| 摘要 |
PURPOSE:To improve thermal fatigue crack resistance by heating the build-up layer of a build-up welded 13 Cr roll to specific temp. then cooling the same quickly thereby annihilating the softened area of the build-up welded roll. CONSTITUTION:A roll for continuous casting installations is manufactured by rolling, casting, centrifugral casting and build-up welding, and the 13 Cr alloy steel contg. 0.08-0.15% C, 0.15-0.60% Si, 0.3-1.5 Mn, 0.2-5.0% Ni, 10-14% Cr, <=4% Cu, <=1% Mo, <=0.5% V, <=0.5% N, <=0.05% B, <=0.03% P and <=0.03% S is used for the material thereof. The surface of this roll is build-up welded. The build-up part on the same circumference of this roll is heated to an Ac3 transformation point -Ac3 transformation point +100 deg.C temp. range by high frequency induction heating, after which it is quickly cooled, whereby the softened area of the build-up welded part is annihilated and the generation of thermal fatigue cracks is prevented. |
