国产新型高氮不锈钢耐腐蚀性能研究

Study on anticorrosion property of novel domestic high-nitrogen stainless steel

[目的]高氮不锈钢具有高强韧、抗疲劳、耐磨损、耐腐蚀等优点,在航空航天、机械制造、石油化工和海洋工程领域备受关注。国内在研发高氮不锈钢过程中主要关注其制备工艺、组织结构及力学性能,耐蚀性方面的研究较少。[方法]在不同温度(280、595和630°C)下对国产30Cr15Mo1N高氮不锈钢材料进行回火处理,得到二次析出相尺寸不同的组织。通过电化学测试、浸泡腐蚀试验和中性盐雾试验,结合形貌分析,研究了高氮不锈钢的二次析出相对其耐蚀性的影响。[结果]随回火温度升高,30Cr15Mo1N高氮不锈钢中的二次析出相增加、尺寸增大。280℃回火处理的30Cr15Mo1N高氮不锈钢在不同介质中的腐蚀速率最低,具有最优异的耐电化学腐蚀和盐雾腐蚀性能。[结论]析出相对30Cr15Mo1N高氮不锈钢的腐蚀行为具有重要影响,析出相尺寸增大对其耐蚀性不利。

[Introduction]High-nitrogen stainless steel is highly regarded in fields of aerospace,machinery manufacturing,petrochemistry,and marine engineering due to its advantages i.e.high strength-toughness,fatigue resistance,wear resistance,and corrosion resistance.Much attention has been paid to the preparation process,microstructure,and mechanical properties of high-nitrogen stainless steel during its research and development in China,while there are few studies on its corrosion resistance.[Method]The domestic 30Cr15Mo1N high-nitrogen stainless steels with different sizes of precipitated phases were obtained by tempering at different temperatures(i.e.280℃,595℃,and 630℃).The effect of precipitated phase on the corrosion resistance of 30Cr15Mo1N high-nitrogen stainless steel was studied by electrochemical test,immersion corrosion test,neutral salt spray test,and morphology analysis.[Result]The precipitated phase in 30Cr15Mo1N high-nitrogen stainless steel became more and larger with the increasing of tempering temperature.The high-nitrogen stainless steel tempered at 280℃ featured the lowest corrosion rate in different mediums,and the best resistance to electrochemical corrosion and neutral salt spray corrosion.[Conclusion]The precipitated phase has great impact on corrosion behavior of 30Cr15Mo1N high-nitrogen stainless steel,and the increase of precipitated phase in size is not conducive to its corrosion resistance.