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304不锈钢在143℃硅油中恒载荷预蠕变足够长时间后,再在143℃ MgCl2溶液中相同恒载荷下进行应力腐蚀.结果表明,在开路条件下应力腐蚀能使表层和体内α＇马氏体分别升高14％和1.5％.但如放在不发生应力腐蚀（VSCE=-600mV阴极极化）的沸腾MgCl2溶液中,则马氏体含量基本不变.测量了在不同恒电位的143℃ MgCl2溶液中形成钝化膜后产生的膜致内应力结果表明,当阴极电位VSCE<-550mV后,钝化膜应力为零或是压应力,同时亦未发生应力腐蚀;如VSCE>-550 mV,则随电位升高,钝化膜引起的拉应力也升高,与此同时,应力腐蚀敏感性也升高.因此,304不锈钢应力腐蚀促进马氏体相变和腐蚀钝化膜引起的附加拉应力有关.
304 stainless steel under constant load pre-creep in 143 ℃ silicone oil for a long enough time, and then subjected to stress corrosion under the same constant load in 143 ℃ MgCl2 solution.The results show that under the open-circuit stress corrosion can make the surface and in vivo α ’ Increased by 14% and 1.5% respectively, but the content of martensite did not change substantially if it was placed in boiling MgCl2 solution without stress corrosion (VSCE = -600mV cathodic polarization) ℃ MgCl2 solution after the formation of the film-induced internal stress results show that when the cathode potential VSCE <-550mV, passive film stress is zero or compressive stress, but also did not stress corrosion; such as VSCE> -550 mV, the tensile stress caused by passivation film also increased with the increase of potential, and at the same time, the sensitivity of stress corrosion increased.Therefore, the stress corrosion promotion of 304 stainless steel promotes the martensitic transformation and corrosion passivation film Additional tensile stress related.