COLD DRAWN HARD STEEL WIRE EXCELLENT IN TWISTING PROPERTY AND FATIGUE PROPERTY

摘要

PURPOSE: To obtain a cold drawn hard steel wire excellent in twisting properties and fatigue properties by subjecting stock with a tempered lower bainitic structure of a carbon steel or a high-medium low allay steel having a specified compsn. to cold wire drawing. ;CONSTITUTION: Steel wire stock with a tempered lower bainitic structure having a compsn. contg., by weight, 0.3 to 1.2% C, ≤1.2% Si and ≤2% Mn if required, comopositely added with one or more kinds amongil% Cu≤1% Ni, ≤2.0% ≤0.3% Nb, ≤0.3% V, ≤0.5% Mo and ≤0.01% B is subjected to cold wire drawing. Thus, from the morphology and scattering form of fine carbides, working hardenability owing to high ferrite can be obtd. by the cold wire drawing. As a result, the wire rod after the cold wire drawing is excellent in twisting properties in spite of its high tensile strength and is high in bending fatigue strength as well.;COPYRIGHT: (C)1995,JPO