【摘要】 研究了Si含量对9Cr型铁素体马氏体（F/M）钢析出相和力学性能的影响。结果表明：在不同Si含量的9Cr型F/M钢中析出相均为M₂₃C₆、MX和Laves相，Si能促进Laves相和M₂₃C₆型碳化物的析出。Si含量为0.9%～1.2%的这种钢其拉伸强度和延伸率略有降低，冲击性能维持稳定；Si含量为1.2%～1.8%时，Si的固溶强化和析出相的沉淀强化使钢的拉伸强度提高。但是，随着Si含量的进一步提高Laves相和M₂₃C₆型碳化物大量析出，使其冲击功显著衰退。更多还原

【Abstract】 Ferritic martensitic （F/M） steel is one of the main candidates for structural components of lead-bismuth fast reactors.Increasing the Si content can enhance the resistance of the material to Pb-Bismuth corrosion,but it also affects the precipitation behavior of precipitates and mechanical properties of the material.In this paper,four ingots of F/M steels with different Si contents （0.9%,1.2%,1.5%and1.8%by mass fraction） were vacuum melted and cast,and then forged to generate blocks,afterwards,the steels were subjected to the following heat treatment process:water cooling after solution treatment at 1050℃for 30 min,and then air cooling after tempering at 760℃for 90 min.The effect of the Si addition on the precipitation behavior of precipitates and mechanical properties of 9Cr type F/M steel was carefully examined.The results show that the precipitated phases of 9Cr type F/M steel with different Si contents are M₂₃C₆,MX and Laves phases,and the presence of Si can promote the precipitation of Laves phase and M₂₃C₆ carbide.When the Si content is 0.9%～1.2%,the tensile strength and elongation of the steel are slightly reduced,and the impact performance remains stable;when the Si content is 1.2%～1.8%,the solid solution strengthening of Si and the precipitation strengthening of the precipitates make the strength of the steel increase,but with the increase of Si content,Laves phase and M₂₃C₆ type carbide precipitates a lot,and the impact energy decreases significantly.更多还原