Experimental Investigation on Ultrasonic Vibration Assisted Helical Grinding of Internal Threads in SiCp/Al MMCs

Abstract:
Silicon carbide particle-reinforced aluminum matrix composite (SiCp/Al) has excellent properties and get increasingly used in aerospace and optics fields. However, due to the poor machining performance of SiCp/Al composite, the machining of internal threads is very difficult. To solve this problem, Ultrasonic vibration-assisted helical grinding method is used in this research to investigate the effect of thread machining. The grinding force, thread profile, thread root morphology, and wheel wear are measured in ultrasonic vibration-assisted grinding (UVAG) and conventional grinding (CG). The experimental results showed that the grinding force can be reduced by about 30% - 60% in UVAG. The thread profile and thread root surface quality in UVAG are better than CG. The surface roughness Ra of the thread root in UVAG is improved by 5% - 25% comparing to CG. Meanwhile, the micromorphology of the grinding wheels after machining 22 threaded holes shows that ultrasonic vibration can significantly reduce grinding wheel wear and improve the quality stability of thread machining. These results provide guidelines for achieving high machining efficiency and surface quality in the internal threads machining of SiCp/Al composites by ultrasonic vibration-assisted helical grinding in the engineering application.