Numerical simulation is one of the important auxiliary methods for studying materials-related problems. In this study, phase field simulation was employed to investigate the refinement behavior of BAg55CuZn-x B brazin...Numerical simulation is one of the important auxiliary methods for studying materials-related problems. In this study, phase field simulation was employed to investigate the refinement behavior of BAg55CuZn-x B brazing alloys. Simulation and experimental studies were conducted for B contents ranging from 0 wt.% to 0.2 wt.%. The results demonstrated that the addition of 0.05 wt.% B in the brazing alloy leads to a significant refinement effect. As the B content increases, the grain size further reduces, and a refinement stagnation phenomenon occurs after exceeding 0.15 wt.%. The solidification process of brazing alloys with different B content was predicted by simulation, and the simulation results showed that with the increase of B content, the initial number of nucleation increased, and the radius of the dendrite tip decreased. The simulation results are in good agreement with the experimental findings, providing further evidence of the refining effect of the B element and the reliable predictive capability of the phase field model.展开更多
High temperature in diffusion bonding(DB)process severely deteriorates the performance of zirconium(Zr)R60702 in extreme chemical environment.Therefore,it is important to reduce the DB temperature of Zr R60702.In this...High temperature in diffusion bonding(DB)process severely deteriorates the performance of zirconium(Zr)R60702 in extreme chemical environment.Therefore,it is important to reduce the DB temperature of Zr R60702.In this work,low-temperature diffusion bonding of Zr R60702 at 750°C is realized by 0.3 wt%hydrogen addition while 900°C is required in DB process for unhydrogenated Zr R60702.The shear strength of the hydrogenated joint bonded at 750°C reaches 388 MPa,which is 117.98%higher than that of the unhydrogenated joint bonded at 750°C and equal to that of the unhydrogenated joint bonded at 900°C.The effects of hydrogen addition in Zr R60702 on the microstructure evolution,phase transformation temperature,interatomic bonding and self-diffusion coefficient of Zr atoms are investigated in detail.The results show that the optimized DB properties can be attributed to the improvements of its grain boundary diffusion,plasticity and self-diffusion coefficient of Zr atoms.展开更多
基金the Major Science and Technology Project of Henan Province.(No.221100230300).
文摘Numerical simulation is one of the important auxiliary methods for studying materials-related problems. In this study, phase field simulation was employed to investigate the refinement behavior of BAg55CuZn-x B brazing alloys. Simulation and experimental studies were conducted for B contents ranging from 0 wt.% to 0.2 wt.%. The results demonstrated that the addition of 0.05 wt.% B in the brazing alloy leads to a significant refinement effect. As the B content increases, the grain size further reduces, and a refinement stagnation phenomenon occurs after exceeding 0.15 wt.%. The solidification process of brazing alloys with different B content was predicted by simulation, and the simulation results showed that with the increase of B content, the initial number of nucleation increased, and the radius of the dendrite tip decreased. The simulation results are in good agreement with the experimental findings, providing further evidence of the refining effect of the B element and the reliable predictive capability of the phase field model.
基金supported by the NSFC-Liaoning Province United Foundation(U1908229)the National Natural Science Foundation of China(51875350)the Program of Shanghai Academic Research Leader(22XD1421600).
文摘High temperature in diffusion bonding(DB)process severely deteriorates the performance of zirconium(Zr)R60702 in extreme chemical environment.Therefore,it is important to reduce the DB temperature of Zr R60702.In this work,low-temperature diffusion bonding of Zr R60702 at 750°C is realized by 0.3 wt%hydrogen addition while 900°C is required in DB process for unhydrogenated Zr R60702.The shear strength of the hydrogenated joint bonded at 750°C reaches 388 MPa,which is 117.98%higher than that of the unhydrogenated joint bonded at 750°C and equal to that of the unhydrogenated joint bonded at 900°C.The effects of hydrogen addition in Zr R60702 on the microstructure evolution,phase transformation temperature,interatomic bonding and self-diffusion coefficient of Zr atoms are investigated in detail.The results show that the optimized DB properties can be attributed to the improvements of its grain boundary diffusion,plasticity and self-diffusion coefficient of Zr atoms.
