PURPOSE:To improve wear resistance and accident resistance, by incorporating specific amounts of W to a roll stock with a specific composition, by limiting respective contents of P and S, and also by specifying the value of (V+W)/C. CONSTITUTION:This roll stock is a steel which consists of, by weight, 0.5-1.5% C, 0.1-1.5% Si, 0.2-1.6% Mn, 3.5-6.0% Cr, 0.1-0.5% Mo, 0.3-2.0% V, 0.2-1.0% W, =0.025% P, =0.025% S, and the balance Fe and contains, if necessary, 0.1-1.0% Ni and in which the value of (V+W)/C is regulated to 1.0-2.0. In this steel, similarly to Mo and V, W is a hard carbide-stabilizing element and it forms hard carbide and is dispersedly precipitated in a matrix, so that wear resistance is improved and, moreover, a characteristic phenomenon in which Charpy absorbed energy is higher than that in a steel of the same hardness is observed. P content is limited because P promotes embrittlement, and S content is also limited for the purpose of improving fatigue resistance and accident resistance because S increases inclusions and deteriorates toughness.
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