超级双相不锈钢5A泵壳铸件裂纹缺陷分析与消除

Crack Defect Analysis and Elimination of Pump Casing Casting of Super Duplex Stainless Steel 5A Material

摘要: 分析了超级双相不锈钢5A泵壳铸件产生裂纹的原因,结果表明,铸件在铸型里缓慢冷却过程中,组织发生了铁素体的共析转变,铁素体相析出了σ相和二次奥氏体相,σ相是泵壳铸件产生开裂的主要原因,收缩应力和热应力的变化加剧了泵壳铸件开裂的倾向。采用热打箱+热装炉工艺或缓慢冷却＋缓慢升温工艺措施,有效地避免了泵壳铸件的开裂。
- 5A /
- 超级双相不锈钢 /
- 铸件 /
- 泵壳 /
- 裂纹 /
- σ相
Abstract: The causes of cracks in super duplex stainless steel 5 A pump casing castings are analyzed. It is found out that the structure of the casting undergoes eutectoid transformation of the ferrite phase in the slow cooling process in the mold. σ phase and secondary austenite phase precipitate from the ferrite phase, and the σ phase is the main reason for the cracking of pump casing castings. The change of contraction stress and thermal stress aggravate the cracking tendency of pump shell castings. The cracking of pump casing castings can be effectively avoided by adopting hot sand falling + hot charging furnace process or slow cooling + slow heating process.
- 5A /
- super duplex stainless steel /
- casting /
- pump /
- crack /
- σ phase

[1]	赵钧良.双相不锈钢铁素体含量控制及耐腐蚀性能的研究[J].上海钢研,2005(2):20-23.
[2]	郭海霞,张金民,夏申琳.铸态双相不锈钢彩色金相异常组织分析[J].理化检验(物理分册),2014,50(4):273-276.
[3]	韩英,邹德宁,李姣,等.双相不锈钢中σ相的析出及其数学模型[J].铸造技术,2009,30(6):820-823.
[4]	吴玖.双相不锈钢[M].北京:冶金工业出版社,1999.
[5]	杨银辉,严彪,郑鑫.双相不锈钢高温时效σ相析出行为研究进展[J].材料导报,2011,25(19):105-109.
[6]	赵志毅,徐林,李国平,等.超级双相不锈钢σ相析出及对组织性能的影响[J].材料热处理学报,2010,31(10):75-79.
[7]	罗照银,李静媛.S32760超级双相不锈钢中σ相的析出规律[J].材料热处理学报,2015,36(4):110-115.