Lass Eric A, Stoudt Mark R, Katz Michael B, Williams Maureen E
Materials Science and Engineering Division, Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Dr., M/S 8555, Gaithersburg, MD, USA.
Scr Mater. 2018 Sep;154. doi: 10.1016/j.scriptamat.2018.05.025.
One drawback of the laser powder-bed fusion additive manufacturing (AM) technique is the build-up of residual stresses during processing that require a stress-relief heat treatment prior to components being removed from the build plate. Here, we demonstrate the coprecipitation of the -phase alongside the known -phase, during stress-relief annealing of AM Inconel 625 at 870 °C. The unexpected precipitation of in the AM material is attributed to the local solute enrichment to the interdendritic regions of the as-built solidification microstructure. Dissolution of the and phases is achieved after annealing for 15 min at 1150 °C.
激光粉末床熔融增材制造（AM）技术的一个缺点是，在加工过程中会产生残余应力，这就要求在将部件从构建板上取下之前进行消除应力的热处理。在此，我们展示了在870°C对增材制造的因科镍合金625进行消除应力退火期间，除了已知的γ相之外，还会共析出γ'相。增材制造材料中γ'相的意外析出归因于凝固微观组织的枝晶间区域出现局部溶质富集。在1150°C退火15分钟后，γ相和γ'相溶解。
