Application of von Mises criterion to single and dual phase TiAl

Journal Article · Tue May 05 04:00:00 EDT 1998 · Scripta Materialia

DOI:https://doi.org/10.1016/S1359-6462(98)00082-7· OSTI ID:619516

Goo, E ^[1]

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1. Univ. of Southern California, Los Angeles, CA (United States). Dept. of Materials Science and Engineering

The von Mises criterion is a necessary condition for ductility in polycrystalline solids. Methods for determining whether a set of slip system satisfies the von Mises criterion are well established and presented in many textbooks. Determining if a set of twinning systems satisfies the von Mises criterion is complicated by the fact that twinning is unidirectional as opposed to slip which is bidirectional. Twinning occurs when the shear occurs in one direction and reversing the direction of the shear will not produce a twin and therefore twinning is unidirectional. A method has been devised for determining if a set of twin systems satisfies the von Mises criterion. This method is actually a more general method that is also applicable to slip as well as twinning because it makes no assumption of bidirectionality. In this paper it is shown what slip and twin systems observed in TiAl and Ti{sub 3}Al are needed to satisfy the von Mises criterion. It is also shown that the von Mises criterion may be applied to a two-phase alloy where there exist an orientation relationship, the von Mises criterion is satisfied.

• OSTI ID: 619516
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 11 Vol. 38; ISSN 1359-6462; ISSN SCMAF7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
DISLOCATIONS
DUCTILITY
SLIP
TITANIUM ALLOYS
TWINNING