The mechanical properties of Ti-23Al-17Nb (mole fraction,%) laser beam welding alloy joint at room temperature are comparable to that of the base materials.However,the strength and ductility of the as-welded joint det...The mechanical properties of Ti-23Al-17Nb (mole fraction,%) laser beam welding alloy joint at room temperature are comparable to that of the base materials.However,the strength and ductility of the as-welded joint deteriorate seriously after high temperature circulation.The effect of post-welded heat treatment on the microstructure and mechanical properties of the joint was investigated.The heat treatment was taken at 980 ℃ for 1.5 h,then furnace cooling and air cooling were performed separately.The results indicate that proper post-welded heat treatment improves the ductility of the joint at high temperature.展开更多
Microstructure and tensile properties of Ti-23Al-17Nb （at%） alloy sheets rolled in （a2 ＋ B2 ＋ O） phase field with the various heat treatments were studied. Before rolling the microstructure of the billet is B2 p...Microstructure and tensile properties of Ti-23Al-17Nb （at%） alloy sheets rolled in （a2 ＋ B2 ＋ O） phase field with the various heat treatments were studied. Before rolling the microstructure of the billet is B2 phase particles embedded in O phase continuity matrix. The B2 phases are deformed more greatly than a2/O phases during the same rolling step. The （a2 ＋B2） two phase equiaxed microstrueture can be obtained by solution treatment in （a2 ＋ B2） phase field. The B2 phases become the continuous matrix by recrystallization and growing up of B2 and thus anisotropy caused by rolling can be decreased. The microstructure obtained by solution treatment has better tensile properties than the microstructure gained by subsequent aging treatment in （O＋ B2） phase field because the O phases precipitate as the block structure during aging and results in the B2 matrix continuity being broken down.展开更多
文摘The mechanical properties of Ti-23Al-17Nb (mole fraction,%) laser beam welding alloy joint at room temperature are comparable to that of the base materials.However,the strength and ductility of the as-welded joint deteriorate seriously after high temperature circulation.The effect of post-welded heat treatment on the microstructure and mechanical properties of the joint was investigated.The heat treatment was taken at 980 ℃ for 1.5 h,then furnace cooling and air cooling were performed separately.The results indicate that proper post-welded heat treatment improves the ductility of the joint at high temperature.
文摘Microstructure and tensile properties of Ti-23Al-17Nb （at%） alloy sheets rolled in （a2 ＋ B2 ＋ O） phase field with the various heat treatments were studied. Before rolling the microstructure of the billet is B2 phase particles embedded in O phase continuity matrix. The B2 phases are deformed more greatly than a2/O phases during the same rolling step. The （a2 ＋B2） two phase equiaxed microstrueture can be obtained by solution treatment in （a2 ＋ B2） phase field. The B2 phases become the continuous matrix by recrystallization and growing up of B2 and thus anisotropy caused by rolling can be decreased. The microstructure obtained by solution treatment has better tensile properties than the microstructure gained by subsequent aging treatment in （O＋ B2） phase field because the O phases precipitate as the block structure during aging and results in the B2 matrix continuity being broken down.
