| 摘要 |
<p>A high strength steel plate for high heat input welding is provided to control the composition and micro-structure of molten steel in high heat input welding efficiently, thereby improving tensile strength, elongation ratio, hardness and surface property of the steel plate. A high strength steel plate for high heat input welding is composed of C: 0.01~0.2 weight%, Si: 0.1~0.5 weight%, Mn: 1.0~3.0 weight%, Ti: 0.01~0.1 weight%, Ni: 0.5~3.0 weight%, B: 0.0003~0.01 weight%, Mo: 0.05~1.0 weight%, N: 0.004~0.008 weight%, P: 0.030 weight% or less, Al: 0.005~0.05 weight%, S: 0.030 weight% or less, O: 0.01~0.03 weight%, and the remnant Fe and inevitable impurities, wherein Ti, O, N, and B satisfy the relations, Ti/O=1.3~3.0, Ti/N=7~12, N/B=0.8~1.5, and (Ti+4B)/N=11~16, and Mn and S satisfy the relation, Mn/S= 220~400.</p> |
