特厚规格高等级管线钢X70热轧钢板的开发实践

摘要

Adopting a alloy design process of lower C-Mn-Mo-Nb series with right amount of micro-alloy elements such as V, Ti, Ni, Cu and Cr, and using clean steel smelting process and TMCP rolling process, developed successfully X70 thick and high grade pipeline steel heat roll plate. The results of analysis on micro structure and mechanical property showed that its structure was acicular ferrite admixture with ting grain and little inclusion, its band structure was light, and the precipitate was uniform diffusion. The X70 grade pipeline steel has high strength and excellent low temperature toughness.%采用低C-Mn-Mo-Nb系为基础，添加适量钒、钛、镍、铜和铬等微合金元素的合金设计方法，利用洁净钢冶炼技术和TMCP轧制工艺，研制开发了X70高等级厚规格钢板。对钢板组织和力学性能分析表明：钢板组织为针状铁素体混合组织，晶粒细小均匀，夹杂少，带状组织轻微，析出物均匀弥散，具有高强度和良好的低温韧性。