Magnetostrictive coat forming method, magnetostrictive torque sensor manufacturing method, and electric power steering apparatus including such a sensor

摘要

For forming an annular magnetostrictive coat (16, 17) on an outer peripheral surface of a rotational shaft (11) associated with a magnetostrictive torque sensor, a magnetostrictive-coat forming method comprises a step of fitting a cylindrical masking jig (16, 17) over the outer peripheral surface of the rotational shaft (11) and securing the masking jig to the outer peripheral surface, a step of placing the rotational shaft in a plating tank (25) to thereby form the magnetostrictive coat by plating on the outer peripheral surface, and a step of detaching the masking jig (16, 17) from the rotational shaft (11).