PVD coatings and their failure behavior under extreme high contact stresses

物理气相沉积(PVD)涂层可以战略性地应用于安装在可能发生严重磨损的区域的相对较小的冲压模具镶件上。这种方法很可能是必要的，因为PVD涂层比电镀或化学镀或氮化钢具有更高的硬度和耐磨性。实验室测试通常用于在实际生产应用之前对PVD涂层进行评估。层裂是PVD硬质涂层在冲压应用中的主要失效机制，在与实际生产不符的操作条件下进行的实验室试验中无法观察到这种情况。在拟议的研究中，将选择销-盘滑动磨损试验、球-板冲击疲劳试验和超高接触应力下附加滑动运动的扩展冲击疲劳试验作为模拟剥落失效磨损条件的加速实验室试验。

Physical vapor deposition (PVD) coatings can be strategically applied on relatively small stamping die inserts which are installed in the areas where severe wear may occur. This approach is most likely necessary because PVD coatings can have a much higher hardness and wear resistance than electroplated or electroless coatings and nitrided steels. Lab tests are usually used to evaluate the PVD coatings before actual production applications. Spallation is the main failure mechanism of PVD hard coatings in stamping applications, which can not be observed in lab tests conducted in operating conditions that do not correspond to actual productions. In the proposed research, pin-on-disc sliding wear tests, ball-on-plate impact fatigue tests, and extended impact fatigue tests with additional sliding motions under ultra high contact stress will be chosen as the accelerated lab tests to simulate the wear conditions of spallation failures.