摘要
研究了Ca处理对含Ti大线能量焊接非调质低合金高强钢的组织与性能的影响。Ca处理钢组织结构得到细化,大线能量焊接热模拟热影响区(HAZ)晶界铁素体生长被抑制,其钢板及HAZ的强韧性均得到有效提高。Ca处理使含Ti钢热影响区氧硫化物复合夹杂物由片条状转变成球状,并从TiMnOS占主导变为TiCaMnOS-Al_2O_3占主导,提高了晶内针状铁素体形核能力。
The influence of calcium(Ca) treatment on the microstructure and properties of non quenched-tempered high heat input welded Ti contained HSLA steel is studied in this paper. The microstrueture of Ca-treated steel is comparatively finer than non-Ca-treated steel, and the growth of grain boundary ferrite in simulated high heat input welding heat affected zone(HAZ) of Ca treated steel is restrained. Both the strength and toughness of as-rolled steel and HAZ of Ca treated steel are effectively improved. The Ca-treatment changes the shapes of oxysulfides from strip to globosity in the HAZ of Ti-contained steel, and the dominant type of oxysulfides changs from TiMnOS to TiCaMnOS- Al2O3. Tthis improves the nucleation ability of intra-granular acicular ferrite.
关键词
Ca处理
大线能量焊接
晶内针状铁素体
性能
calcium treatment, high heat input welding, intra-granular acicular ferrite, property