依据热流变曲线研究材料在热形变过程中显微组织的变化

金属材料在热形变过程中可能会发生动态回复、动态再结晶、动态沉淀、静态回复、静态再结晶、静态沉淀、亚动态再结晶和应变诱导沉淀等显微组织的变化。本文综述了一种依据热流变曲线测定这些组织变化的试验方法。该方法不但能测定各种回复、再结晶和沉淀过程的动力学,而且能揭示它们之间的交互作用。由于该方法能直接对热形变高温状态进行测定,因而消除了淬火后通常在室温下间接测定所带来的试验误差。

A NEW METHOD BASED ON ANALYSIS OF FLOW CURVES FOR APPROACHING TO MICROSTRUCTURE CHANGES DURING HOT DEFORMATION

The mierostructure changes in metallic materials during hot deforma- tion may involve dynamic recovery, dynamic recrystallization, dynamic precipitation, static recovery, static recrystallization, static precipitation, post-dynamic recrystallization and strain-induced precipitation. A new mechanical method is described here to examine these microstructure changes. The technique is based on the flow curves obtained by hot tension, hot compression or hot torsion tests. It permits the determination of not only the kinetics of recovery, recrystallization and precipitation but also their interactions. Furthermore, as the test is carried out directly at high temperatures, it can eliminate the experimental errors resulted from quen- ching in conventional tests which are usually carried out at room tempera- ture.