Influence of Post-Treatment Process on Microstructure and Properties of Laser Additively Manufactured Nickel-Based Superalloy

后处理工艺对一种激光增材制造镍基高温合金组织与性能的影响

Defects such as cracks and micropores exist in nickel-based superalloy during laser powder bed fusion(LPBF),hindering their application in various fields.Hot isostatic pressing(HIP)was combined with conventional heat treatment(HT)to obtain LPBF nickel-based superalloy parts with ideal properties and fewer defects.The results show that HIP process can improve the densification,while the conventional HT can eliminate the micro-defects to improve the mechanical properties.After HIP treatment,the defect volume fraction of LPBF specimens decreases.After HT,the defect content of HIP+HT specimens increases slightly.After post-treatment,the hardness shows a decreasing trend,and the tensile strength and post-break elongation of HIP+HT specimens increase to 1326 MPa and 21.3%,respectively,at room temperature.

在激光增材制造过程中,镍基高温合金存在裂纹和微孔等缺陷,阻碍其在各领域应用。将热等静压(HIP)与传统热处理(HT)相结合,以获得缺陷少且性能理想的激光粉末床熔融(LPBF)镍基高温合金零件。结果表明,HIP工艺提高致密度,传统HT改善显微缺陷并提高力学性能。经HIP处理后,LPBF试样缺陷体积分数下降,经HT处理后,HIP+HT缺陷含量略有上升。经后处理后,硬度呈下降趋势,室温下,HIP+HT试样的抗拉伸强度和断后伸长率分别提高到1326 MPa和21.3%。