US 12,186,803 B2
Nickel-based superalloy formed by selective laser melting and preparation method thereof
Haijun Su, Xi'an Shaanxi (CN); Yong Zhao, Xi'an Shaanxi (CN); Meng Wang, Xi'an Shaanxi (CN); Jun Zhang, Xi'an Shaanxi (CN); Min Guo, Xi'an Shaanxi (CN); Lin Liu, Xi'an Shaanxi (CN); and Hengzhi Fu, Xi'an Shaanxi (CN)
Assigned to Northwestern Polytechnical University, Xi'an Shannxi (CN)
Filed by Northwestern Polytechnical University, Xi'an Shaanxi (CN)
Filed on Mar. 3, 2022, as Appl. No. 17/685,824.
Claims priority of application No. 202110235894.2 (CN), filed on Mar. 3, 2021.
Prior Publication US 2024/0189897 A1, Jun. 13, 2024
Int. Cl. B22F 1/05 (2022.01); B22F 1/142 (2022.01); B22F 3/10 (2006.01); B22F 3/105 (2006.01); B22F 9/04 (2006.01); C22C 19/05 (2006.01)
CPC B22F 1/05 (2022.01) [B22F 1/142 (2022.01); B22F 3/1007 (2013.01); B22F 3/105 (2013.01); C22C 19/057 (2013.01); B22F 2009/043 (2013.01); B22F 2201/11 (2013.01); B22F 2301/155 (2013.01); B22F 2304/10 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A method for preparing a nickel-based superalloy formed by selective laser melting, comprising:
(1) ball milling and drying a nickel-based superalloy powder and a grain refiner in sequence to obtain a mixed powder,
the nickel-based superalloy powder comprising, percentages by mass, 18-19% of Fe, 52-53% of Ni, 19-20% of Cr, 3.0-3.5% of Mo, 0.2-0.3% of Al, 0.7-0.8% of Ti, 5.4-5.6% of Nb, 0.2-0.3% of Co, 0.01-0.02% of C, 0.04-0.05% of Mn, 0.1-0.2% of Si, 0.02-0.03% of Cu, not more than 0.0015% of S, and not more than 0.005% of B, and the grain refiner being a CrFeNb alloy powder; and
(2) selective laser melting the mixed powder obtained in act (1) to obtain the nickel-based superalloy,
wherein the CrFeNb alloy powder in act (1) comprises, in percentages by mass, 24-28% of Cr, 25-30% of Fe, and 45-50% of Nb;
the grain refiner in the mixed powder in act (1) accounts for 2 wt. %-4 wt. %;
the selective laser melting in act (2) is performed under conditions:
a laser power of 200-250 W, a scanning speed of 667-833 mm/s, and a layer thickness of 40-60 μm, a hatch distance of 50-90 μm, and a laser spot diameter of 75 μm; and
the method further comprises heating the nickel-based superalloy to a first temperature of 1050-1200° C. and maintaining at the first temperature for 1-2 hours, cooling in a furnace to a second temperature of 950-1000° C. and maintaining at the second temperature for 1-1.5 hours, and air-cooling to a third temperature of 700-750° C. and maintaining at the third temperature for 6-10 h; cooling to a fourth temperature of 600-650° C. at a rate of 50-60° C./h and maintaining at the fourth temperature for 6-10 h, and cooling in the furnace to room temperature.