Ti-Al双丝超音速电弧喷涂涂层的滑动磨损特性研究

为了提高铝合金(LY12)的表面耐磨性,采用钛、铝金属丝材和SAS-Ⅰ型超音速电弧喷涂设备,利用二次回归正交试验方法、有润滑滑动磨损试验、涂层显微组织和磨损表面形貌观察、XRD分析,定量分析了喷涂电压和喷涂距离对涂层滑动磨损体积的影响规律,并进行了喷涂工艺参数的优化及其与基体滑动磨损的对比试验.结果表明:在特定的磨损和喷涂条件下,当喷涂距离较小时,随喷涂电压的增大,涂层的体积磨损量逐渐减小;随着喷涂距离的增加,涂层的体积磨损量随喷涂电压的升高逐渐增大,并且喷涂距离越大,涂层的体积磨损量随喷涂电压增大的速率愈大.当喷涂电压比较低时,涂层的体积磨损量随喷涂距离的增大而降低,但是,随喷涂电压的逐渐升高,涂层的体积磨损量随喷涂距离的增大逐渐上升,并且,喷涂电压愈高,其随喷涂距离而增加的速率越快.当喷涂电压和喷涂距离分别为26V和0 236m时,涂层具有最佳的耐滑动磨损性能,根据该工艺参数制成的涂层,其滑动磨损体积仅为LY12铝合金的1/38.84.即在适当的工艺条件下,Ti-Al双丝超音速电弧喷涂涂层对LY12铝合金具有显著的表面耐磨强化作用.

Study of Slide Wear Resistance Properties of Coatings Ti-Al Twin Wires Ultrasonic Arc Sprayed

In order to strengthen the wear resistance in surface of aluminum alloy (LY12), coatings were manufactured by using titanium and aluminum wires and supersonic arc spraying systems of model SAS-I. The influence of arc spraying technological parameters on oil drip feed lubrication slide-wear resistance of coatings was studied by orthogonal regression experimental design method, then the slide wear properties of the coatings sprayed under optimum parameters conditions and the aluminum alloy matrix (LY12) was determined, the microstructure of the coatings and the character of worn surface were observed and analyzed by X-ray diffraction and scanning electric microscopy respectively. The results show that; the abrasive volume of coatings decreases with spraying voltage while the spraying distance is shorter, and increases with spraying voltage at the longer spraying distance, the longer the spraying distance, the higher the speed of coating abrasive volume increasing with spraying voltage; the abrasive volume of coatings decreases with spraying distance at lower spraying voltage, but with spraying voltage increasing, the volume of coatings increases with spraying distance and the more quickly the abrasive volume of coatings increasing with spraying distance. The abrasive volume of coatings sprayed by optimum parameters, such as 26V and 0.236m, is only equal to 1/38.84 of aluminum alloy (LY12). It is indicated that the coatings of Ti-Al twin wires ultrasonic arc spraying has excellent surface strengthening effect on aluminum alloy with optimum spraying parameters.