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相对较小的冲压模具镶件上，这些镶件安装在可能发生严重磨损的区域。这种方法很可能是必要的，因为PVD涂层可以具有比电镀或化学镀涂层和氮化钢高得多的硬度和耐磨性。实验室测试通常用于在实际生产应用之前评估PVD涂层。溅射是PVD硬质涂层在冲压应用中的主要失效机制，这在与实际生产不对应的操作条件下进行的实验室测试中无法观察到。在拟议的研究中，销-盘滑动磨损试验，球-板冲击疲劳试验，并在超高接触应力下的附加滑动运动的扩展冲击疲劳试验将被选为加速实验室试验，以模拟磨损条件下的speed-failed。

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.