Nanocrystallized Al-10.0%Zn-3.0%Mg-1.8%Cu(mass fraction)alloy powder was prepared by cryomilling,and then the nanostructured powder was consolidated into bulk material by spark plasma sintering(SPS).The microstructura...Nanocrystallized Al-10.0%Zn-3.0%Mg-1.8%Cu(mass fraction)alloy powder was prepared by cryomilling,and then the nanostructured powder was consolidated into bulk material by spark plasma sintering(SPS).The microstructural evolution and phase transformation were studied.A supersaturated face-centered cubic solid solution is formed after cryomilling for 10 h,and the average grain size is 28 nm.Two typical nanostructures of the bulk nanostructured alloy are observed:primarily equiaxed grains with size of 150 nm,and occasionally occurring sub-micron grains up to 500 nm.Two types of MgZn2 particles precipitate during consolidation. One is the sub-micron particles distributed along the boundaries of the powders,and the other is fine particles with size of several nanometers in the matrix,especially at the boundaries of sub-micron grains.These second phase particles can be completely dissolved into matrix by proper solid solution treatment.展开更多
对净化前、后合金氢含量和力学性能进行测试,并采用TEM对等离子净化后的Al-Zn-Mg合金时效组织进行分析。结果表明:Al-Zn-Mg合金氢含量由0.17 mL/100 g Al降低到0.11 mL/100 g Al;经460℃×120 min固溶、130℃×16 h时效处理后,...对净化前、后合金氢含量和力学性能进行测试,并采用TEM对等离子净化后的Al-Zn-Mg合金时效组织进行分析。结果表明:Al-Zn-Mg合金氢含量由0.17 mL/100 g Al降低到0.11 mL/100 g Al;经460℃×120 min固溶、130℃×16 h时效处理后,晶内的析出相细小弥散,晶界上析出相连续分布,GP区起主要的强化作用;Rm达到590 MPa,Rp0.2达到510 MPa,断后伸长率达到8.5%,硬度达到160HB。展开更多
通过对混合Zn或者Dy_2O_3粉末的快淬Nd10.15Pr1.86Fe80.41Al1.67B5.91粉末进行放电等离子烧结(SPS),制备出各向同性Nd Fe B永磁材料,分别研究了两种粉末的添加对磁体组织形貌和性能的影响。结果表明,Zn可以起到细化磁体内部晶粒尺寸的作...通过对混合Zn或者Dy_2O_3粉末的快淬Nd10.15Pr1.86Fe80.41Al1.67B5.91粉末进行放电等离子烧结(SPS),制备出各向同性Nd Fe B永磁材料,分别研究了两种粉末的添加对磁体组织形貌和性能的影响。结果表明,Zn可以起到细化磁体内部晶粒尺寸的作用,并且会和主相反应生成Nd Zn及Nd Zn5相;Dy_2O_3不利于磁体的致密化,其磁性能的提高被认为是粉末对于磁体内部晶粒的细化作用以及(Nd,Dy)2Fe14B相形成共同作用的结果。对于添加Zn粉末磁体,当Zn添加量为0.6wt%时,磁体获得最佳磁性能;对于添加Dy_2O_3粉末磁体,当Dy_2O_3添加量为2.0wt%时,磁体获得最佳磁性能。展开更多
基金Project(2002AA302502)supported by the Hi-tech Research and Development Program of ChinaProject(20050008016)supported by the Research Fund for the Doctoral Program of Higher Education,China
文摘Nanocrystallized Al-10.0%Zn-3.0%Mg-1.8%Cu(mass fraction)alloy powder was prepared by cryomilling,and then the nanostructured powder was consolidated into bulk material by spark plasma sintering(SPS).The microstructural evolution and phase transformation were studied.A supersaturated face-centered cubic solid solution is formed after cryomilling for 10 h,and the average grain size is 28 nm.Two typical nanostructures of the bulk nanostructured alloy are observed:primarily equiaxed grains with size of 150 nm,and occasionally occurring sub-micron grains up to 500 nm.Two types of MgZn2 particles precipitate during consolidation. One is the sub-micron particles distributed along the boundaries of the powders,and the other is fine particles with size of several nanometers in the matrix,especially at the boundaries of sub-micron grains.These second phase particles can be completely dissolved into matrix by proper solid solution treatment.
基金National Natural Science Foundation of China(No.52161040)Major Science and Technology Research and Development Project of Jiangxi Province(No.20203ABC28W006)+1 种基金Natural Science Foundation of Jiangxi Province,China,(No.20202ACBL214011)Key Project of"Science and Technology to Promote Mongolian Development",China(No.XM2021BT03)。
文摘通过对混合Zn或者Dy_2O_3粉末的快淬Nd10.15Pr1.86Fe80.41Al1.67B5.91粉末进行放电等离子烧结(SPS),制备出各向同性Nd Fe B永磁材料,分别研究了两种粉末的添加对磁体组织形貌和性能的影响。结果表明,Zn可以起到细化磁体内部晶粒尺寸的作用,并且会和主相反应生成Nd Zn及Nd Zn5相;Dy_2O_3不利于磁体的致密化,其磁性能的提高被认为是粉末对于磁体内部晶粒的细化作用以及(Nd,Dy)2Fe14B相形成共同作用的结果。对于添加Zn粉末磁体,当Zn添加量为0.6wt%时,磁体获得最佳磁性能;对于添加Dy_2O_3粉末磁体,当Dy_2O_3添加量为2.0wt%时,磁体获得最佳磁性能。