Micro Rotary Plunge-Swaging of Stainless Pipes

摘要

Micro parts like medical catheters or end effectors require micro rotary swaging to process forming or joining. Higher strength or sophisticated inner features can be achieved through micro rotary swaging which are difficult for the micro machining or grinding process. This work focuses on examining the formability of micro pipes of AISI 304 stainless steel with micro rotary plunge-swaging. Both as-received and vacuum-annealed pipes with both furnace-cooling and water-cooling were tested. The micro hardness and grain size of the as-received and vacuum-annealed pipes were measured. The result shows that the as-received micro pipes need be annealed to be suitable for the micro swaging process. Best swaging result was obtained when annealing with a holding time of 45 minutes and furnace-cooling were used. The G2 workpiece is better than the G1 and the G3 workpieces. This is because the G1 workpieces experience more deformation due to thicker walls, and insufficient grain layers were formed in the G3 workpiece during the annealing.