Warm forging of 17-4PH stainless steel through ausforming process

摘要

From both points of the forgability and the properties of forged material, the ausforming process for 17-4 precipitation hardening(17-4 PH) stainless steel is compared with the conventional warm forging process. Ausforming brings out the excellent upsettability of material in warm working temperature, while the conventional warm forging leads the drastic decrease of workability at 400 deg C. The properties of forged material are examined with tensile test, impact test, delayed cracking test. The properties of forged material are examined with tensile test, impact test, delayed cracking test. The charpy impact value of the ausformed and directly aged (AU-AG) material are superior to that of the solution treated and aged(ST-Ag) material. It keeps nearly the same level from room temperature to -100deg C. The ausforming process is applied successfully to the production with multistage forging machine of various 17-4 PH stainless steel parts such as bolts, nuts and sensors.