铝合金表面Ti-Al双丝超音速电弧喷涂涂层的组织与性能研究

利用SAS－1型超音速电弧喷涂设备和钛、铝丝在适当的工艺条件下，在LY12铝合金表面制成了钛铝合金复合涂层。并利用金相显微镜、X射线衍射仪、扫描电镜、X射线能谱仪、电子探针等，对涂层的成分、相结构、显微结构、孔隙率及其结合强度、显微硬度和耐磨性进行了研究。结果表明，利用超音速电弧喷涂设备，可以在铝基表面形成低孔隙率小于2.8%，结合强度为29MPa，显微硬度HV0.2为631和干滑动磨损体积仅为LY12基体1／7的TiAl合金涂层。显微组织观察发现，涂层与基体间有冶金结合的迹象，组织结构分析表明，涂层由TiN（TiO)，Al,Ti,TiAl,Ti3Al等相组成。涂层的磨损机制可能以化合物等硬质相的剥落引起的磨粒磨损和氧化磨损为主。

Study of Microstructure and Properties of Coatings of Ti-Al Twin Wires Ultrasonic Arc Sprayed Alloy on Aluminum Alloy Surface

By means of SAS 1 arc spraying equipment, Ti Al alloy compound coat systems were achieved on the LY12 aluminum alloy surface The relationship between composition, phase structure and microstructure of coatings and its bond strength, micro hardness, porosity and wear resistance, were analyzed with the optical metallurgical microscopy, SEM, XRD, EDX, EPMA The results show that the coatings of which porosity is less than 2 8%, microhardness is above HV 0 2 631, bond strength is 29MPa and dry wear abrasion volume is the same as one seventeenth its of the aluminum alloy matrix by the SAS 1 ultrasonic arc spray systems The metallurgical bond between coatings and substrates can be found by observation of microstructure The coatings consist of TiAl,Ti 3Al,TiN(TiO),Al,Ti The mechanism of coatings abrasion wear may be oxidative wear and grind wear because that the hard mass phases are departed from coatings