HOLLOW RACK BAR AND METHOD FOR MANUFACTURING HOLLOW RACK BAR

摘要

PROBLEM TO BE SOLVED: To enhance a fatigue strength by imparting a compressive residual stress to the inner circumferential surface of a hollow material to improve durability. SOLUTION: A hollow rack bar 10 made of steel includes a hollow axis part 11 with a tooth part 12 meshing with a pinion gear and an end 13 provided on the inner circumferential surface of at least one end of the axis part 11 and formed with a screw part to be connected with a ball joint. Treatment is applied to the inner circumferential surface of the axis part 11 by shot peening and a compressive residual stress is imparted thereto. COPYRIGHT: (C)2011,JPO&INPIT