The high-throughput diffusion-multiple technique and thermodynamics databases were used to design new high-strength Ti alloys. The composition–microstructure–property relationships of the Ti64–xMo alloys were obtai...The high-throughput diffusion-multiple technique and thermodynamics databases were used to design new high-strength Ti alloys. The composition–microstructure–property relationships of the Ti64–xMo alloys were obtained. The phase fraction and composition of the α and β phases of the Ti64–xMo alloys were calculated using the Thermo-Calc software. After aging at 600℃, the Ti64–6 Mo alloy precipitated ultrafine α phases. This phenomenon was explained on the basis of the pseudo-spinodal mechanism by calculating the Gibbs energy curves of the α and β phases of the Ti64–xMo alloys at 600℃. Bulk forged Ti64–6 Mo alloy exhibited high strength and moderate plasticity after α/β-phase-field solution treatment plus aging. The tensile properties of the alloy were determined by the size and morphology of the primary and secondary α phases and by the β grain size.展开更多
The main reason for the high strength in near-βtitanium alloys is the ultrafine precipitation of the acicular secondary a phase in theβmatrix.The purpose of this study is to use the pseudo-spinodal mechanism to obta...The main reason for the high strength in near-βtitanium alloys is the ultrafine precipitation of the acicular secondary a phase in theβmatrix.The purpose of this study is to use the pseudo-spinodal mechanism to obtain the ultrafine a phase for the design of a new high-strength near-γtitanium alloy.Thermodynamic calculations and TC21-(TC21+15 Mo)diffusion couple composition gradient experiments were used to demonstrate that TC21+3 Mo alloy can undergo a pseudo-spinodal decomposition to obtain the ultrafine a phase,resulting in a high-strength alloy.By adjusting the heat treatment process to obtain a bimodal microstructure,the alloy exhibits a good balance between ultimate tensile strength(1351 MPa)and plasticity(8.5%strain).Thus,it was demonstrated that the pseudospinodal mechanism combined with a high-throughput diffusion couple technique is an effective method for designing high-strength titanium alloys.展开更多
基金financial support from the National Key Technologies R&D Program of China (Grant No. 2016YFB0701301 and 2018YFB0704100)National Natural Science Foundation of China (Grant No. 51671218 and 51501229)+1 种基金National Key Basic Research Program of China (973 Program) (Grant No. 2014CB644000)State Key Laboratory of Powder Metallurgy, Central South University, Changsha, China
文摘The high-throughput diffusion-multiple technique and thermodynamics databases were used to design new high-strength Ti alloys. The composition–microstructure–property relationships of the Ti64–xMo alloys were obtained. The phase fraction and composition of the α and β phases of the Ti64–xMo alloys were calculated using the Thermo-Calc software. After aging at 600℃, the Ti64–6 Mo alloy precipitated ultrafine α phases. This phenomenon was explained on the basis of the pseudo-spinodal mechanism by calculating the Gibbs energy curves of the α and β phases of the Ti64–xMo alloys at 600℃. Bulk forged Ti64–6 Mo alloy exhibited high strength and moderate plasticity after α/β-phase-field solution treatment plus aging. The tensile properties of the alloy were determined by the size and morphology of the primary and secondary α phases and by the β grain size.
基金financially supported by the National Key Technologies R&D Program of China(No.2016YFB0701301)the National Natural Science Foundation of China(Nos.51901251,51671218 and 51501229)the State Key Laboratory of Powder Metallurgy Independent Project of China(No.621021907)。
文摘The main reason for the high strength in near-βtitanium alloys is the ultrafine precipitation of the acicular secondary a phase in theβmatrix.The purpose of this study is to use the pseudo-spinodal mechanism to obtain the ultrafine a phase for the design of a new high-strength near-γtitanium alloy.Thermodynamic calculations and TC21-(TC21+15 Mo)diffusion couple composition gradient experiments were used to demonstrate that TC21+3 Mo alloy can undergo a pseudo-spinodal decomposition to obtain the ultrafine a phase,resulting in a high-strength alloy.By adjusting the heat treatment process to obtain a bimodal microstructure,the alloy exhibits a good balance between ultimate tensile strength(1351 MPa)and plasticity(8.5%strain).Thus,it was demonstrated that the pseudospinodal mechanism combined with a high-throughput diffusion couple technique is an effective method for designing high-strength titanium alloys.
