文摘
Micro-ultrasonic sheet-metal forming using molten plastic as a flexible punch is a new microforming technology useful for manufacturing micro-stamped thin sheet metals. In this paper, we researched how time parameters influenced the forming replication ability of microchannel forming. Our experimental results show that the forming replication ability of the method was improved by extending the ultrasonic action duration time and maintaining pressure time. An appropriate ultrasonic action duration time was determined by assessing the melting time of the plastic powder used as a flexible punch; an appropriate maintaining pressure time was determined by assessing the coagulation time of the molten plastic punch. When the ultrasonic action duration time was 0.5 s and the maintaining pressure time was 1.5 s, the forming replication ability of the microchannel reached 97 %. With further increases in the time parameters, the forming replication ability stopped rising, and the forming method produced parts with defects at a lower forming efficiency. Through these experiments, we obtained a set of optimal process parameters for microchannel formation.