Allvac 718Plus高温合金第二相演变与性能研究进展

唐丽婷, 郭倩颖, 李冲, 丁然, 刘永长

Advances in Secondary Phase Evolution and Performance Enhancement of Allvac 718Plus Superalloy

TANG Liting, GUO Qianying, LI Chong, DING Ran, LIU Yongchang

表1 Allvac 718Plus高温合金主要相的晶体结构及组成[4,18~22]

Table 1 Crystal structures and compositions of main phases in Allvac 718Plus alloy[4,18-22]

Phase Formula Crystal structure Lattice constant (a, b, c) γ - fcc (A1) a = 0.377 nm γ′ Ni3(Al, Ti) fcc (L12) a = 0.379 nm γ″ Ni3Nb bct (D022) a = 0.391 nm (c / a = 1.99) η Ni3Nb0.5(Ti, Al)0.5 Hexagonal (D024) a = 0.512 nm, c = 0.836 nm δ Ni3Nb Orthogonal (D0a) a = 0.514 nm, b = 0.423 nm, c = 0.453 nm MX (Nb, Ti)(C, N) fcc (B1) a = 0.443-0.444 nm C14 Laves (Ni, Cr, Fe)2(Nb, Mo, Ti) Hexagonal (D024) a = 0.88 nm, c = 0.45 nm σ (Fe, Ni)Cr Tetragonal (D4h14) a = 0.49 nm, c = 0.78 nm