Investigation into the High Temperature Wear Resistance and Oxdiation of Wear Resistant Surface Coatings to Titanium Alloy

• Main Authors: Wei-Hong Liao, 廖偉宏
• Other Authors: Huei-Sen Wang
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/34456075050949185628

碩士 === 義守大學 === 材料科學與工程學系碩士班 === 96 === To investigate the oxidation resistance and .wear resistance to titanium under the high temperature operation, three PVD sputtered hard coatings (TiCN, TiAlN, AlCrN) are selected for evaluation. High temperature wear resistance (HTWR) test is conducted by a heated pin-on-disk machine with the three operation temperatures (room temperature, 150 ℃and 300℃). Oxidation resistance test is conducted by three high temperatures (900℃, 1000℃, 1100℃).heat treatment for the three coatings. As the tests are accomplished, surface observation of those samples (including hard coating and titanium alloy) is examined in a SEM with EDX facility. Diffusion of oxygen atoms into coatings is identified by the Glow Discharge Spectrometers, GDS). Coating structure before or after heat treatment is identified by the X-Ray Diffract meter (XRD). From the wear resistance test results, it can be found that TiCN does not work very well to titanium alloy under the room temperature. When the working temperature is elevated to 300℃, the coating starts to break down and tears off from the samples. For TiAlN coating, titanium is serious and discontinuous adhesive with the coating during HTWR process. These conditions become more serious if the wear test temperature going up, which results in the higher friction coefficient and substantially decreases the precision of work pieces. Compared to the previous two coating, AlCrN performs the better oxidation resistance and high temperature wear resistance. It can be observed that the coating still in acceptable condition after 1100℃heat treatment. For HTWR tests, it performs the better anti-adhesive nature to the titanium under the room temperature operation. If the test temperature is increased, the adhesive titanium on the coating is occurred. However, such adhesive is continuously which tends to create the better surface finish and working precision.