CuCrZr alloys were treated with the thermal stretch process at various temperatures from 100 to 300℃.The results reveal that the thermal stretch process is successfully developed to manufacture the precipitation hard...CuCrZr alloys were treated with the thermal stretch process at various temperatures from 100 to 300℃.The results reveal that the thermal stretch process is successfully developed to manufacture the precipitation hardening CuCrZr alloys with a good combination of microhardness and electrical conductivity.By increasing the tensile elongations at each temperature from 100 to 300℃,the microhardness increases whereas the electrical conductivity decreases slightly.Cr-containing precipitate phases with a Nishiyama-Wasserman orientation relationship to the copper matrix were observed by TEM.The achievement of high micro-hardness and acceptable electrical conductivity in the thermal stretch treated alloys is ascribed to the interactions of the heteroatom solution,dislocation increment,grain refinement and dispersive precipitation effect.展开更多
The mixed nanostructure mainly consisting of nanotwins and nanograins was obtained in a solid solution CuCrZr alloy by means of dynamic plastic deformation at cryogenic temperature.After subsequent aging treatments,th...The mixed nanostructure mainly consisting of nanotwins and nanograins was obtained in a solid solution CuCrZr alloy by means of dynamic plastic deformation at cryogenic temperature.After subsequent aging treatments,the precipitation of Cr at nanometer scale provided further strengthening and brought substantial recovery of electrical conductivity.The aged nanostructured CuCrZr alloy exhibited a high tensile strength of 832MPa and a high electrical conductivity of 71.2%IACS.The details of precipitation tuned by nanotwin boundaries were demonstrated in this work.The combined strengthening of nanostructures and nanoprecipitates was discussed.展开更多
The application of Pr-Nd-Dy alloy in the field of high-performance Nd-Fe-B permanent magnet materials has great potential.The composition of the PrF_(3)-NdF_(3)-DyF_(3)-LiF(PND-LiF) electrolyte system used in the prod...The application of Pr-Nd-Dy alloy in the field of high-performance Nd-Fe-B permanent magnet materials has great potential.The composition of the PrF_(3)-NdF_(3)-DyF_(3)-LiF(PND-LiF) electrolyte system used in the production of Pr-Nd-Dy alloys,the distribution of F,Li,RE and other elements in the electrolyte and their occurrence state were studied in this paper.The effect of temperature and lithium fluoride addition on electrolyte conductivity was revealed using the continuous conductivity cell constant(CVCC) method.The thermal analysis method was used to study the influence of lithium fluoride addition on the electrolyte’s liquidus temperature and the optimal process conditions for the production of Pr-Nd-Dy alloy were determined.The results show that the overall distribution of praseodymium neodymium fluoride and lithium fluoride is uniform in the electrolyte and dysprosium fluoride is distributed between praseodymium-neodymium fluoride and lithium fluoride.Praseodymium-neodymium oxide is embedded in praseodymium neodymium fluoride in spotty pattern.The electrolyte’s conductivity is increased as the temperature and lithium fluoride addition are going up,while the liquidus temperature is going down with increasing lithium fluoride addition.The best electrolysis process conditions for the PND-LiF system to produce praseodymium neodymium dysprosium alloy are as follows:temperature1050℃ and 15.56 wt% PrF_(3)-62.22 wt% NdF_(3)-11.11 wt% DyF_(3)-11.11 wt% LiF.展开更多
基金Project(U1034002)supported by the National Natural Science Foundation of China(NSFC)-Guangdong Natural Science Mutual Funds
文摘CuCrZr alloys were treated with the thermal stretch process at various temperatures from 100 to 300℃.The results reveal that the thermal stretch process is successfully developed to manufacture the precipitation hardening CuCrZr alloys with a good combination of microhardness and electrical conductivity.By increasing the tensile elongations at each temperature from 100 to 300℃,the microhardness increases whereas the electrical conductivity decreases slightly.Cr-containing precipitate phases with a Nishiyama-Wasserman orientation relationship to the copper matrix were observed by TEM.The achievement of high micro-hardness and acceptable electrical conductivity in the thermal stretch treated alloys is ascribed to the interactions of the heteroatom solution,dislocation increment,grain refinement and dispersive precipitation effect.
基金supported by the Ministry of Science&Technology of China(No.2017YFA0204401)the Chinese Academy of Sciences(No.zdyz201701)+3 种基金the Liaoning Revitalization Talents Program(No.XLYC1808008)the National Natural Science Foundation of China(Nos.51501192 and 51771196)the Fundamental Research Funds for the Central Universities(No.3072019CF1017)the Key Research Program of Frontier Science,Chinese Academy of Sciences.
文摘The mixed nanostructure mainly consisting of nanotwins and nanograins was obtained in a solid solution CuCrZr alloy by means of dynamic plastic deformation at cryogenic temperature.After subsequent aging treatments,the precipitation of Cr at nanometer scale provided further strengthening and brought substantial recovery of electrical conductivity.The aged nanostructured CuCrZr alloy exhibited a high tensile strength of 832MPa and a high electrical conductivity of 71.2%IACS.The details of precipitation tuned by nanotwin boundaries were demonstrated in this work.The combined strengthening of nanostructures and nanoprecipitates was discussed.
基金Project supported by the National Key Research and Development Program of China(2019YFC1908403)。
文摘The application of Pr-Nd-Dy alloy in the field of high-performance Nd-Fe-B permanent magnet materials has great potential.The composition of the PrF_(3)-NdF_(3)-DyF_(3)-LiF(PND-LiF) electrolyte system used in the production of Pr-Nd-Dy alloys,the distribution of F,Li,RE and other elements in the electrolyte and their occurrence state were studied in this paper.The effect of temperature and lithium fluoride addition on electrolyte conductivity was revealed using the continuous conductivity cell constant(CVCC) method.The thermal analysis method was used to study the influence of lithium fluoride addition on the electrolyte’s liquidus temperature and the optimal process conditions for the production of Pr-Nd-Dy alloy were determined.The results show that the overall distribution of praseodymium neodymium fluoride and lithium fluoride is uniform in the electrolyte and dysprosium fluoride is distributed between praseodymium-neodymium fluoride and lithium fluoride.Praseodymium-neodymium oxide is embedded in praseodymium neodymium fluoride in spotty pattern.The electrolyte’s conductivity is increased as the temperature and lithium fluoride addition are going up,while the liquidus temperature is going down with increasing lithium fluoride addition.The best electrolysis process conditions for the PND-LiF system to produce praseodymium neodymium dysprosium alloy are as follows:temperature1050℃ and 15.56 wt% PrF_(3)-62.22 wt% NdF_(3)-11.11 wt% DyF_(3)-11.11 wt% LiF.
