METAL COIL SPRING AND PRODUCING METHOD THEREOF

摘要

PURPOSE:To improve strength by aligning the fiber direction of metal material as strand with the direction of main stress produced in a spring. CONSTITUTION:A torsional process T is added to the production process I of rolled metal material 1 and after the fiber direction F1 of the metal material 1 is directed at an angle alpha to the center line X-X of the metal material, a metal coil spring is formed of the metal material 1 as strand. The fiber direction F1 is selected to align with the direction of main stress produced on the surface of the strand when the coil spring is subjected to a load.