Patent ID: 6328820
Filing Date: 2001-12-11
Classification: C22C,Y10S

Abstract:
A spring steel comprising, by weight,0.38-0.85% C;0.25-2.10% Si;0.2-1.0% Mn;not more than 0.035% P; andnot more than 0.035% S,wherein oxide inclusions in the spring steel have an average composition, by weight, specified as follows:35%.ltoreq.SiO.sub.2.ltoreq.75%;5.ltoreq.Al.sub.2 O.sub.3.ltoreq.30%;10%.ltoreq.CaO.ltoreq.50%; andMgO.ltoreq.5%, excluding 0%; andwherein the ratio of the depth of surface defects to the diameter of the spring steel is less than 1.0%.