【摘要】 以激光熔覆法在低硅钢表面制备出高硅含量的Fe-Si涂层.用扫描电镜、透射电镜、M(?)ssbauer谱、X射线衍射等方法研究了硅钢基体和熔覆涂层的微观组织和室温超精细结构及其变化,结果表明,涂层与基体结合良好,自结合界面起至熔覆涂层表面的显微组织依次为平面晶、柱状树枝晶和细小树枝晶组织;熔覆涂层中存在6种可区别的Fe原子组态;涂层中含Si主要相为α-Fe类型相,以无序固溶体形式存在,其相对含量占69.6%(体积分数);α-Fe类型相中随Fe原子近邻Si原子数的增加,同质异能移位值增大,超精细磁场值减小.更多还原

【Abstract】 Fe-Si coating with high silicon content was prepared by laser cladding method on low silicon steel surface.Microstructure,hyperfine structure and structural transformation in laser cladding coating were investigated by SEM,TEM,MSssbauer spectroscopy and XRD.The results show that metallurgical bonding formed at the interface between Fe-Si coating and substrate,and existed planar,columnar and dendritic microstructures from the interface to the top surface of the coating.In the laser cladding coating,six different atom configurations of Fe atom are observed.The primary phase containing Si atom is corresponding to theα-Fe solid solution and its relative content is 69.6% (volume fraction).The isomer shift increases and the hyperfine magnetic field decreases as the number of nearest-neighboring Si atoms increases in theα-Fe phase.更多还原