论文标题
WC单晶体在纳米引导下的变形机制：表面缺陷和方向对弹出式和滞后的影响
Deformation mechanism of WC single crystals under nanoindentation: Effects of surface defects and orientation on pop-in and hysteresis
论文作者
论文摘要
在基底（0001）和Prismatic（1010）平面上，使用Berkovich和Spherical Sunkes在单个负载和多载测试中，对纳米凹进进行了纳米吸引力。这项工作着重于将负载置换曲线相关联，包括弹性到塑性变形，尺寸效应和滞后效应与WC的变形行为。在不同的样品制备过程中，弹性到塑性变形在不同的阈值载荷下开始：发现该观察结果是由于表面位错密度的变化所致。观察到楼梯变形被认为是由脱位运动和滑动带的形成引起的。负载置换响应中的突然位移不连续性与位错环成核有关 - 发生在理论剪切强度或附近。此外，还使用载荷排化曲线的不连续性来确认磁滞回路是塑性变形的结果，因为它们纯粹是弹性时的。
Nanoindentation was carried out on pure tungsten carbide (WC) on the basal (0001) and prismatic (1010) planes, using Berkovich and spherical indenters, in both single load and multi-load testing. The work focuses on correlating the load-displacement curves, including elastic to plastic deformation, size effect and hysteresis with the deformation behaviour of WC. With different specimen preparation processes, the elastic to plastic deformation started at different threshold loads: This observation was found to be due to the variation in surface dislocation density. Staircase deformation was observed thought to be caused by dislocation motion and the formation of slip bands; sudden displacement discontinuities in the load-displacement response - associated with dislocation loop nucleation - occurred at, or near the theoretical shear strength. Furthermore, discontinuities in load-displacement curves were also used to confirm that hysteresis loops were a result of plastic deformation, as they when the loading was purely elastic.
