B-Ce复合微合金化对S31254超级奥氏体不锈钢组织和力学性能的影响

采用扫描电镜、拉伸试验等方法研究了B-Ce复合微合金化后S31254超级奥氏体不锈钢的组织和力学性能。结果表明,B、B-Ce 复合微合金化有利于抑制σ相的析出,改善σ相的析出形态,相同固溶工艺条件下,B-Ce复合微合金化后的试样更有利于σ相的完全回溶;相同时效工艺条件下,B-Ce复合微合金化抑制σ相析出的作用更明显。B及B-Ce复合微合金化后的试验钢拉伸断口处的韧窝更大更深,材料的伸长率也显著增加,说明微合金化有利于进一步提高S31254钢的韧性。

Effect of B-Ce composite microalloying on microstructure and mechanical properties of S31254 super austenitic stainless steel

Microstructure and mechanical properties of the S31254 super austenitic stainless steel after B-Ce composite microalloying was investigated by means of SEM and tensile tests. The results show that the B and B-Ce composite microalloying can inhibit the precipitation of σ phase and improve the precipitation morphology of σ phase. Under the same solution treatment conditions, the B-Ce composite microalloyed specimens are more conducive to the complete redissolution of σ phase. Under the same aging conditions, the B-Ce composite microalloying has a more obvious effect on inhibiting σ phase precipitation. The dimples at tensile fracture of the B and B-Ce composite microalloyed specimens are larger and deeper, and the elongation of the materials is also significantly increased, indicating that microalloying is beneficial to further improve the toughness of the S31254 steel.