Si含量对316H钢耐铅铋腐蚀性能的影响

316H钢具有较好的高温力学性能和耐腐蚀性能,是铅铋快堆主要候选结构材料.Si元素的加入会提升材料在铅铋中的耐蚀性,同时也会对组织产生影响.通过向316H钢中加入不同含量的Si元素,采用OM、SEM、XRD进行组织分析,对不同Si含量试验钢在550℃氧控的铅铋环境下进行动态腐蚀性能研究.结果表明,Si元素可有效提升31...

Effect of Si content on lead-bismuth corrosion resistance of 316H steel

As a main candidate material for LFR(lead-bismuth fast reactor), 316H has good high-temperature mechanical properties and corrosion resistance. The addition of Si can not only improve the corrosion resistance of 316H steel to liquid lead-bismuth eutectic (LBE), but also affect the microstructure. 316H steels with different Si contents were tested by OM, SEM and XRD at 550 ℃ in oxygen-controlled LBE environment to study the dynamic corrosion properties. The results show that Si can effectively improve the corrosion resistance of 316H steel to LBE. The thickness of oxide layer reduces from 450 μm to 30 μm by adding 2.0% (mass fraction) Si. The ferrite content increases in the microstructure and a large amount of carbides appear at the grain boundary by adding 4.5% (mass fraction) Si, which can reduce the corrosion resistance of the material. 316H steels with different Si contents exhibit difference in oxide layer structure. The oxide film containing SiO₂ in the inner layer can hinder the passage of elements, so as to improve the corrosion resistance to LBE.