Based on the deforming technique of severe plastic deformation(SPD), the grain refinement of a Mg-9Gd-3Y-2Zn-0.5Zr alloy treated with decreasing temperature reciprocating upsetting-extrusion(RUE) and its influence on ...Based on the deforming technique of severe plastic deformation(SPD), the grain refinement of a Mg-9Gd-3Y-2Zn-0.5Zr alloy treated with decreasing temperature reciprocating upsetting-extrusion(RUE) and its influence on the mechanical properties and wear behavior of the alloy were studied. The RUE process was carried out for 4 passes in total, starting at 0 ℃ and decreasing by 10 ℃ for each pass. The results showed that as the number of RUE passes increased, the grain refinement effect was obvious, and the second phase in the alloy was evenly distributed. Room temperature tensile properties of the alloy and the deepening of the RUE degree showed a positive correlation trend, which was due to the grain refinement, uniform distribution of the second phase and texture weakening. And the microhardness of the alloy showed that the microhardness of RUE is the largest in 2 passes. The change in microhardness was the result of dynamic competition between the softening effect of DRX and the work hardening effect. In addition, the wear resistance of the alloy showed a positive correlation with the degree of RUE under low load conditions. When the applied load was higher, the wear resistance of the alloy treated with RUE decreased compared to the initial state alloy. This phenomenon was mainly due to the presence of oxidative wear on the surface of the alloy, which could balance the positive contribution of severe plastic deformation to wear resistance to a certain extent.展开更多
采用人工拆解、高温处理以及浓硫酸与过氧化氢溶解等方式对钴锂离子电池电极材料进行分离及成分分析,考察了浓硫酸加入量、反应温度、时间对正极材料溶解率的影响。研究结果表明:当浓硫酸加入2 m L、控制反应温度70?C、反应时间40 min时...采用人工拆解、高温处理以及浓硫酸与过氧化氢溶解等方式对钴锂离子电池电极材料进行分离及成分分析,考察了浓硫酸加入量、反应温度、时间对正极材料溶解率的影响。研究结果表明:当浓硫酸加入2 m L、控制反应温度70?C、反应时间40 min时,正极材料能够在溶液中很好地溶解,溶解率最高可达92.1%。通过定量分析发现,该锂离子电池正极材料中钴的含量最大,质量分数可达29.52%。与铜钴硫化矿、含钴黄铁矿等矿石相比,该锂离子正极材料的钴丰度较高,极具回收价值。展开更多
基金financially supported by the Natural Science Foundation of Shanxi Province (No. 201901D111176)the Joint Funds of the National Natural Science Foundation of china (Grant No. U20A20230)+3 种基金the Bureau of science, technology and industry for National Defense of China (No. WDZC2019JJ006)the Key R&D program of Shanxi Province (International Cooperation) (No. 201903D421036)the National Natural Science Foundation of China (Grant No. 52075501)Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (No. 2018002)。
文摘Based on the deforming technique of severe plastic deformation(SPD), the grain refinement of a Mg-9Gd-3Y-2Zn-0.5Zr alloy treated with decreasing temperature reciprocating upsetting-extrusion(RUE) and its influence on the mechanical properties and wear behavior of the alloy were studied. The RUE process was carried out for 4 passes in total, starting at 0 ℃ and decreasing by 10 ℃ for each pass. The results showed that as the number of RUE passes increased, the grain refinement effect was obvious, and the second phase in the alloy was evenly distributed. Room temperature tensile properties of the alloy and the deepening of the RUE degree showed a positive correlation trend, which was due to the grain refinement, uniform distribution of the second phase and texture weakening. And the microhardness of the alloy showed that the microhardness of RUE is the largest in 2 passes. The change in microhardness was the result of dynamic competition between the softening effect of DRX and the work hardening effect. In addition, the wear resistance of the alloy showed a positive correlation with the degree of RUE under low load conditions. When the applied load was higher, the wear resistance of the alloy treated with RUE decreased compared to the initial state alloy. This phenomenon was mainly due to the presence of oxidative wear on the surface of the alloy, which could balance the positive contribution of severe plastic deformation to wear resistance to a certain extent.
文摘采用人工拆解、高温处理以及浓硫酸与过氧化氢溶解等方式对钴锂离子电池电极材料进行分离及成分分析,考察了浓硫酸加入量、反应温度、时间对正极材料溶解率的影响。研究结果表明:当浓硫酸加入2 m L、控制反应温度70?C、反应时间40 min时,正极材料能够在溶液中很好地溶解,溶解率最高可达92.1%。通过定量分析发现,该锂离子电池正极材料中钴的含量最大,质量分数可达29.52%。与铜钴硫化矿、含钴黄铁矿等矿石相比,该锂离子正极材料的钴丰度较高,极具回收价值。
