Abstract
In this study, warm forming die and blank holder could be heated and punch could be cooled always. At first, relation between die profile radius and drawing ratio was experimented in cylindrical cup drawing. Next, oil pan that is one of difficult part to press forming at room temperature was experimented and foreword experimental result was applied to die profile radius of oil pan. At last, warm forming of oil pan was continually examined. The results were following, (1) LDR of cylindrical cup drawing of warm forming were great than that of room temperature forming, but showed a violent variation with die profile radius, and fractures were in cup wall near to die profile. (2) An indication of good performance of warm forming was given with oil pan 1 stroke press, so oil pan from aluminum alloy sheets by warm forming had no fracture, but that by room temperature forming had fracture and that from steel sheets too. (3) Warm forming of oil pan from aluminum alloy sheets could be continued without break and mass productivity should be improve with insulation of handling machines.
