Microstructure and properties after deformation and aging process of A286 superalloy

• Published in: Rare metals 2019-09, Vol.38 (9), p.864-870
• Main Authors: Liu, Si-Cheng, Gao, Yun, Lin, Zhong-Liang, Guo, Shuang-Shuang, Zhang, Xiao-Bin, Yin, Xiao-Jian
• Format: Article
• Language: English
• Subjects: Aging; Aging (metallurgy); Aging (natural); Biomaterials; Carbides; Chemical precipitation; Chemistry and Materials Science; Cold drawing; Configurations; Crystal lattices; Deformation; Deformation effects; Edge dislocations; Emission analysis; Energy; Field emission microscopy; Gamma-prime phase (crystals); Grain boundaries; Grain size; Materials Engineering; Materials Science; Mechanical tests; Metallic Materials; Microscopy; Misalignment; Nanoscale Science and Technology; Optical microscopy; Physical Chemistry; Precipitates; Scanning electron microscopy; Solid solutions; Superalloys; Tempering; Tensile strength
• ISSN: 1001-0521; 1867-7185
• DOI: 10.1007/s12598-018-1171-2

This study focuses on the effects of different cold-drawing deformations and aging treatments of solid solution A286 superalloy. The grain configuration, texture, precipitates and tensile strength of A286 superalloy after different deformations and aging treatments were investigated by optical microscopy (OM), field emission scanning electron microscopy (FESEM), electron back-scattered diffraction (EBSD) and mechanical testing machine. The grain size and configuration of A286 alloy can hardly be changed during aging process. The initially equiaxial and twinned crystals are obvious when deformation is less than 30%, while the grain boundaries become blurry and slip bands appear after 35% deformation or more. γ′ phase and Cr-rich carbide are the precipitates of A286 alloy. For each deformation, γ′ phase plays a major role during aging and its amount increases gradually when the aging temperature changes from 650 to 680 °C, and a maximum tensile strength appears when following two-stage aging. With deformation increasing, the amounts of γ′ phase and Cr-rich carbide increase in varying degrees. Meanwhile, the wire textures become more obvious, the tensile strength is enhanced and the kernel average misorientation (KAM) increases gradually; the higher KAM of crystal lattices diffuses from the grain boundary to the matrix gradually.