Design and Development of Novel Ni-based Superalloys for Additive Manufacturing

Author of the article:XIONG Qiang , LIAN Lixian , HU Wang , BAO Ziming , GAO Zhenhuan, ZHANG Yu , LIU Ying

Author's Workplace： College of Materials Science and Engineering, School of Computer Science and Engineering, State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment

Key Words： Ni-based superalloy; machine learning; component design; additive manufacturing; anti-cracking performance

Abstract： To meet the design demand for composition optimization of Ni-based superalloys for additive manufacturing, a novel Ni-based superalloy was developed by an integrated design strategy combining machine learning (ML) and anti-cracking factor screening. Thermodynamic calculations show that the alloy possesses a narrow solidification temperature range. Meanwhile, the alloy solidifies rapidly in the critical temperature interval with small total shrinkage strain and maximum strain rate, showing good solidification characteristics overall. The novel alloy was prepared by using the selective laser melting technique. No obvious cracks are observed in the longitudinal and cross-sectional metallography of the formed specimens, which shows good anti-cracking properties. Through optimization of the heat treatment process, the γ′ phase fraction of the alloy reaches 44.6% after aging at 900 ℃, without any TCP phase precipitation in the structure. The novel alloy developed in this paper achieves a balance between the crack resistance and mechanical properties of Ni-based superalloys in additive manufacturing. The comprehensive design strategy can provide new ideas for the rapid development of novel materials in the field of additive manufacturing.