气阀钢摩擦焊焊缝的组织结构

Microstructure of friction welded seam of valve steels

气阀钢２１－１２Ｎ与４Ｃｒ１０Ｓｉ２Ｍｏ的摩擦焊焊缝存在机械混合区、微扩散区和局部区域的相变区，但不存在熔化区。在强烈机械变形作用下，紧靠摩擦焊接触面两侧为超细微晶或细晶区，接着是再结晶区、回复区和形变区。但它们在接触面两侧的具体情况并不完全相同。

There are mechanically mixed zones,micro-diffusion zones and locally transformed zones but no melted one found in the friction welded seam of 21-12N to 4Cr10Si2Mo steels.Under a strong plastic deformation,an ultra microcrystalline or fine-grained zone was formedclose to the two sides of interface in the friction welded seam,and it was followed byrecrystallization zone, recovery zone and deformation zone.However,the microstructuralchanges at each side of the interface are different after friction welding.