Phase constitution, microstructure and mechanical properties of a Ni-based superalloy specially designed for additive manufacturing

In this study, a kind of Ni-based superalloy specially designed for additive manufacturing (AM) was investigated. Thermo-Calc simulation and differential scanning calorimetry (DSC) analysis were used to determine phases their transformation temperature. Experimental specimens prepared by laser metal deposition (LMD) traditional casting method. Microstructure, phase constitution mechanical properties the alloy characterized electron microscopy (SEM), transmission (TEM), X-ray diffraction (XRD) tensile tests. The results show that contains two basic phases, ?/?’, in addition these at least secondary may be present, such as MC carbides Laves phases. Furthermore, as-deposited has finer dendrite, its mean primary dendrite arm space (PDAS) is about 30–45 ?m, average size ?’ particles 100–150 nm. However, as-cast much larger PDAS 300–500 ?m with even third arms. Correspondingly, displays different behavior processing methods, specimen shows better ultimate stress (1,085.7±51.7 MPa), yield (697±19.5 MPa) elongation (25.8%±2.2%) than specimen. differences are due morphology dendrites, ?’, phase, segregation elements, etc. Such important information would helpful application well new development.