一种奥氏体钢的应变硬化特性与界面强化

CHARACTERISTIC OF STRAIN HARDENING AND GRAIN BOUNDARY STRENGTHENING OF AN AUSTENITIC STEEL

本文对Fe-Ni-Mn-Cr奥氏体钢的应力—应变行为进行了分析。结果表明,应变硬化指数n随晶粒直径d的增加呈现出先增后降的趋势。当晶粒直径较大时,容易产生形变孪晶,并且在较小应变条件下,孪晶界可以阻止位错运动,进而产生一附加强化增量,这一强化增量随应变量的增加而减小。

The behaviour of stress-strain in a Fe-Ni-Mn-Cr austenitic steel has been investigated. It is showg that with the increase of grain diameter the sirain hardening exponent ni ncreases as the grain diameter is small and decreases as the diameter is large. It is easy to produce deformation twins in the state of large grain diameter. And under the condition of small strain, an additional strength increment will be introduced because the inter face of deformation twin obstructs the movement of dislocations. This strength increment, however, can be vanished when the steain becomes large.