The methods of transmission and scanning electron microscopy are used to study the evolution of the structure of a welded joint of steels 32G2 and 40KhN in the thermomechanically affected zone (TAZ) under rotary friction welding (RFW). EBSD analysis is used to certify the microstructure in different parts of the TAZ and to calculate the densities of the low- and high-angle boundaries. It is shown that complex processes of dynamic recrystallization combining several mechanisms develop in all these regions of the TAZ. Typical differences in the structures of the mobile (steel 40KhN) and immobile (steel 32G2) parts of the billets are described.

中文翻译：

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旋转摩擦焊接过程中碳钢焊接接头热机械影响区组织的演变

使用透射电子显微镜和扫描电子显微镜的方法研究了32G2和40KhN钢在旋转摩擦焊接（RFW）下在热机械影响区（TAZ）中的焊接接头的组织演变。EBSD分析用于验证TAZ不同部分的微观结构，并计算低角度和高角度边界的密度。结果表明，在TAZ的所有这些区域中，结合了多种机理的动态重结晶的复杂过程得以发展。描述了钢坯的活动部分（40KhN钢）和静止部分（32G2钢）的典型结构差异。