固溶温度对特超级双相不锈钢S33207组织及成分分布的影响

Effect of solid solution temperature on microstructure and composition distribution of hyper duplex stainless steel S33207

通过对特超级双相不锈钢S33207进行不同温度的固溶处理,采用SEM对S33207进行组织观察及奥氏体与铁素体两相中成分分布的分析,以及各自点蚀抗力当量（PREN）值的测算。结果表明：特超级双相不锈钢S33207在1100℃固溶处理时其σ相完全溶解,此时两相比例较为理想,接近1∶1。当温度为1130℃时,两相各自PREN值达到理想水平,此时材料具有较佳的耐点腐蚀性能。建议工业生产中选择1100~1130℃温度范围对此钢进行固溶处理。

Through solution treatment at different temperatures,the microstructure of hyper duplex stainless steel S33207 and the composition distribution of austenite and ferrite duplex phases was observed and analyzed by using SEM,and the pitting resistance equivalent numbers（PREN） of each phase were measured,respectively. The results show that the σ phase is completely dissolved for the solid solution treatment at 1100 ℃,and the proportion of austenite and ferrite is ideal,close to 1：1. When solid solution treated at 1130 ℃,both the two phases have ideal PREN values,and the steel has excellent pitting corrosion resistance. It is suggested that the solution treatment temperature range of 1100-1130 ℃ is selected for industrial production.