奥氏体钢晶间腐蚀机理电子理论研究

采用递归法计算了奥氏体钢的杂质掺入能、格位能、亲和能等电子结构参数，建立电子参数与奥氏体钢晶间腐蚀关系，探索晶间腐蚀机理。研究表明：奥氏体钢中S和P由晶内向晶界扩散，恶化晶界稳定性，且使电子从晶界流向晶内，造成晶界与晶内产生电位差，形成微电偶结构，发生晶间腐蚀。C和Cr具有较强亲和力，能在奥氏体钢晶界形成（Cr，Fe）23C6相。Ni提高C的格位能，降低C在奥氏体中的固溶度，促进（Cr，Fe）23C6的形成与长大，增加奥氏体钢的晶间腐蚀敏感性。Nb和Ti降低C的格位能，抑制（Cr，Fe）23C6的形成，提高奥氏体钢的抗晶间腐蚀能力。

The Electronic Theory Study on Intergranular Corrosion of Fe-- Mn-- Cr Alloy

To explore the imergranular corrosion mechanism of alloy, recursive method is used to calculate the atomic embedded energy, lattice point energy, affinity energy and other electronic structure parameters and then setting up the relationship between the electronic parameters and the intergranular corrosion of Fe--Mn--Cr alloy. S and P in Fe--Mn--Cr alloy diffuse from brain to boundary, spread to the grain boundaries and through grain boundary diffuse to the alloy surface, making the boundary being worsen, the electron spread to the brain from boundary result in the electric potential difference between them, forming micro electric dipole structure, the intergranular corrosion occurs. C and Cr with strong affinity can form （Cr, Fe） and C6 phase. Ni cell can improve the lattice point energy of C, reducing C in austenite of .solid solution degrees, promoting the formation and growth of （Cr, Fe）23C6, and then increasing the intergranular corrosion of Fe--Mn--Cr alloy. Nb and Ti reduce the lattice point energy of C, restrain the formation of （Cr, Fe）23C6, improve the Intergranular corrosion resistant ability