| 摘要 |
PURPOSE:To produce a suspension spring for an automobile having superior setting resistance at high temp. by hot or cold forming an N-contg. Mn-Cr low-alloy steel having a specified compsn. into a spring and by imposing setting strain on the spring by shearing strain at a specified temp. CONSTITUTION:A low-alloy steel contg., by weight, 0.40-0.85% C, 0.10-1.50% Si, 0.30-1.50% Mn, 0.10-1.00% Cr, <0.015% Al and 0.0060-0.0200% N is hot formed into a spring and this spring is hardened and tempered. A hardened and tempered steel wire may be cold formed into a spring. The resulting spring is heated to 80-400 deg.C and 0.005-0.030 setting strain is imposed on the spring by shearing strain at the temp. to produce a suspension spring for an automobile having superior setting resistance at high temp. |
