关键词: 粉末高温合金, 粘塑性, 本构模型

Abstract:

This paper performed straining rate controlled uniaxial tension tests of FGH95 powder metallurgy superalloy at 550℃, 600℃ and 650℃. The cyclic loading test at 550℃ was also made. The results show that when the test temperature is less than 600℃ the stress strain curves display an ascending trend without stress saturation and the thermal recovery is not remarkable. At 650℃, there is obvious stress saturation under slow straining rates, and the creep effect must be considered. FGH95 is a kind of cyclic hardening material, which is slightly sensitive to the straining rate. Finally, the Bonder Partom constitutive model parameters are evaluated on the basis of the above test curves. The theoretical results are accordant to the experiment. The Bonder Partom constitutive model can simulate the stress strain curve, the straining rate and cyclic hardening characteristics of FGH95. The paper provides a base for the stress analysis of powder metallurgy superalloy components under high temperature.

Key words: powder metallurgy superalloy, visco-plasticity, constitutive model