短时固溶处理温度对SAF2507超级双相不锈钢点蚀行为的影响

Effect of Short Time Solid Solution Treatment Temperature on Pitting Corrosion Behavior of SAF2507 Super Duplex Stainless Steel

利用恒电位临界点蚀温度测试法和微观形貌观察法研究了短时固溶处理温度对SAF 2507超级双相不锈钢的微观形貌演变和点蚀行为的影响。结果表明,当固溶温度从1020℃提高到1150℃时,样品的铁素体的体积分数明显增加,而铁素体中的铬、钼等元素含量逐渐降低。SAF 2507超级双相不锈钢的临界点蚀温度(CPT)随着短时固溶处理温度的增加先升高后降低,在1100℃达到最大值。

The effects of short time solid solution treatment temperature on the microstructure evolution and pitting corrosion behavior of SAF2507 super duplex stainless steel were studied by means of the constant potential critical pitting temperature test method and the microscopic morphology observation method. The results indicate that when the solution treatment temperature increases from 1020 to 1150℃, the volume fraction of the ferrite in the sample increases obviously, while the contents of chromium, molybdenum and other elements decrease gradually. The critical pitting temperature （CPT） of SAF2507 super duplex stainless steel increases firstly and then decreases with the increase of short time solid solution treatment temperature, and reaches the maximum at 1100℃.