LEAF SPRING FOR VEHICLE AND METHOD OF MANUFACTURING THE LEAF SPRING

摘要

A leaf spring for vehicle capable of increasing a durability even if an inexpensive spring steel such as SUP9 and SUP11 is used as a material, wherein, while a spring body made of a spring steel having a Brinell hardness of 388 HBW to less than 555 HBW Brinell ball dent diameter of 3.10 mm to less than 2.70 mm is kept at a temperature of 150 to 400 °C, a first shot peening is applied to the tensile stress acting surface of the spring body with a load given thereto in the same direction as that for using the spring body.