A new test method based onmultipass scratch testing has been developed for evaluating the mechanical and tribological properties\r\nof thin, hard coatings. The proposed test method uses a pin-on-disc tribometer and during testing a Rockwell C diamond stylus is\r\nused as the ââ?¬Å?pinââ?¬Â and loaded against the rotating coated sample. The influence of normal load on the number of cycles to coating\r\ndamage is investigated and the resulting coating damage mechanisms are evaluated by posttest scanning electron microscopy. The\r\npresent study presents the test method by evaluating the performance of Ti0.86Si0.14N, Ti0.34Al0.66N, and (Al0.7Cr0.3)2O3 coatings\r\ndeposited by cathodic arc evaporation on cemented carbide inserts. The results show that the test method is quick, simple, and\r\nreproducible and can preferably be used to obtain relevant data concerning the fatigue, wear, chipping, and spalling characteristics\r\nof different coating-substrate composites. The test method can be used as a virtually nondestructive test and, for example, be used\r\nto evaluate the fatigue and wear resistance as well as the cohesive and adhesive interfacial strength of coated cemented carbide\r\ninserts prior to cutting tests.
Loading....