铝单晶体潜在硬化的指向性行为研究  

A STUDY ON THE DIRECTIONALITY OF LATENT HARDENING BEHAVIOR IN ALUMINIUM SINGLE CRYSTALS

作　　者：王明章[1] 林实[1] 李成华[1] 肖纪美[1] 

机构地区：[1]北京科技大学材料物理系

出　　处：《固体力学学报》1996年第3期214-220,共7页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金

摘　　要：应用高纯铝单晶体．采用偏离弹性线法定义其潜在滑移系统的屈服应力，研究了潜在滑移系在正负两个滑移方向上的屈服及应变硬化行为．结果表明，潜在滑移系正负行为的差异要远远小于开动滑移系的Ｂａｕｓｃｈｉｎｇｅｒ效应，其正负方向的屈眼应力一般均等于或略小于预应变时的最大分切应力，大大高于开动滑移系的负向屈服应力；潜在滑移系和原始滑移系的相对取向及预应变的大小对单晶体潜在滑移系潜在硬化的影响不大，但对其起始过渡区应变硬化行为有一定的影响．根据实验结果，晶体塑性变形的硬化规律可近似表述为：除了开动滑移系的负向滑移系屈服应力很小外，其他潜在滑移系潜在硬化与开动滑移系自硬化基本相同．By defining the yield stress in a latent hardening test as the first deviation from the elastic straight line, the yielding and hardening behaviors of latent system in active and negative slip directions were studied in aluminium single crystal. It was shown that the yield stresses on both positive and negative latent systems are about equal to or a little lower than the maximum resolved shear stress in primary test, but much higher than that of the active system in reverse. The influence of relative orientation and prestrain on latent hardening initial work-hardening in secondary test was also investigated, and it was found that there is a considerable effect on initial work-hardening, but none on latent hardening. With reasonable approximation, a gardening rule for single crystal could be proposed based on experiment results, that is, except for the yield stress on the system negative to the active system is very low, hardening on other systems is nearly the same as self-hardening.

关 键 词：潜在硬化 应变硬化 塑性变形 单晶体 

分 类 号：O733.3[理学—晶体学]