超级双相不锈钢S32760凝固过程Thermo-Calc热力学软件的应用  

Application of Thermo-Calc Software during Solidification Process of Super Duplex Stainless Steel S32760

作　　者：王哨兵 周珠 孙文强 陈登武 李光恒 曹萍 Wang Shaobing;Zhou Zhu;Sun Wenqiang;Chen Dengwu;Li Guangheng;Cao Ping(Zhejiang Jiuli Hi-Tech Metals Co Ld,Huzhou 313000)

机构地区：[1]浙江久立特材科技股份有限公司,湖州313000

出　　处：《特殊钢》2020年第3期15-19,共5页Special Steel

摘　　要：利用Thermo-Calc热力学计算软件得到S32760(022Cr25Ni7Mo3WCuN)超级双相不锈钢凝固过程中的相图,确定了S32760双相钢是FA (铁素体-奥氏体)凝固模式,通过改变奥氏体和铁素体的形成元素的含量,确定在不同的化学成分下的热加工性能、Cr2N和σ相析出温度,得到S32760双相钢热加工温度区间随着奥氏体形成元素C、N、Ni、Mn含量的增加而变大,随着铁素体形成元素Si、Cr、Mo含量的增加而减小,而W对热加工性能没有影响。根据热力学计算,确定了最优的化学成分(/%:0.022C,0.30Si,0.80Mn,25.60Cr,6.20Ni,0.54Cu,3.50Mo,0.54W,0.27N),S32760双相钢最佳热塑性温度为1 195℃,Cr2N相的析出温度为1 050℃,σ相析出温度为1 020℃,热加工区间为145℃,并且通过了后续的现场实践验证。The phase diagram of S32760(022Cr25 Ni7Mo3 WCuN) super duplex stainless steel during solidification process is determined by Thermo-Calc thermodynamic calculation software,and the solidification mode of S32760 duplex steel is FA(Ferrite-Austenite).By changing the content of austenite and ferrite forming elements and the different chemical compositions to determine the hot working properties、Cr2 N and σ phase precipitation temperatures,the hot working temperature range of S32760 is enlarged with increasing the content of austenite forming elements C、N、Ni and Mn,and reduced with increasing the content of ferrite forming elements Si、Cr and Mo,however W has no effect on hot working performance.According to the thermodynamic calculation,the optimal chemical composition(/%:0.022 C,0.30 Si,0.80 Mn,25.60 Cr,6.20 Ni,0.54 Cu,3.50 Mo,0.54 W,0.27 N) is determined.The optimal thermoplastic temperature of duplex steel S32760 is 1 195 ℃,the precipitation temperature of Cr2 N phase is 1 050℃ and the precipitation temperature of σ phase is 1 020℃,and the hot working range is 145 ℃,which has been verified by subsequent production practice.

关 键 词：Thermo-Calc热力学计算 S32760超级双相钢 化学成分 40%奥氏体 Cr2N Σ相 

分 类 号：TG142.71[一般工业技术—材料科学与工程] TB115[金属学及工艺—金属材料]