Abstract The grain structure and texture of metal parts fabricated by selective laser melting (SLM) are of interest for their effect on the properties. The study of the SLM single track can reduce the variables to be concerned and, hence, facilitate the understanding of the development of grain and texture in the SLM process. In this work, the austenitic stainless 316L single tracks are fabricated at different scanning speeds, and they are characterized by electron backscattered diffraction (EBSD) from transverse, serial transverse, and longitudinal cross-sections. It is validated that curved grain is common in the SLM single track. The effects of the varied thermal gradient and the shape of the melt pool on competitive growth of grain are analyzed. All the three equivalent orientations of the columnar grain are considered, which leads us to put forward a crystallographic feature of a favorable grain during the competitive growth in SLM. Such a crystallographic feature is validated by the texture of the SLM single track, especially the // scanning direction (SD) texture.

中文翻译：

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SLM 单轨的晶粒结构和纹理

摘要 通过选择性激光熔化 (SLM) 制造的金属零件的晶粒结构和织构因其对性能的影响而受到关注。对SLM单轨的研究可以减少所关心的变量，从而有助于理解SLM过程中纹理和纹理的发展。在这项工作中，奥氏体不锈钢 316L 单轨道以不同的扫描速度制造，它们的特征是从横向、连续横向和纵向截面的电子背散射衍射 (EBSD)。经验证，弯曲纹理在 SLM 单轨中很常见。分析了不同温度梯度和熔池形状对晶粒竞争性生长的影响。考虑了柱状晶粒的所有三个等效取向，这导致我们在 SLM 的竞争性生长过程中提出了有利晶粒的晶体学特征。这种晶体学特征通过 SLM 单轨的纹理得到验证，尤其是 // 扫描方向 (SD) 纹理。