Torsion Strength Measurement of Engineering Ceramics


Article Preview

This paper discusses the relationship between torsion strength and bending strength of Al2O3 and Si3N4 ceramics. Measurement of the torsion strength was carried out by a simplified torsion test method proposed by Yasuda and Tsutsumi. In this experiment, the average torsion strength was approximately 2/3 of its average bending strength for both ceramics. By estimating the characteristic strength σ0 in Weibull distribution from the strength data, σ0 in torsion is almost the same as that in bending, which agrees to the basic discussion in mechanics of materials. The characteristic strength σ0 is one of the normalized strength by eliminating the effects of specimen shape, dimensions and also its stress distribution, and therefore the apparent difference between torsion and bending strengths can be explained by the difference in effective surface area (Conversely, the measured torsion strength data by the simplified method must be reasonable). It reveals that biaxial fracture in tension/compression during torsion test is equivalent to uniaxial tensile fracture by this experiment.



Edited by:

Junichi Hojo, Tohru Sekino, Jian Feng Yang, Hyung Sun Kim and Wen Bin Cao




F. J. Feng and K. Yasuda, "Torsion Strength Measurement of Engineering Ceramics", Materials Science Forum, Vol. 922, pp. 110-115, 2018

Online since:

May 2018




* - Corresponding Author

[1] Lin HT, Ferber MK, Becher PF, Price JR, van Roode M, Kimmel JB, et al. Characterization of first-stage silicon nitride components after exposure to an industrial gas turbine. ‎J. Am. Ceram. Soc. 89 (2006) 258–265.


[2] Motoyashiki Y, Hasegawa S, Okudaira K, Sato E. Micrometeoroid impact on ceramic thin components for interplanetary probe. Int. J. Impact. Eng. 35 (2008) 1666–1671.


[3] Evans AG. A general approach for the statistical analysis of multiaxial fracture. ‎J. Am. Ceram. Soc. 61 (1978) 302–308.

[4] Broutman LJ, Krishnakumar SM, Mallick PK. Effects of combined stresses on fracture of alumina and graphite. ‎J. Am. Ceram. Soc. 53 (1970) 649–654.

[5] K.Yasuda, and S.Tsutsumi, Easy-to-use Torsion Test Method for Bioceramics,, Abstract Book of 40th International Conference and Exposition on Advanced Ceramics and Composites, Vol. 40, No. S5-037, p.184, (2016).

[6] K.Yasuda, and S.Tsutsumi, Challenges in Development of Easy-to-use Torsion Test Method for Bioceramics : Toward ISO Standard Proposal,, Abstract Book of 41th International Conference and Exposition on Advanced Ceramics and Composites, Vol. 41, No. ICACC-PACRIM-043-2017, p.51, (2017).


[7] S.P. Timoshenko and J.N. Goodier, The Theory of Elasticity, Chapter 11, Torsion, p.264, MacGrow-Hill Book Company, (1951).

[8] JIS R1601 Fine ceramics - Test method for flexural strengt at room temperature.

[9] J.M. Gere and S.P. Timoshenko, Mechanics of Materials, 3rd edition, Chapter 3, Torsion, p.173, PWS Publishing Company, (1990).

[10] ISO standard 20501 Fine ceramics – Weibull statistic for strength data.