纳米压痕法测量Cu的室温蠕变速率敏感指数

把恒加载速率/载荷法（const.P·/P）和恒载荷法（const.P）相结合，提出了一个稳态加载和长时间保载的纳米压痕蠕变试验新方法.该方法不仅适用于高蠕变能力的低熔点材料，也适用于低蠕变能力和存在压痕尺寸效应的高熔点材料.用该方法确定Cu的室温蠕变速率敏感指数m为0.01，并发现其值不受加载段所用的P·/P值和达到的最大压入位移h-max的影响. 关键词： 纳米压痕 铜 蠕变 蠕变速率敏感指数

The measurement of creep rate sensitivity of copper at room temperature by using nanoindentation

A new nanoindentation creep test, i.e. a steady-state loading segment followed by the constant load for long period of time, has been proposed by combining a constant loading rate divided by the load (const.P·/P) with a constant load test (const.P). The method is applicable not only to the materials with lower melting temperature and higher creep ability, but also to those materials with higher melting temperature and lower creep ability and an indentation size effect. The strain rate sensitivity m of Cu at room temperature determined by the method is about 0.01. It is also found that the previous loading schemes, including the values of the P·/P used during loading segment and the maximum depths h-max at the end of the loading segment, have no obvious influence on the values of the strain rate sensitivity m.