STS321不锈钢的抗氧化性能

Anti-oxidation performance of STS 321 stainless steel

提出使用一种新的耐高温不锈钢STS321(Cr18Ni9Ti)用做中低温固体氧化物燃料电池(SOFC)的连接体,研究了其在空气中的循环氧化行为。在温度低于700℃时,不锈钢几乎不被氧化。在700～800℃时的氧化曲线为典型的抛物线,氧化活化能为105.4kJ/mol。在800℃氧化800h,在氧化初期的200h内形成氧化层保护膜后,其质量一直保持恒定。在温度达到900℃时,氧化膜保护层由于挥发而失去保护作用,外层开始脱落,不锈钢质量降低。表明STS321合金在抗氧化方面非常适合用作中低温SOFC(400～800℃)的连接体材料,而其他性能有待进一步探讨。

A promising high temperature-resistant stainless steel, STS 321 （Cr 18 Ni 9 Ti）, as interconnect of solid oxide fuel cell （SOFC） working at intermediate or low temperature was offered and its cycle oxidation property in air was investigated. The research results show that the steel is almost hardly oxidized in the condition of less than 700℃. The oxidation curves derived from 700---800 ℃ are typical parabolas and the oxidation active energy is 105.4 kJ/mol. The mass of steel is constant since oxidative protective scale produced at 800 ℃ 800 h. However, oxidative protective layer decomposed at 900 ℃ due to volatilization and detached from the steel substrate, lost shielding function, and the mass of the steel also decreased. The research demonstrates that STS 321 stainless steel is a promising interconnect candidate for intermediate and low temperature SOFC （400--800 ℃ ） in aspect of anti-oxidation at least. Other properties such as conductivity, dilation coefficient, etc., have to be measured further.