Li Kuanhe, Wang Xianglong, Chen Haishao, Huang Xiaoxiao, Zhu Guanglin, Tu Ganfeng
School of Metallurgy, Northeastern University, Shenyang 110819, China.
Mining and Materials Engineering, McGill University, 3610 University Street, Montreal, QC H3A 0C5, Canada.
Materials (Basel). 2023 Mar 28;16(7):2699. doi: 10.3390/ma16072699.
Due to their light weight and outstanding mechanical properties at high temperatures, TiAl-based intermetallic alloys have driven increasing interest from both academia and industry; however, when additive manufacturing (AM) is applied to them, the outcome is hardly satisfying. In this work, we report a crack-free TiAl-based alloy fabrication by laser powder bed fusion (LPBF) using a mixture of a commercial Ti-48Al-2Cr-2Nb powder and a pure Ti powder. With the aid of a high cooling rate during LPBF, the as-built sample shows a ductile β phase with some partially-melted particles. After the heat treatment, partially-melted particles were dissolved, and the sample showed equiaxed α precipitates in the β matrix. The hardness was 515 ± 38 HV in the as-built sample and 475 ± 37 HV in the heat-treated sample. This study shows a novel strategy to fabricate crack-free TiAl-based alloy using LPBF from powder blends.
由于其重量轻且在高温下具有出色的机械性能，TiAl基金属间化合物合金引起了学术界和工业界越来越多的关注；然而，当将增材制造（AM）应用于它们时，结果却不尽人意。在这项工作中，我们报告了一种通过激光粉末床熔融（LPBF）使用商业Ti-48Al-2Cr-2Nb粉末和纯Ti粉末的混合物制造无裂纹TiAl基合金的方法。借助LPBF过程中的高冷却速率，增材制造后的样品显示出具有一些部分熔化颗粒的韧性β相。热处理后，部分熔化的颗粒溶解，样品在β基体中显示出等轴α析出物。增材制造后的样品硬度为515±38 HV，热处理后的样品硬度为475±37 HV。本研究展示了一种使用LPBF从粉末混合物中制造无裂纹TiAl基合金的新策略。
