Spring steel and spring having superior corrosion fatigue strength

摘要

A high-strength spring steel and a spring are provided that have superior corrosion fatigue strength. The spring steel comprises, in mass percent, 0.35-0.55% C, 1.60-3.00% Si, 0.20-1.50% Mn, 0.10-1.50% Cr, and at least one of 0.40-3.00% Ni, 0.05-0.50% Mo and 0.05-0.50% V, the balance being substantially Fe and incidental elements and impurities.

主权项

1. A steel alloy comprising, in terms of percent by mass:
0.47 to 0.49% C; 2.10 to 2.40% Si; 0.40 to 0.50% Mn; 0.20 to 0.30% Cr; 0.40-0.60% Ni; 0.05-0.20% Mo and 0.05-0.20% V; the balance being substantially Fe and incidental elements and impurities, and wherein the following formulas (6)-(8) are satisfied:
0.730%≦C(%)+Mn(%)/6+Si(%)/24+Ni(%)/40+Cr(%)/5+Mo(%)/4+V(%)/14≦0.780%  (6);0.630%≦C(%)+Mn(%)/6+Si(%)/24≦0.670%  (7); and1.35%≦Si(%)−0.46C(%)−1.08Mn(%)  (8).