Skip to main content Accessibility help
×
Home
  • Print publication year: 2021
  • Online publication date: May 2021

5 - Tensile Testing

Summary

The uniaxial tensile test is the most commonly used mechanical testing procedure, and indeed it is in very widespread use. However, while it is simple in principle, there are several practical challenges, as well as a number of points to be noted when examining outcomes. For example, there is the issue of converting between nominal (“engineering”) and true values of the stress and strain. While many stress–strain curves are presented, and often interpreted, only as nominal data, it is the true relationship that accurately reflects the mechanical response of the sample. Furthermore, conversion between nominal and true values is straightforward only while the stress and strain fields within the gauge length of the sample are uniform. This uniformity is lost as soon as the sample starts to deform in an inhomogeneous way within the gauge length, which most commonly takes the form of “necking.” After the onset of necking, which may be quite difficult to detect and could occur at an early stage, useful interpretation of the stress–strain curve becomes difficult. However, FEM modeling does allow various insights into the behavior in this regime, with potential for revealing information (about the fracture event) that is otherwise inaccessible. There are also several important points relating to the way that the strain is measured during a test.

Related content

Powered by UNSILO
1.Kuhn, H and Medlin, D, ASM Handbook Vol. 8: Mechanical Testing and Evaluation. Materials Park, OH: ASM International, 2000.
2.Davis, JR, Tensile Testing. Materials Park, OH: ASM International, 2004.
3.Von Goler, F and Sachs, G, Tensile tests on crystals of copper and alpha-brass. Zeitschrift Fur Physik, 1929. 55(9–10): 581620.
4.Osswald, E, Tensile tests on copper, nickel crystals. Zeitschrift Fur Physik, 1933. 83(1–2): 5578.
5.Hart, EW, Theory of tensile test. Acta Metallurgica, 1967. 15(2): 351355.
6.Nahak, B and Gupta, A, A review on optimization of machining performances and recent developments in electro discharge machining. Manufacturing Review, 2019. 6.
7.Nagimova, A and Perveen, A, A review on laser machining of hard to cut materials. Materials Today: Proceedings, 2019. 18: 24402447.
8.Kartal, F, A review of the current state of abrasive water-jet turning machining method. International Journal of Advanced Manufacturing Technology, 2017. 88(1–4): 495505.
9.Simons, G, Weippert, C, Dual, J and Villain, J, Size effects in tensile testing of thin cold rolled and annealed Cu foils. Materials Science and Engineering A: Structural Materials Properties Microstructure and Processing, 2006. 416(1–2): 290299.
10.Zhao, YH, Guo, YZ, Wei, Q, Topping, TD, Dangelewicz, AM, Zhu, YT, Langdon, TG and Lavernia, EJ, Influence of specimen dimensions and strain measurement methods on tensile stress–strain curves. Materials Science and Engineering A: Structural Materials Properties Microstructure and Processing, 2009. 525(1–2): 6877.
11.Yang, L and Lu, L, The influence of sample thickness on the tensile properties of pure Cu with different grain sizes. Scripta Materialia, 2013. 69(3): 242245.
12.Load Cell and Weigh Module Handbook, 2020. Available from: www.ricelake.com/lcwm.
13.Boyle, HB, Transducer Handbook. Oxford: Butterworth-Heinemann, 1992.
14.Bastias, PC, Kulkarni, SM, Kim, KY and Gargas, J, Noncontacting strain measurements during tensile tests. Experimental Mechanics, 1996. 36(1): 7883.
15.Anwander, M, Zagar, BG, Weiss, B and Weiss, H, Noncontacting strain measurements at high temperatures by the digital laser speckle technique. Experimental Mechanics, 2000. 40(1): 98105.
16.Pan, B and Tian, L, Advanced video extensometer for non-contact, real-time, high-accuracy strain measurement. Optics Express, 2016. 24(17): 1908219093.
17.McKinley, GH and Hassager, O, The Considere condition and rapid stretching of linear and branched polymer melts. Journal of Rheology, 1999. 43(5): 11951212.
18.Crist, B and Metaxas, C, Neck propagation in polyethylene. Journal of Polymer Science Part B: Polymer Physics, 2004. 42(11): 20812091.
19.Petrie, CJS, Considere reconsidered: necking of polymeric liquids. Chemical Engineering Science, 2009. 64(22): 46934700.
20.Matic, P, Kirby, GC and Jolles, MI, The relation of tensile specimen size and geometry effects to unique constitutive parameters for ductile materials. Proceedings of the Royal Society of London Series A: Mathematical and Physical Sciences, 1988. 417(1853): 309333.
21.Havner, KS, On the onset of necking in the tensile test. International Journal of Plasticity, 2004. 20(4–5): 965978.
22.Kim, HS, Kim, SH and Ryu, WS, Finite element analysis of the onset of necking and the post-necking behaviour during uniaxial tensile testing. Materials Transactions, 2005. 46(10): 21592163.
23.Joun, M, Choi, I, Eom, J and Lee, M, Finite element analysis of tensile testing with emphasis on necking. Computational Materials Science, 2007. 41(1): 6369.
24.Choung, JM and Cho, SR, Study on true stress correction from tensile tests. Journal of Mechanical Science and Technology, 2008. 22(6): 10391051.
25.Osovski, S, Rittel, D, Rodriguez-Martinez, JA and Zaera, R, Dynamic tensile necking: influence of specimen geometry and boundary conditions. Mechanics of Materials, 2013. 62: 113.
26.Ho, HC, Chung, KF, Liu, X, Xiao, M and Nethercot, DA, Modelling tensile tests on high strength S690 steel materials undergoing large deformations. Engineering Structures, 2019. 192: 305322.
27.Samuel, EI, Choudhary, BK and Rao, KBS, Inter-relation between true stress at the onset of necking and true uniform strain in steels – a manifestation of onset to plastic instability. Materials Science and Engineering A: Structural Materials Properties Microstructure and Processing, 2008. 480(1–2): 506509.
28.Guan, ZP, Quantitative analysis on the onset of necking in rate-dependent tension. Materials & Design, 2014. 56: 209218.
29.Campbell, JE, Thompson, RP, Dean, J and Clyne, TW, Comparison between stress–strain plots obtained from indentation plastometry, based on residual indent profiles, and from uniaxial testing. Acta Materialia, 2019. 168: 8799.
30.Cottrell, AH and Bilby, BA, Dislocation theory of yielding and strain ageing of iron. Proceedings of the Physical Society of London Section A, 1949. 62(349): 4962.
31.Brindley, BJ, Honeycombe, RW and Corderoy, DJ, Yield points and Luders bands in single crystals of copper-base alloys. Acta Metallurgica, 1962. 10(Nov): 10431050.
32.Neuhauser, H and Hampel, A, Observation of Luders bands in single crystals. Scripta Metallurgica et Materialia, 1993. 29(9): 11511157.
33.Lloyd, DJ and Morris, LR, Luders band deformation in a fine-grained aluminium alloy. Acta Metallurgica, 1977. 25(8): 857861.
34.Balasubramanian, N, Li, JCM and Gensamer, M, Plastic deformation and Luders band propagation in alpha brass. Materials Science and Engineering, 1974. 14(1): 3745.
35.Kyriakides, S and Miller, JE, On the propagation of Luders bands in steel strips. Journal of Applied Mechanics: Transactions of the ASME, 2000. 67(4): 645654.
36.Gorbatenko, VV, Danilov, VI and Zuev, LB, Plastic flow instability: Chernov–Luders bands and the Portevin–Le Chatelier effect. Technical Physics, 2017. 62(3): 395400.
37.Khotinov, VA, Polukhina, ON, Vichuzhan, DI, Schapov, GV and Farber, VM, Study of Luders deformation in ultrafine low-carbon steel by the digital image correlation technique. Letters on Materials, 2019. 9(3): 328333.
38.Zuev, LB, Gorbatenko, VV and Danilov, VI, Chernov–Luders bands and the Portevin–Le Chatelier effect as plastic flow instabilities. Russian Metallurgy, 2017(4): 231236.
39.Wang, XG, Wang, L and Huang, MX, In-situ evaluation of Luders band associated with martensitic transformation in a medium Mn transformation-induced plasticity steel. Materials Science and Engineering A: Structural Materials Properties Microstructure and Processing, 2016. 674: 5963.
40.Jafarian, H, Characteristics of nano/ultrafine-grained austenitic trip steel fabricated by accumulative roll bonding and subsequent annealing. Materials Characterization, 2016. 114: 8896.
41.Cai, MH, Zhu, WJ, Stanford, N, Pan, LB, Chao, Q and Hodgson, PD, Dependence of deformation behavior on grain size and strain rate in an ultrahigh strength-ductile Mn-based trip alloy. Materials Science and Engineering A: Structural Materials Properties Microstructure and Processing, 2016. 653: 3542.
42.Louche, H and Chrysochoos, A, Thermal and dissipative effects accompanying Luders band propagation. Materials Science and Engineering A: Structural Materials Properties Microstructure and Processing, 2001. 307(1–2): 1522.
43.Murav’ev, TV and Zuev, LB, Acoustic emission during the development of a Luders band in a low-carbon steel. Technical Physics, 2008. 53(8): 10941098.
44.Hauser, JJ and Jackson, KA, Effect of grip constraints on the tensile deformation of FCC single crystals. Acta Metallurgica, 1961. 9(1): 113.
45.Kim, JY and Greer, JR, Tensile and compressive behavior of gold and molybdenum single crystals at the nano-scale. Acta Materialia, 2009. 57(17): 52455253.
46.Sowerby, R and Johnson, W, Review of texture and anisotropy in relation to metal forming. Materials Science and Engineering, 1975. 20(2): 101111.
47.Kalidindi, SR, Modeling anisotropic strain hardening and deformation textures in low stacking fault energy FCC metals. International Journal of Plasticity, 2001. 17(6): 837860.
48.Dawson, PR, MacEwen, SR and Wu, PD, Advances in sheet metal forming analyses: dealing with mechanical anisotropy from crystallographic texture. International Materials Reviews, 2003. 48(2): 86122.
49.Wenk, HR and Van Houtte, P, Texture and anisotropy. Reports on Progress in Physics, 2004. 67(8): 13671428.
50.Tucker, GEG, Texture and earing in deep drawing of aluminium. Acta Metallurgica, 1961. 9(4): 275286.
51.Zhao, Z, Mao, W, Roters, F and Raabe, D, A texture optimization study for minimum earing in aluminium by use of a texture component crystal plasticity finite element method. Acta Materialia, 2004. 52(4): 10031012.
52.Raabe, D, Wang, Y and Roters, F, Crystal plasticity simulation study on the influence of texture on earing in steel. Computational Materials Science, 2005. 34(3): 221234.
53.Tiernan, P and Hannon, A, Design optimisation of biaxial tensile test specimen using finite element analysis. International Journal of Material Forming, 2014. 7(1): 117123.
54.Xiao, R, A review of cruciform biaxial tensile testing of sheet metals. Experimental Techniques, 2019. 43(5): 501520.
55.Teaca, M, Charpentier, I, Martiny, M and Ferron, G, Identification of sheet metal plastic anisotropy using heterogeneous biaxial tensile tests. International Journal of Mechanical Sciences, 2010. 52(4): 572580.
56.Nicholas, T, Tensile testing of materials at high rates of strain. Experimental Mechanics, 1981. 21(5): 177185.
57.Ellwood, S, Griffiths, LJ and Parry, DJ, A tensile technique for materials testing at high strain rates. Journal of Physics E: Scientific Instruments, 1982. 15(11): 11691172.
58.Smerd, R, Winkler, S, Salisbury, C, Worswick, M, Lloyd, D and Finn, M, High strain rate tensile testing of automotive aluminum alloy sheet. International Journal of Impact Engineering, 2005. 32(1–4): 541560.
59.Korhonen, AS and Kleemola, HJ, Effects of strain rate and deformation heating in tensile testing. Metallurgical Transactions A: Physical Metallurgy and Materials Science, 1978. 9(7): 979986.