Microstructure and mechanical property of MIM 418 superalloy

• Published in: Rare metals 2018-01, Vol.37 (1), p.35-39
• Main Authors: Yang, Fu-Bao, Jing, Yan-Hong, Li, Dan, Zhang, Lin, Li, Da-Quan, Zhu, Qiang
• Format: Article
• Language: English
• Subjects: Alloys; Biomaterials; Chemistry and Materials Science; Crystal defects; Electron microscopy; Elongation; Energy; Heat treating; Hot isostatic pressing; Injection molding; Materials Engineering; Materials Science; Mechanical properties; Metallic Materials; Microstructure; Molding (process); Nanoscale Science and Technology; Physical Chemistry; Sintering (powder metallurgy); Solution heat treatment; Superalloys; X-ray diffraction; 微观结构; 机械性质; MIM; 合金粉末; 扫描电子; 相对密度; K418; 注射塑
• ISSN: 1001-0521; 1867-7185
• DOI: 10.1007/s12598-014-0419-8

In this study, the influence of hot isostatic pressing（HIP） process on the 418 alloy produced by metal injection molding（MIM） technique（named as MIM 418）was investigated based on the characteristic analysis of 418 alloy powder. And comparison analysis of the microstructure and mechanical property between the MIM 418 and as-cast 418 alloys was performed by scanning electron microscopy（SEM）, energy-dispersive spectroscopy（EDS）,and X-ray diffraction（XRD）. The results show that MIM418 alloy exhibits fine grain（~30 μm） and uniform microstructure. The defects existing in MIM 418 alloy formed during sintering process can be eliminated through HIP treatment, and the relative density increases from97.0 % to 99.5 %. The mechanical property can be improved significantly because of the elimination of defects, and the tensile strength and elongation are1,271 MPa and 16.8 %, respectively, which are increased by 34.5 % and 180 % compared with K418 alloy after solution heat treatment.