超声辅助等离子弧堆焊Ni60AA涂层相控阵超声检测和性能的研究

Phased Array Ultrasonic Testing and Performance of Ni60AA Coating by Ultrasonic-assisted Plasma Arc Surfacing

对采用超声辅助等离子弧堆焊方法制备的Ni60AA涂层进行相控阵超声检测,并结合实验方法分析堆焊层的微观组织、显微硬度和磨损特性.研究结果表明:相对于TOFD探头扫描,PA扇形扫描和直探头线性电子扫描更有利于对单道堆焊焊缝进行检测.在等离子堆焊时辅以超声波振动,有助于减少焊接缺陷,并且随着超声功率的不断增大,堆焊试样出现的缺陷也由多变少,缺陷种类也由较大的未熔合缺陷过渡到小的气孔和夹杂缺陷,堆焊区组织更细小且分布均匀,显微硬度和耐磨性均得到大幅提高.而当超声波功率增大到800 W时,未发现明显缺陷,焊接质量最好.相控阵超声检测对堆焊层的缺陷检测检出率较高,比常规超声检测更加直观和形象.

Phased array ultrasonic testing was carried out on Ni60AA coatings prepared by ultrasonic-assisted plasma arc surfacing method.The microstructure,microhardness and wear characteristics of surfacing layers were analyzed with experimental methods.The research results show that compared with the TOFD probe scanning,the PA sector scanning and the straight probe linear electronic scanning are more conducive to the detection of single-pass surfacing welds.Ultrasonic vibration is supplemented in plasma surfacing welding,which helps to reduce welding defects.With the continuous increase of ultrasonic power,the defects in the surfacing samples also decrease from large unfused defects to small pores and inclusion defects,and the structure of the surfacing area is finer and evenly distributed.Both microhardness and wear resistance are greatly improved.When the ultrasonic power increases to 800W,no obvious defects are found,and the welding quality is the best.Phased array ultrasonic testing has a higher detection rate of defects in the surfacing layer,which is more intuitive and visual than conventional ultrasonic testing.