N2分压对ZrN/WN纳米多层膜缺陷性质与力学性能的影响

利用射频磁控溅射系统在不同N₂分压的条件下，制备了一系列ZrN/WN纳米多层膜.借助慢正电子湮没技术分析了样品的缺陷性质，采用纳米压痕仪研究了多层膜的力学性能.结果发现：N₂分压为0.4Pa的多层膜具有最小的空位型缺陷浓度，其中心层和膜基结合层的平均S参数分别为0.4402和0.4641，而较低或较高的N₂分压都可能导致空位型缺陷浓度的增加.随着空位型缺陷浓度的减小，多层膜的硬度和临界载荷增大.对于空位型缺陷浓度最小的多层膜，其硬度和临界载荷达到最大值，分别为34.8GPa和100mN，说明较低的缺陷浓度有利于提高多层膜的力学性能. 关键词： ZrN/WN纳米多层膜 缺陷性质 力学性能 慢正电子湮没

Effect of N2 partial pressure on the defect properties and mechanical behaviors of nanoscale ZrN/WN multilayers

ZrN/WN nanoscale multilayer coatings were synthesized with different N₂ partial pressure by radio frequency magnetron sputtering. The vacancy-defect properties were measured by slow positron annihilation, and mechanical behaviors were studied using nanoindentation. The results indicate that the multilayer coating with N₂ partial pressure of 0.4 Pa has the lowest concentration of vacancy-defects, and the average S-parameters of the central and the combination layers are 0.4402 and 0.4641, respectively. Lower or higher N₂ partial pressure results in an increase in vacancy-defect concentration. With vacancy-defect concentration decreasing, the hardness and critical load of multilayer coatings increase. The multilayer coating with lowest concentration of vacancy-defects also exhibits maximum hardness and critical load (34.8 GPa and 100 mN). The decrease of vacancy-defect concentration is helpful to improve the mechanical properfies of multilayer coatings.