In the present study, acicular ferrite nucleation and growth were investigated from a crystallographic point of view in API5L-X65 steel weld metals. It was observed that acicular ferrite was nucleated on inclusions in weld metal. The titanium-enriched layer around inclusions was characterised as the TiO phase by selected area diffraction patterns. A scanning electron microscope equipped with an electron backscatter diffraction technique was applied to investigate the crystallographic orientation relationship. The results showed that acicular ferrite lathes had a Baker–Nutting orientation relationship with the TiO layer on the inclusion surface in the nucleation of acicular ferrite. However, it is confirmed that the growth of acicular ferrite lathes depends on the deviation from the Kurdjumov–Sachs relationship between lathes and primary austenite.

中文翻译：

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API5L-X65钢埋弧焊接头针状铁素体形核和生长

在本研究中，从晶体学的角度研究了 API5L-X65 钢焊缝金属中的针状铁素体形核和生长。观察到针状铁素体在焊缝金属中的夹杂物上形核。夹杂物周围的钛富集层通过选定的区域衍射图表征为 TiO 相。应用配备电子背散射衍射技术的扫描电子显微镜来研究晶体取向关系。结果表明，针状铁素体车床在针状铁素体形核过程中与夹杂物表面的 TiO 层具有 Baker-Nutting 取向关系。然而，已证实针状铁素体车床的生长取决于车床与初生奥氏体之间的库德朱莫夫-萨克斯关系的偏差。