Based on thermodynamic calculations and continuous rheological extrusion(CRE)technology,Al-Ti-V-B master alloys were designed and prepared.The morphology and the distribution of the refined phases in the master alloys...Based on thermodynamic calculations and continuous rheological extrusion(CRE)technology,Al-Ti-V-B master alloys were designed and prepared.The morphology and the distribution of the refined phases in the master alloys were analyzed by XRD,SEM,and TEM.The effects of master alloy addition and holding time on the microstructure and mechanical properties of A356 alloy were investigated.Under the optimum refiner addition of 0.3wt.%and the holding time of 20 min,the average grain size of the refined A356 alloy is 151.8±9.11μm,89.62%lower than that of original A356 alloy.The tensile strength and elongation of as-cast A356refined alloy are 196.11 MPa and 5.75%,respectively.After T6 treatment,the tensile strength and elongation of A356 refined alloy are 290.1 MPa and 3.09%,respectively.The fracture morphology is characterized by a predominance of along-crystal fracture with a small amount of through-crystal fracture,attributed to the refined grains.Finer grains promote crack path deflection and localized plastic deformation,enhancing energy dissipation and reducing the tendency for brittle fracture.This study provides a novel approach to improving the mechanical properties of A356 alloy through grain refinement using CRE Al-Ti-V-B master alloy.展开更多
On the basis of Al-V-B grain refining agent,rare earth element La was added,and Al-5V-3B-0.5La intermediate alloy was prepared by sintering method.The size,distribution,and morphology of nucleation particles in the re...On the basis of Al-V-B grain refining agent,rare earth element La was added,and Al-5V-3B-0.5La intermediate alloy was prepared by sintering method.The size,distribution,and morphology of nucleation particles in the refining agent at different sintering temperatures and the refining effect on A356 alloy were studied.The experimental results show that with the increase of sintering temperature,the addition of La element reduces the particle size of nucleated particles in the refining agent,makes the distribution more uniform,and has a good grain refinement effect on A356 alloy,with a significant reduction in grain size to around 184.62μm.It provides reference for the development of high-quality grain refining agents.展开更多
基金supported by the National Key Research and Development Program of China (Grant No.2022YFB3706801)the National Natural Science Foundation of China (Grant Nos.U2341253,52371019,U2241232)+2 种基金the Dalian High-level Talents Innovation Support Program (Grant No.2021RD06)the Applied Basic Research Program of Liaoning Province (Grant No.2022JH2/101300003)the Natural Science Foundation of Liaoning Province (Grant Nos.2022-BS-262,JYTMS20230031)。
文摘Based on thermodynamic calculations and continuous rheological extrusion(CRE)technology,Al-Ti-V-B master alloys were designed and prepared.The morphology and the distribution of the refined phases in the master alloys were analyzed by XRD,SEM,and TEM.The effects of master alloy addition and holding time on the microstructure and mechanical properties of A356 alloy were investigated.Under the optimum refiner addition of 0.3wt.%and the holding time of 20 min,the average grain size of the refined A356 alloy is 151.8±9.11μm,89.62%lower than that of original A356 alloy.The tensile strength and elongation of as-cast A356refined alloy are 196.11 MPa and 5.75%,respectively.After T6 treatment,the tensile strength and elongation of A356 refined alloy are 290.1 MPa and 3.09%,respectively.The fracture morphology is characterized by a predominance of along-crystal fracture with a small amount of through-crystal fracture,attributed to the refined grains.Finer grains promote crack path deflection and localized plastic deformation,enhancing energy dissipation and reducing the tendency for brittle fracture.This study provides a novel approach to improving the mechanical properties of A356 alloy through grain refinement using CRE Al-Ti-V-B master alloy.
基金Funded by the Science and Technology Project of State Grid Shanghai Municipal Electric Power Company(No.5209A6240003)the 2024 Shanxi Provincial Major Science and Technology Special Project(No.202401050201003)。
文摘On the basis of Al-V-B grain refining agent,rare earth element La was added,and Al-5V-3B-0.5La intermediate alloy was prepared by sintering method.The size,distribution,and morphology of nucleation particles in the refining agent at different sintering temperatures and the refining effect on A356 alloy were studied.The experimental results show that with the increase of sintering temperature,the addition of La element reduces the particle size of nucleated particles in the refining agent,makes the distribution more uniform,and has a good grain refinement effect on A356 alloy,with a significant reduction in grain size to around 184.62μm.It provides reference for the development of high-quality grain refining agents.
