The grain refining impact of Ti in additively manufactured steels as well as the outstanding formability of high-Mn steels owing to their low stacking fault energy (SFE) has been confirmed in the literature. In the current work, Ti and Mn were inoculated simultaneously to the stainless steel 316 L by laser powder bed fusion (LPBF) in-situ alloying. The local accumulation of the additions developed complexes of Ti-rich brittle phases that improved strength. Microstructural observations revealed the formation of intermetallic chunks of FeTi (bcc), σ (tetragonal), and C14 Laves phase (hcp) surrounded by emerged ferrite grains within the austenite. The rapid solidification of the molten tracks induced significant thermal stresses, which were responded by the generation of geometrically necessary dislocations (GNDs) at the austenite/ferrite interfaces, and activation of synchroshear mechanism within the Laves phase along with thermally activated slip systems in FeTi phase. Mn addition contributed to higher interface cohesion by facilitating dissociation of dislocations.

Ti 在增材制造钢中的晶粒细化影响以及高锰钢由于其低堆垛层错能 (SFE) 而具有出色的可成形性已在文献中得到证实。在目前的工作中，Ti和Mn通过激光粉末床熔合（LPBF）原位合金化同时孕育到不锈钢316 L中。添加物的局部积累形成了富钛脆性相的复合物，从而提高了强度。微观结构观察揭示了 FeTi ( bcc )、σ (四方) 和 C14 Laves 相 ( hcp ) 金属间化合物块的形成) 被奥氏体内出现的铁素体晶粒包围。熔融轨道的快速凝固引起显着的热应力，其响应是在奥氏体/铁素体界面处产生几何必要位错 (GND)，并激活 Laves 相内的同步剪切机制以及 FeTi 相中的热激活滑移系统. 通过促进位错的解离，Mn 添加有助于更高的界面凝聚力。