| 摘要 |
PURPOSE:To improve strength and improve durability by subjecting the thin wall and opening part of an outer race other than its ball rolling groove and internal spherical surface beforehand to anticarburization treatment, then to carburizing and hardening. CONSTITUTION:A process for production of an outer race wherein the outer race of a BIRFIELD type constant-velocity joint is subjected to hardening for imapartion of residual compressive stress to the ball rolling groove thereof. More specifically fire clay 6 is stuck to prescribed thickness on the design area of the outer side surface 2 and the opening part 5 of an outer race 1, whereby an anticarburization area 7 is formed. Next, this outer race 1 is subjected to carburizing and hardening by using a known gas carburizing and hardening device, then in the area 7, the carburization treatment does not take place and a stress-strain change by hardening occurs in the outer parts, particularly, thin walled parts, whereby the residual compressive stress corresponding to the expanding diameter component of a ball inserting part 4' is formed after cooling. |
