铜沉淀提高铸造马氏体不锈钢耐空蚀性能研究

Study on Improving Anti-Cavitation Resistance of Casting Martensite Stainless Steels by Cu Precipitation

针对普通马氏体铸造不锈钢在含氯离子溶液中耐点蚀和耐空蚀能力不足的问题,自行设计冶炼了一种经铜沉淀硬化的马氏体铸造不锈钢。通过力学性能测试、动电位极化扫描空泡腐蚀试验并结合SEM分析,研究了热处理工艺和铜含量对自行设计冶炼MSB马氏体不锈钢耐空蚀性能的影响。结果表明经铜沉淀的铸造马氏体不锈钢在3%NaCl溶液中的耐点蚀性能优于普通奥氏体不锈钢1Cr18Ni9Ti和高锰铝青铜,铜含量对铸造马氏体不锈钢的耐点蚀性影响不大。热处理工艺对铸造马氏体不锈钢耐空蚀性能有较大影响,时效温度越高,耐空蚀性能越差。当铜的质量分数在1.5%～2.5%之间时可以获得较好的强化效果,不锈钢的耐空蚀性能最好。

According to the insufficient of corrosion resistance of martensite stainless steel in the solutions containing CI-, a kind of casting martensite stainless steel was designed and melted. The anti-cavitation performance of the MSB martensite stainless steel was studied with the methods of mechanical performance measurement, potentiodynamic polarization, immersion test, cavitation test.an6 SEM analyses. The results showed that the pitting corrosion resistance of the casting MSB martensite stainless steel was better than 1Crl8Ni9Ti and ZQAl12-8-3-2. With the aging temperature rising, the lower hardness led to the weaker resistance to cavitation The weight percent of Cu in the stainless steel had little effect on the pitting resistance in 3% NaCl aqueous solutions, but large effect on the cavitation resistance. When the weight percent of Cu in the stainless steel was among 1.5% - 2.5%, the stainless steel had the best anti-cavitation properties.