双相不锈钢的热脆性

来源期刊：中南大学学报(自然科学版)1993年第3期

论文作者：吴惕言 刘武 Riquier Y

文章页码：342 - 347

关键词：双相不锈钢; 压缩形变; 热脆性

Key words：duplex stainless steel; compression; hot embrittlement

摘    要：本文研究了铁素体(F)-奥氏体(A)双相不锈钢在950～1200℃单轴压缩时的热脆性,撕裂发生在F/A相界面,热裂倾向对温度十分敏感.通过塑性形变增大F/A界面总面积并改变铸态的魏氏体组织,可抑制热裂倾向.σ相降低钢的热塑性,但它在1000℃以上高温时溶解速度很快.在1000℃以下塑性形变可加速σ相和二次奥氏体(A′)的析出.

Abstract: Hot ductility of a super duplex stainless steel containing 25 pctCr,7 pct Ni and 3.6 pct Mo has been investigated during and after uniaxial compression in the temperature range between 950 and 1200℃.It was found that hot ductility of the continuous casting slab of the alloy is very sensitive to deformation temperature.Hot embrittlement of the as-cast alloy could be explained in terms of the decohesion of ferrite/austenite interface.Enlarging total area of F/A interface or modifying the morphology of widmanstatten structure by plastic de-formation will decrease the tendency towards failure during hot working.Sigma phase decreases hot ductility but the dissolving process of sigma phase at elevated temperatures is very fast for this alloy.Sigma phase and secondary austenite precipitation are enhanced greatly by hot working.