On tension-torsion testing of solid cylindrical specimens

Received: 18 April 2018; Revised: 05 July 2018; Accepted: 23 July 2018
This paper is written in Russian
Citation: R.M. Kashaev. On tension-torsion testing of solid cylindrical specimens. Letters on Materials, 2018, 8(3) 346-352
BibTex   DOI: 10.22226/2410-3535-2018-3-346-352

Abstract

The function of the force parameters (axial force and torque) recorded in the experiment and the preset kinematic parameters (the rate of tension and the torsional velocity), the strain rate sensitivity coefficient and the approach angle between the stress vectors and the strain rate on the specimen surface under complex loading.One of the features of the rheological behavior of metals and alloys at high temperature is their sensitivity to the rate of deformation. This paper proposes a method for studying the dependence between stresses and strain rates based on experimental data for solid cylinder specimen deformed in tension with torsion under non-proportional deformation (complex loading). A strain trajectories with two straight lines is considered. The deformation process is described by two components of the strain rate tensor (axial and shear) in the form of functions of time. At each time, we record the axial force and torque corresponding to them. The function of the force parameters (axial force and torque) recorded in the experiment and the preset kinematic parameters (the rate of tension and the torsional velocity), the strain rate sensitivity coefficient, the strain hardening exponent and the approach angle between the stress vectors and the strain rate on the specimen surface under non-proportional deformation is obtained. The paper also considers particular cases of deformation trajectories of the double-link type, when the second link is uniaxial tension, pure torsion or tension combined with torsion. Analytic formulas for calculating the stress vector and its components, and the approach angle that characterizes the direction of the stress vector in relation to the strain rate vector for points on the specimen cylindrical surface are derived. The method proposed is a generalization of the experimental procedure for plotting shear diagrams from the torsion test data for a material sensitive to the rate and level of strains, based on the Fields Backofen equation. The proposed method was used in processing experimental data obtained after testing the Ti-6Al-4V titanium alloy under non-proportional deformation in tension with torsion under conditions of superplasticity. When processing the test data, the compliance of the “specimen – testing machine” system was taken into account.

References (20)

1.
A. A. Ilyushin. Plasticity. Fundamentals of general mathematical theory. Moscow, The USSR AS (1963) 272 p. (in Russian) [А. А. Ильюшин. Пластичность. Основы общей математической теории. Москва, АН СССР (1963) 272 с.]
2.
V. G. Zubchaninov. Foundations of theory of elasticity and plasticity. Moscow, High School (1999) 368 p. (in Russian) [В. Г. Зубчанинов. Основы теории упругости и пластичности. Москва, Высш. Школа (1999) 368 с.]
3.
V. S. Bondar, V. V. Danshin. Plasticity. Proportional and non-proportional loading. Moscow, FIZMATLIT (2008) 176 p. (in Russian) [В. С. Бондарь, В. В. Даншин. Пластичность. Пропорциональные и непропорциональные нагружения. Москва, ФИЗМАТЛИТ (2008) 176 с.]
4.
B. D. Annin, V. M. Jigalkin. Behavior of materials under conditions of complex loading. Novosibirsk, SO RAS (1999) 342 p. (in Russian) [Б. Д. Аннин, В. М. Жигалкин. Поведение материалов в условиях сложного нагружения. Новосибирск, СО РАН (1999) 342 с.]
5.
R. A. Vasin. In: Plastichnost i razrushenie tverdyih tel. Moscow, Nauka (1988) Ob eksperimental'nom issledovanii… P. 40 – 57. (in Russian) [Р. А. Васин. В кн.: Пластичн. и разрушение тверд. тел. Москва, Наука (1988). Об экспериментальном исследовании функционалов пластичности в теории упругопла-стических процессов. С. 40 – 57.]
6.
R. A. Vasin, A. N. Nikitochkin, P. M. Ogibalov. Mechanics of Polymers. 4, 739 (1973). (in Russian) [Р. А. Васин, А. Н. Никифоров, П. М. Огибалов. Механика полимеров. 4, 739 (1973).]
7.
R. A. Vasin, A. N. Nikitochkin, P. M. Ogibalov. Mechanics of Polymers. 2, 224 (1975). (in Russian) [Р. А. Васин, А. Н. Никифоров, П. М. Огибалов. Механика полимеров. 2, 224 (1975).]
8.
A. V. Muravlev. In: Proceedings of VIII International scientific workshop "Problemy prochnosti, plastichnosti i ustoichivosti v mehanike deformiruemogo tverdogo tela". Tver (2015) P. 25. (in Russian) [А. В. Муравлёв. Материалы VIII Международного научного симпозиума "Проблемы прочности, пластичности и устойчивости в механике деформируемого твердого тела". Тверь (2015) С. 25.]
9.
K. Zhang, M. K. Khraisheh, A. E. Bayoumi, C. H. Hamilton, H. M. Zbib. Proceeding ICSAM-94. (1994) P. 583 – 588.
10.
Y. Ohashi, M. Tokuda. J. Mech. Phys. Solids 21, 241 (1973).
11.
M. Tokuda, Y. Inagaki, H. Yoshida. JSME International Journal. A. 37(2), 117 (1993).
12.
V. G. Zubchaninov, N. L. Ohlopkov. Strench of Materials. 4, 19 (1996). (in Russian) [В. Г. Зубчанинов, Н. Л. Охлопков. Проблемы прочности. 4, 19 (1996).]
13.
V. G. Zubchaninov, V. I. Gultiaev, A. A. Alekseev, V. V. Garanikov, S. L. Subbotin. Mater. Phys. and Mech. 32, 305 (2017).
14.
R. A. Vasin, A. А. Ilyushin, P. A. Mossakovski. Solid Mechanics. 2, 177 (1994). (in Russian) [Р. А. Васин, А. А. Ильюшин, П. А. Моссаковский. Механика твердого тела. 2, 177 (1994).]
15.
A. V. Muravlev. In: Vestnik MGU, ser. Mat. Mech. 5, 74 (1996). (in Russian) [А. В. Муравлев. Вест. МГУ, сер. Мат. Мех. 5, 74 (1996).]
16.
H. J. McQueen, W. Blum and Q. Zhu. Superplasticity in Advanced Materials, ICSAM-94, Moscow, T. G. Langdon (ed.), Trans. Tech. Pub., Zurich, Switzerland, 1994, P. 193 – 200.
17.
F. U. Enikeev. Metals. 4, 66 (1999). (in Russian) [Ф. У. Еникеев. Металлы. 4, 66 (1999).]
18.
R. A. Vasin, V. K. Berdin, R. M. Kashaev. Strength of Materials. 6, 509 (2001). [Р. А. Васин, В. К. Бердин, Р. М. Кашаев. Проблемы прочности. 6, 5 (2001).]
19.
V. K. Berdin, R. M. Kashaev. Strength of Materials. 1, 15 (2001). [В. К. Бердин, Р. М. Кашаев. Проблемы прочности. 1, 28 (2001).]
20.
R. A. Vasin, F. U. Enikeev. Introduction to superplasticity mechanics. Part 1. Ufa, Gilem (1998) 280 p. (in Russian) [Р. А. Васин, Ф. У. Еникеев. Введение в механику сверхпластичности. Ч. 1. Уфа, Гилем (1998) 280 с.]