar 

  69. Wiegels, H.; Herbertz, R.: Influence of Measuring Accuracy of Force and Distance on the Uncertainty when Determining Flow Curves in the Cylinder Upsetting Test (in German), Stahl und Eisen 100 (1980), pp. 1548–1552.

    Google Scholar 

  70. Saluja, S.S. et al.: A Simple Method for Flow Stress Determination under Metal Working Conditions, Proc. NAMRC-1X, University Park, PA, 19.–22.5.1981, pp. 153–157.

    Google Scholar 

  71. Rasmussen, S.N. et al.: Further Development of the Rastegaev Upsetting Test for Recording Flow Curves (in German), wt.-Z. ind. Fertig. 74 (1984), pp. 667–670.

    Google Scholar 

  72. Stahl-Eisen-Prüfblatt 1114: Verdrehversuch zur Ermittlung von Kennwerten für das Verhalten von Stählen bei der V/armumformung (Torsion Test for Evaluating the Hot Forming Behavior of Steels), in Preparation.

    Google Scholar 

  73. Bailey, J.A.: Fundamental Aspects of Torsional Loading, in: (Ed.) Newby, R.: Metals Handbook, Vol. 8: Mechanical Testing, 9th Ed., Metals Park, Ohio, ASM, 1985.

    Google Scholar 

  74. Pöhlandt, K.: Torque and Elongation during Fracture in Torsional Testing (in German), Materialprüf. 21 (1979), pp. 7–12.

    Google Scholar 

  75. Pöhlandt, K. et. al.: Torsion Test on Solid and Tubular Specimens for Testing the Plastic Behavior of Metals, Arch. Eisenhüttenwes. 55 (1984), pp. 149–158.

    Google Scholar 

  76. Stüwe, H.-P.; Turck, H.: On the Determination of Flow Curves in the Torsion Test (in German), Z. Metallkde. 55 (1964), pp. 699–703.

    Google Scholar 

  77. Pöhlandt, K.; Tekkaya, A.E.: Torsional Testing for Recording Flow Curves under the Consideration of Strain Rate (in German), Z. Metallkde. 76 (1985), pp. 108–114.

    Google Scholar 

  78. (Ed.) Verein Deutscher Eisenhüttenleute (VDEh): Fundamental Aspects of Plastic Deformation (in German), Düsseldorf, Stahleisen, 1966.

    Google Scholar 

  79. Pöhlandt, K.; Tekkaya, A.E.: Torsion Testing — Plastic Deformation to High Strains and High Strain Rates, Mater. Sci. Technol. 1 (1985), pp. 972–977.

    Article  Google Scholar 

  80. Pöhlandt, K.: Basic Tests for Recording Flow Curves of Metallic Materials for Bulk Forming (in German), Draht 36 (1985), pp. 320–324 and

    Google Scholar 

  81. Pöhlandt, K.: Basic Tests for Recording Flow Curves of Metallic Materials for Bulk Forming (in German), Draht 36 (1985), pp. 432–434.

    Google Scholar 

  82. Witzel, W.: Inhomogeneous Deformation Due to Changes of Texture (in German), Z. Metallkde. 69 (1978), pp. 337–343.

    CAS  Google Scholar 

  83. Day, W.A.: On the Reiner-Weissenberg Criterion for Yield, Q. J. Mech. Appl. Math. 28 (1975), pp. 207–221.

    Article  Google Scholar 

  84. Sellars, CM.; Tegart, W.J.: Relation between Strength and Structure During Hot Deformation (in French), Mem. Etudes Sc. Rev. Metall. 63 (1966), pp. 731–746.

    CAS  Google Scholar 

  85. (Ed.) Blumenauer, H.: Materials Testing (in German), Leipzig, Grundstoffindustrie, 1976.

    Google Scholar 

  86. Häßner, F.; Hemminger, W.: Stored Energy in Copper after Rolling and Torsion (in German), Z. Metallkde. 69 (1978), pp. 553–563.

    Google Scholar 

  87. Heil, H.P.; Lienhardt, A.: Determining Isothermal Flow Curves of Steels at Temperatures from 20°C to 200°C (in German), Arch. Eisenhüttenwes. 45 (1974), pp. 91–98.

    CAS  Google Scholar 

  88. Schack, J.: Behavior of Flow Stress of Iron-Manganese-Carbon Alloys in the Blue Brittleness Range (in German), Thesis, TH Hannover 1965.

    Google Scholar 

  89. Doraivelu, S.M.; Gopinathan, Y.: Determination of Flow Stress of 18–4-1 Alloy Steel Taking into Account the Change in Temperature During Dynamic Deformation, Trans. IIM 32 (1979), pp. 42–46.

    CAS  Google Scholar 

  90. Bauer, D.: The Influence of High Strain Rates on Cold Forming of Steel, Copper and Aluminum (in German), Fortschr.-Ber. der VDI-Z., Reihe 2, Nr. 26, Düsseldorf, VDI-Verlag, 1973.

    Google Scholar 

  91. Dressel, P.-G.: The High Temperature Tensile Test as Test Method for Determining Characteristic Values for Hot Forming of Steels (in German), in: (Ed.) Verein Deutscher Eisenhüttenleute (VDEh): Determining Characteristic Values for Hot Formability of Steels (in German), Düsseldorf, Stahleisen, 1972.

    Google Scholar 

  92. Ilschner, B.: High Temperature Plasticity (in German), Berlin/Heidelberg/New York, Springer, 1973.

    Google Scholar 

  93. ASTM E 209–65 (1981): Standard Practice for Compression Tests of Metallic Materials at Elevated Temperatures with Conventional or Rapid Heating Rates and Strain Rates, 1965 (reapproved 1981).

    Google Scholar 

  94. Hawkyard, J.B. et al.: A Wedge Plastometer for Hot Multistage Compression Testing, J. Mech. Work. Technol. 1 (1978), pp. 291–298.

    Article  Google Scholar 

  95. Hartley, CS.; Jenkins, D.A.: Tensile Testing at Constant True Plastic Strain Rate, J. Metals 32 (1980), pp. 23–29.

    Google Scholar 

  96. Immarigeon, J.-P.A. et al.: A Hot Compression Testing Apparatus for the Study of Isothermal Forging, J. Test. Eval. (JTEVA) 8 (1980), pp. 273–281.

    Article  Google Scholar 

  97. Wulf, G.: High Strain Rate Compression of Titanium and Some Titanium Alloys, Int. J. Mech. Sci. 21 (1979), pp. 713–718.

    Article  Google Scholar 

  98. Lahoti, G.D.; Altan, T.: Prediction of Temperature Distributions in Axysymmetric Compression and Torsion, Trans. ASME, J. Eng. Mater. Technol. 97 (1975), pp. 113–120.

    Article  Google Scholar 

  99. Metzler, H.-J.: The Influence of Tool Speed on the Upsetting Process (in German), Berichte aus dem Institut für Umformtechnik, Universität Stuttgart, No. 21, Essen, Girardet, 1970.

    Google Scholar 

  100. Kopp, R. et al.: Influence of Flow Stress Accuracy on the Results of Metall Forming Processes, steel research 59 (1988), pp. 25–30.

    CAS  Google Scholar 

  101. Bühler, H.-E.: The Hot Upsetting Test for Determining Characteristic Values for Hot Forming of Steels (in German), in: (Ed.) Verein Deutscher Eisenhüttenleute (VDEh): Determining Characteristic Values for Hot Formability of Steels (in German), Düsseldorf, Stahleisen, 1972.

    Google Scholar 

  102. Meyer-Nolkemper, H.: Flow Curves of Metallic Materials (in German), HFF-Ber. No. 4, Hannover, Hannoversches Inst. f. Fertigungsfragen, 1978.

    Google Scholar 

  103. Gräber, A.: Determination of Flow Curves in the Torsion Test (in German), in: Seminar “Neuere Entwicklungen in der Massivumformung”, Forschungsges. Umformtechnik mbH., Stuttgart, 2.–3. June 1987.

    Google Scholar 

  104. Horiuchi, M.R. et al.: The Characteristics of the Torsion Test for Assessing Hot Workability of Aluminum Alloys, Inst. Space Aeronautical Science, Univ. of Tokyo, Rep. No. 443, Tokyo 1970.

    Google Scholar 

  105. Sheppard, T.; Wright, D.S.: Determination of Flow Stress, Part 1: Constitutive Equations, Metals Technol. 6 (1979), pp. 215–223.

    CAS  Google Scholar 

  106. Wright, D.S.; Sheppard, T.: Determination of Flow Stress, Part 2: Radial and Axial Temperature Distribution During Torsion Testing, Metals Technol. 6 (1979), pp. 224–229.

    CAS  Google Scholar 

  107. Weber, H.-H.: The Hot Torsion Test and its Validity as Measure for Forming Behavior of Steels at Elevated Temperatures (in German), Thesis, B.A. Freiberg, 1968.

    Google Scholar 

  108. Hertel, J.: Investigations about Hot Formability of Steels Using the Torsion Test (in German), in: (Ed.) Verein Deutscher Eisenhüttenleute (VDEh): Determining Characteristic Values for Hot Formability of Steels (in German), Düsseldorf, Stahleisen, 1972.

    Google Scholar 

  109. Ryan, N.D. et al.: The Deformation Behavior of Types 304, 316 and 317 Austenitic Stainless Steels During Hot Torsion, Can. Metall. Quarterly 22 (1983), pp. 369–378.

    Google Scholar 

  110. Vanovsek, W.; Trenkler, H.: New Investigations on a Hot Torsion Testing Device (in German), Berg- und Hüttenm. Mh. 122 (1977), pp. 397–409.

    CAS  Google Scholar 

  111. Witzel, W.: Possibilities of Application of the Torsion Test when Investigating Metallic Materials (in German), Radex-Rdsch. (1980), pp. 151–160.

    Google Scholar 

  112. Blankenagel, H.-J.; Fischer, F.: Measuring of Flow Stress Behavior of Fe-Alloys and Brass at Very High Strain Rates (in German), Blech Rohre Profile 26 (1979), pp. 155–162.

    CAS  Google Scholar 

  113. Jahn, F.: A New Method of Determining Yield Stress of Metallic Materials at Highest Strain Rates (in German), Thesis, TH Karlsruhe, 1979.

    Google Scholar 

  114. Holzer, A.J.: A Tabular Summary of Some Experiments in Dynamic Plasticity, Trans. ASME, J. Eng. Mater. Technol. 101 (1979), pp. 231–235.

    Article  CAS  Google Scholar 

  115. Bauer, D.: Dynamic Expansion Test, a Measuring Method for Determining Flow Stress at High Strain Rates (in German), Ind.-Anz. 96 (1974), pp. 1886–1887 (HGF 74/54).

    Google Scholar 

  116. Nicholas, T.: Tensile Testing of Materials at High Rates of Strain, Exp. Mech. 21 (1981), pp. 177–185.

    Article  Google Scholar 

  117. Hashmi, M.S.J, et al.: High Strain Rate Properties of Material: Design and Development of a Testing Equipment and Methodology, Ind. J. Mach. Tool Des. Res. 25 (1985), pp. 39–50.

    Article  Google Scholar 

  118. Ogushi, A.; Yoshida, S.: A Magnetostrictive Load Cell for Use Under High Hydrostatic Pressure, Jap. J. Appl. Phys. 7 (1968), pp. 622–678.

    Google Scholar 

  119. Sismincev, V.F. et al.: Set-up for Materials Testing Under Hydrostatic Pressure (in Russian), Zav. Lab. 44 (1978), pp. 1279–1280.

    Google Scholar 

  120. Bogatov, A.A. et al.: An Investigation of the Plasticity of Metals Under Hydrostatic Pressure (in Russian), Fiz. Met. Metallov. 45 (1978), pp. 1089–1094.

    Google Scholar 

  121. (Ed.) Pugh, H.L.D.: Mechanical Behavior of Materials Under Pressure, Amsterdam, Elsevier, 1970.

    Google Scholar 

  122. Domke, W.: Materials Science and Materials Testing (in German), 5th Ed., Essen, Girardet, 1973.

    Google Scholar 

  123. Schmidt, W.; Schaffrath, W.: Exchangeability of Hardness and Strength Values and Influence of Tempering for Tempered and Cold Working Steels (in German), Materialprüf. 26 (1984), pp. 57–61.

    Google Scholar 

  124. Böklen, R.: On the Correlation Between Hardness Indentation and Flow Curves of Metallic Materials (in German), Materialprüf. 25 (1983), pp. 117–119.

    Google Scholar 

  125. Heubner, U.: Report “Superplasticity” (in German), Oberursel, DGM, 1978.

    Google Scholar 

  126. Höneß, H.: On the Plastic Behavior of Powder Metals at Room Temperature (in German), Berichte aus dem Institut für Umformtechnik, Universität Stuttgart, No. 40, Essen, Girardet, 1976.

    Google Scholar 

  127. ASTM B 331–85: Standard Test Method for Compressibility of Metal Powders in Uniaxial Compaction, 1985.

    Google Scholar 

  128. Huppmann, W.J.; Hirschvogel, M.: Powder Forging, Ind. Metall. R2v. 23 (1978), pp. 209–240.

    Article  CAS  Google Scholar 

  129. ISO 2740–1986: Sintered Metal Materials (Excluding Hardmetal) — Tensile Test Pieces, 1986.

    Google Scholar 

  130. Rao, K.P.; et al.: Flow Curves and Deformation of Materials at Different Temperatures and Strain Rates, J. Mech. Work. Technol. 6 (1982), pp. 63–88.

    Article  CAS  Google Scholar 

  131. Christ, R.W.; Swanson, S.R.: Alignment Problems in the Tensile Test, J. Test. Eval. (JTEVA) 4 (1976), pp. 405–417.

    Article  Google Scholar 

  132. Lange, F.F.; Diaz, E.S.: Powder-Cushion Gripping to Promote Good Alignement in Tensile Testing, J. Test. Eval. (JTEVA) 6 (1978), pp. 320–323.

    Article  Google Scholar 

  133. Pink, E.: Standardizing the Tensile Test from the Viewpoint of Metals Physics (in German), Berg- und Hüttenm. Mh. 125 (1980), pp. 107–112.

    CAS  Google Scholar 

  134. Bauer, F. et al.: On the Analysis of Repeatability of Characteristic Values in the Controlled Tensile Test (in German), Berg- und Hüttenm. Mh. 125 (1980), pp. 113–116.

    CAS  Google Scholar 

  135. Kurzmann, W.; Heimbrodt, P.: Influence of the Load Conditions on the Results of the Tensile Test (in German), Neue Hütte 24 (1979), pp. 426–430.

    CAS  Google Scholar 

  136. Baptista, A.A.; Forts, M.A.: Computer Simulation of the Tensile Test, J. Test. Eval. (JTEVA) 7 (1979), pp. 254–263.

    Article  Google Scholar 

  137. Späth, W.: Shape Deviations of a Specimen in the Tensile Test (in German), Metall 30 (1976), pp. 752–754.

    Google Scholar 

  138. Andresen, K.; Lange, G.: Comparison between Measured and Calculated Necking Contours of Tensile Specimens (in German), Arch. Eisenhüttenwes. 48 (1977), pp. 409–413.

    CAS  Google Scholar 

  139. Dahl, W.; Rees, H.: Course of the Contour Line of the Specimen Surface in the Necking Region in the Tensile Test (in German), Materialprüf. 19 (1977), pp. 304–310.

    CAS  Google Scholar 

  140. El-Magd, E.; Troost, A.: Instability in the Tensile Test (in German), Arch. Eisenhüttenwes. 48 (1977), pp. 43–46.

    Google Scholar 

  141. Christodoulou, N.; Jonas, J.J.: Effect of Work Hardening Flow Law and Sample Geometry on the Forming Limit on Inuniaxial Tension, Can. Metall. Quarterly 22 (1983), pp. 379–384.

    Google Scholar 

  142. Melander, A.: Necking in Cylindrical Tensile Specimens, Scand. J. Metall. 9 (1980), pp. 51–57.

    CAS  Google Scholar 

  143. Thomsen, E.G.: A Direct Method for Obtaining an Effective Stress-Strain-Curve from a Tension Test, Proc. NAMRC-V, Amherst/Mass., 25–27.5.1977, pp. 139–146.

    Google Scholar 

  144. Thomsen, E.G.: Stresses in Torsion Test Bars after Multi-Pass Drawing of ETPC Copper, in: (Ed.) Lange, K.: Advanced Technology of Plasticity, 1987, Vol. 1, Proc. 2nd 1CTP, Stuttgart, 24.–28.8.1987, Springer, 1987, pp. 393–398.

    Google Scholar 

  145. Lange, G.: The Influence of a Testing Machine Stiffness on the Result of Tensile Tests (in German), Arch. Eisenhüttenwes. 43 (1972), pp. 67–75.

    CAS  Google Scholar 

  146. Kravcenko, V.: Tensile Test on Steel from the Viewpoint of Standardization (in German), Berg und Hüttenm. Mh. 122 (1977), pp. 255–263.

    CAS  Google Scholar 

  147. Martin, J.J.: Tension Testing Machines and Extensometers, in: (Ed.) Newby, R.: Metals Handbook, Vol. 8: Mechanical Testing, 9th Ed., Metals Park, Ohio, ASM, 1985.

    Google Scholar 

  148. Jacoby, G.; Mall, G.: Problems in Tensile Tests and the Development of Tensile Testing Machines (in German), Berg- und Hüttenm. Mh. 122 (1977), pp. 264–274.

    Google Scholar 

  149. Zillmann, J.: Practical Experience in Materials Testing (in German), Materialprüf. 25 (1983), pp. 351–367.

    Google Scholar 

Further Reading

  1. Barrett, CS.; Massalski, T.B.: Structure of Metals, 3rd Ed., New York, McGraw-Hill, 1966.

    Google Scholar 

  2. McLean, D.: Mechanical Properties of Metals, Huntington, N.Y., Robert E. Krieger Publ. Comp., 1977.

    Google Scholar 

  3. Chait, R.; Papirno, R.: Compression Testing of Homogeneous Materials and Composites, Symposium, Williamsburg, VA, 10.–11.3.1982, Philadelphia, ASTM, 1983.

    Book  Google Scholar 

  4. ASTM E 4–83a: Standard Practices for Load Verification of Testing Machines, 1983.

    Google Scholar 

  5. ASTM B 312–82: Standard Test Method for Green Strength for Compacted Metal Powder Specimens, 1982.

    Google Scholar 

  6. ASTM B 528–83a: Standard Test Method for Transverse Rupture Strength of Sintered Metal Powder Specimens, 1983.

    Google Scholar 

  7. ISO 4492–1985: Metallic Powders, Excluding Powders for Hardmetals — Determination of Dimensional Changes Associated with Compacting and Sintering, 1985.

    Google Scholar 

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Pöhlandt, K. (1989). Determination of Flow Curves for Bulk Metal Forming. In: Materials Testing for the Metal Forming Industry. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-50241-5_2

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