| 摘要 |
PURPOSE:To prevent generation of streaky flaws on the surface of worked product, by expanding and upsetting continuous casting blank material of stainless steel and superalloy, and after reheating, extruding using a reverse tapered die. CONSTITUTION:In manufacturing pipes or round bars by extruding continuous casting blank material of stainless steel or superalloy, hollow continuous casting blank material as a blank material for pipes or solid continuous casting blank material as a blank material for round bars is expanded or upset to give sufficient work strain and at the same time reheated to make coarse casting texture minute. Next, the fine texture continuous casting blank material is extruded using a reverse tapered die 14 of convex shape with an angle beta to the direction of extrusion to manufacture pipes or round bars. As the texture is made fine, streaky flaws do not occur on the surface of extruded pipes or round bars and product yield is improved. |
