Laser powder bed fusion of a new high gamma prime Ni-based superalloy with improved weldability

• DOI: 10.1016/j.matdes.2021.109895
• Publication Date: 2021-06-10T16:25:47Z
• Authors: Ashutosh Jena; Sila Ece Atabay; Alexandre Gontcharov; Paul Lowden; Mathieu Brochu
• Keywords: Tensile testing

This study reports the crack-free fabrication of a new high gamma prime precipitation hardened Ni-based superalloy by Laser Powder Bed Fusion (LPBF) process. In as-built condition, scanning electron microscopy and backscattered diffraction analysis indicated presence elongated columnar grains with an orientation along 〈1 0 0〉 direction. Following sub-solvus heat treatment cycle determined using Thermo-Calc software, microstructure was observed orientation. High-resolution microscope revealed bimodal distribution precipitates uniform carbide in heat-treated samples. As result treatment, hardness increased from 365 HV to 508 HV. The samples also displayed excellent yield strength, ultimate tensile elongation 939 MPa, 1368 23% respectively at room temperature. Mechanical testing elevated temperatures confirmed reached 80 106 34% 1121 °C. stress rupture test good creep properties times 559 h 75 h, respectively, 927 °C 982 °C, for stresses 152 MPa 138 MPa.