Plastic deformation of polycrystals. Report II. Limit of elasticity and strain hardening of molybdenum, niobium, and iron

Autor: V. F. Moiseev, É. P. Pechkovskii, V. A. Rafalovskii, O. I. Ban'kovskii
Rok vydání: 1989
Předmět:
Zdroj: Strength of Materials. 21:338-344
ISSN: 1573-9325
0039-2316
DOI: 10.1007/bf01529185
Popis: 1. It is shown that the most reliable values of the parameters σ0 and Ky in the equation of grain boundary strengthening can be obtained from the dependency of the true limit of elasticity σe on the grain size D−1/2. 2. The concept of the normalized coefficient Ky/σ0 is introduced, which allows one in the first instance to illustrate the general nature of grain boundary strengthening in metals with various types of crystallographic lattices, and in the second, to evaluate the contributions to grain boundary strengthening due to grain orientation in polycrystalline materials and segregation effects. 3. In accordance with the proposed scheme of strain hardening in polycrystalline bcc metals, once a dislocation cell structure forms, all grain sizes experience similar hardening effects. At this stage, the effect of the grain size on the level of the flow stress is due to the contribution of grain boundary strengthening to the size of the true limit of elasticity.
Databáze: OpenAIRE
Externí odkaz: