Effects of Rare Earth(Hereafter RE)on the conductance of high-purity and industrial-purity aluminum wires have been studied.RE increases the resistivity of the high-purity aluminum.No evidence has been found that RE w...Effects of Rare Earth(Hereafter RE)on the conductance of high-purity and industrial-purity aluminum wires have been studied.RE increases the resistivity of the high-purity aluminum.No evidence has been found that RE will decrease the resistivity of industrial-pure aluminum under various RE content including 0.3%Ce.The individual role of RE and its combined effects with Fe and Si have been discussed too.展开更多
The evolution of microstructure in the drawing process of commercially pure aluminum wire (CPAW) does not only depend on the nature of materials, but also on the stress profile. In this study, the effect of stress p...The evolution of microstructure in the drawing process of commercially pure aluminum wire (CPAW) does not only depend on the nature of materials, but also on the stress profile. In this study, the effect of stress profile on the texture evolution of the CPAW was systematically investigated by combining the numerical simulation and the microstructure observation. The results show that the tensile stress at the wire center promotes the formation of 〈111〉 texture, whereas the shear stress nearby the rim makes little contribution to the texture formation. Therefore, the 〈111 〉 texture at the wire center is stronger than that in the surface layer, which also results in a higher microhardness at the center of the CPAW under axial loading.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.展开更多
To study the evolution of nanoparticles during Al wire electrical explosion,a nanoparticle formation model that considered layered motion was developed,and an experimental system was set up to carry out electrical exp...To study the evolution of nanoparticles during Al wire electrical explosion,a nanoparticle formation model that considered layered motion was developed,and an experimental system was set up to carry out electrical explosion experiments using 0.1 mm and 0.2 mm Al wires.The characteristic parameters and evolution process during the formation of nanoparticles were calculated and analyzed.The results show that the maximum velocities of the innermost and outermost layers are about 1200 m·s-1and 1600 m·s-1,and the velocity of the middle layer is about 1400 m·s-1,respectively.Most of the nanoparticles are formed in the temperature range of2600 K-2500 K.The characteristic temperature for the formation of Al nanoparticles is~2520K,which is also the characteristic temperature of other parameters.The size distribution range of the formed nanoparticles is 18 to 110 nm,and most of them are around 22 nm.The variation of saturated vapor pressure determines the temperature distribution range of particle nucleation.There is a minimum critical diameter of particles(~25 nm);particles smaller than the critical diameter can grow into larger particles during surface growth.Particle motion has an effect on the surface growth and aggregation process of particles,and also on the distribution area of larger-diameter particles.The simulation results are in good agreement with the experiments.We provide a method to estimate the size and distribution of nanoparticles,which is of great significance to understand the formation process of particles during the evolution of wire electrical explosion.展开更多
The largest wire and cable production enterprise in the northwestern region-Qinghai Xingming Electric Power Material Co.,Ltd.has been officially put into production,meaning that Qinghai will be able to selfproduce med...The largest wire and cable production enterprise in the northwestern region-Qinghai Xingming Electric Power Material Co.,Ltd.has been officially put into production,meaning that Qinghai will be able to selfproduce medium and high voltage or even EHV crosslinked power cables and develop and produce differentiated new products such as high-altitude cold-resistant photovoltaic展开更多
In this study the process of cladding steel wires with aluminum is investigated experimentally. It is studied how the cladding process and the quality of products are influenced by the aluminum deformation temperature...In this study the process of cladding steel wires with aluminum is investigated experimentally. It is studied how the cladding process and the quality of products are influenced by the aluminum deformation temperature, the wheel speed, the temperature of steel wire, the wire speed and the steel wire tensile force. The relation among the process parameters above is discussed, and the effect of the aluminum deformation temperature on the coating microstructure is analyzed. This paper suggested a reasonable range of process parameters for producing aluminum cladding steel wires.展开更多
The weld appearance, deposition rate, welding efficiency, stability of arc, laser keyhole characteristic, and weld property were studied by using a novel laser-MIG hybrid welding process with filling wire of aluminum ...The weld appearance, deposition rate, welding efficiency, stability of arc, laser keyhole characteristic, and weld property were studied by using a novel laser-MIG hybrid welding process with filling wire of aluminum alloy. The results were also compared with those by conventional laser-MIG hybrid welding process. It was found that with the suitable process parameters this novel welding process for aluminum alloy was stable and final weld bead had fine appearance. Compared to conventional laser-MIG hybrid welding process, during this novel welding process the stability of arc, the laser keyhole characteristic and the weld property were similar, while the keyhole cycle frequency and keyhole opening area had differences of 1.23% and 15.34%, respectively, and the welding efficiency increased by about 31% without increasing heat input.展开更多
The force feed lubrication method is used for drawing aluminum clad steel wire. It is studied how deformation of wire and aspect of the lubricant film are influenced by the die angle, the reduction, the drawing spee...The force feed lubrication method is used for drawing aluminum clad steel wire. It is studied how deformation of wire and aspect of the lubricant film are influenced by the die angle, the reduction, the drawing speed and the gap between pressure die and wire. It has been concluded that when the factors above mentioned promote to thicken lubricant film, the drawing force is reduced and this favors the homogenous deformation of aluminum coating and steel core.展开更多
在冷金属过渡(cold metal transfer,CMT)电弧增材制造过程中,熔池的流动行为极易受到电弧和熔滴的影响,从而严重影响堆积层的稳定性和成形件质量.该文利用高速摄影结果及电信号参数波形图,引入热输入量计算公式,从特征电信号、熔滴过渡...在冷金属过渡(cold metal transfer,CMT)电弧增材制造过程中,熔池的流动行为极易受到电弧和熔滴的影响,从而严重影响堆积层的稳定性和成形件质量.该文利用高速摄影结果及电信号参数波形图,引入热输入量计算公式,从特征电信号、熔滴过渡特征量、热输入量等方面定量分析了CMT+P模式下送丝速度及脉冲修正系数对熔滴过渡过程及单道成形形貌的影响,同时分析了脉冲变极性冷金属过渡(Advanced CMT,CMT+PA)模式下送丝速度及控制面板上的EP/EN修正系数η对熔滴过渡过程及单道成形形貌的影响,为后续工艺优化提供参考和指导.展开更多
Eleven groups of wire bonding experiments are carried out on an experiment platform (restructured with a U3000 heavy aluminum wedge wire bonder). Pure silicon aluminum wire (300 μm in diameter, 2.94-3.92 N in aver...Eleven groups of wire bonding experiments are carried out on an experiment platform (restructured with a U3000 heavy aluminum wedge wire bonder). Pure silicon aluminum wire (300 μm in diameter, 2.94-3.92 N in average pull force) and nickel coated aluminum substrates are used in the experiments. During the experiment process, only ultrasonic power rate parameter is changed and the other bonding parameters are kept as constant, The bonding force and time are 4.90 N and 100 ms respectively. After the bonding experiments, shear strength tests are carried out on the bonds as the bonding strength criterion. From those experiments and test results, some conclusions are obtained: In the small ultrasonic power rate conditions (about 20%-30%), with the power increasing, the bonding strength enhances accordingly; However, in the large ultrasonic power rate conditions (about 45%-70%), the bonding strength decreases accordingly and over bonding happens. Only when the ultrasonic power rate is in a moderate condition (about 35%-40%) can good and stabilized bonding strength be acquired.展开更多
为严格控制铝合金焊丝内在氢含量,分析了铝合金焊丝冶炼过程中充氩工艺参数对合金熔体及固体氢含量的影响,并比较了熔体测氢与固体测氢方法的异同。结果表明,2~4吨铝熔体冶炼过程中,减小精炼氩气的流量可以显著减少合金熔体减压凝固测...为严格控制铝合金焊丝内在氢含量,分析了铝合金焊丝冶炼过程中充氩工艺参数对合金熔体及固体氢含量的影响,并比较了熔体测氢与固体测氢方法的异同。结果表明,2~4吨铝熔体冶炼过程中,减小精炼氩气的流量可以显著减少合金熔体减压凝固测氢试样纵切面上的气孔数量和尺寸,降低熔体的氢含量,当充氩流量为8~10 mL/min时,熔体除氢效果达到最佳;固体测氢方法可以准确提取固体焊丝中的真实氢含量(单位:ppm),经过计算1 mL/100 g Al等价于0.899 ppm,当氩气流量控制在8~10 mL/min时固体焊丝合金中的氢含量为0.17~0.18 mL/100 g Al,可满足低氢焊丝生产要求;同等充氩工艺条件下,固体测氢值高于熔体测氢值,二者比值保持在1.7~2.1之间,固体测氢与熔体测氢各有优劣,二者可以互为补充、配合使用。展开更多
文摘Effects of Rare Earth(Hereafter RE)on the conductance of high-purity and industrial-purity aluminum wires have been studied.RE increases the resistivity of the high-purity aluminum.No evidence has been found that RE will decrease the resistivity of industrial-pure aluminum under various RE content including 0.3%Ce.The individual role of RE and its combined effects with Fe and Si have been discussed too.
基金financially supported by the State Grid Corporation of China (No. 52110416001z)the National Natural Science Foundation of China (No. 51331007)
文摘The evolution of microstructure in the drawing process of commercially pure aluminum wire (CPAW) does not only depend on the nature of materials, but also on the stress profile. In this study, the effect of stress profile on the texture evolution of the CPAW was systematically investigated by combining the numerical simulation and the microstructure observation. The results show that the tensile stress at the wire center promotes the formation of 〈111〉 texture, whereas the shear stress nearby the rim makes little contribution to the texture formation. Therefore, the 〈111 〉 texture at the wire center is stronger than that in the surface layer, which also results in a higher microhardness at the center of the CPAW under axial loading.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
文摘To study the evolution of nanoparticles during Al wire electrical explosion,a nanoparticle formation model that considered layered motion was developed,and an experimental system was set up to carry out electrical explosion experiments using 0.1 mm and 0.2 mm Al wires.The characteristic parameters and evolution process during the formation of nanoparticles were calculated and analyzed.The results show that the maximum velocities of the innermost and outermost layers are about 1200 m·s-1and 1600 m·s-1,and the velocity of the middle layer is about 1400 m·s-1,respectively.Most of the nanoparticles are formed in the temperature range of2600 K-2500 K.The characteristic temperature for the formation of Al nanoparticles is~2520K,which is also the characteristic temperature of other parameters.The size distribution range of the formed nanoparticles is 18 to 110 nm,and most of them are around 22 nm.The variation of saturated vapor pressure determines the temperature distribution range of particle nucleation.There is a minimum critical diameter of particles(~25 nm);particles smaller than the critical diameter can grow into larger particles during surface growth.Particle motion has an effect on the surface growth and aggregation process of particles,and also on the distribution area of larger-diameter particles.The simulation results are in good agreement with the experiments.We provide a method to estimate the size and distribution of nanoparticles,which is of great significance to understand the formation process of particles during the evolution of wire electrical explosion.
文摘The largest wire and cable production enterprise in the northwestern region-Qinghai Xingming Electric Power Material Co.,Ltd.has been officially put into production,meaning that Qinghai will be able to selfproduce medium and high voltage or even EHV crosslinked power cables and develop and produce differentiated new products such as high-altitude cold-resistant photovoltaic
文摘In this study the process of cladding steel wires with aluminum is investigated experimentally. It is studied how the cladding process and the quality of products are influenced by the aluminum deformation temperature, the wheel speed, the temperature of steel wire, the wire speed and the steel wire tensile force. The relation among the process parameters above is discussed, and the effect of the aluminum deformation temperature on the coating microstructure is analyzed. This paper suggested a reasonable range of process parameters for producing aluminum cladding steel wires.
基金supported by the Key Science and Technology of Jilin Province(Grant No.20140204070GX)
文摘The weld appearance, deposition rate, welding efficiency, stability of arc, laser keyhole characteristic, and weld property were studied by using a novel laser-MIG hybrid welding process with filling wire of aluminum alloy. The results were also compared with those by conventional laser-MIG hybrid welding process. It was found that with the suitable process parameters this novel welding process for aluminum alloy was stable and final weld bead had fine appearance. Compared to conventional laser-MIG hybrid welding process, during this novel welding process the stability of arc, the laser keyhole characteristic and the weld property were similar, while the keyhole cycle frequency and keyhole opening area had differences of 1.23% and 15.34%, respectively, and the welding efficiency increased by about 31% without increasing heat input.
文摘The force feed lubrication method is used for drawing aluminum clad steel wire. It is studied how deformation of wire and aspect of the lubricant film are influenced by the die angle, the reduction, the drawing speed and the gap between pressure die and wire. It has been concluded that when the factors above mentioned promote to thicken lubricant film, the drawing force is reduced and this favors the homogenous deformation of aluminum coating and steel core.
基金Acknowledgement The authors would like to appreciate the financial support from the National Natural Science Foundation of China (Grant No. 50874033 ).
文摘在冷金属过渡(cold metal transfer,CMT)电弧增材制造过程中,熔池的流动行为极易受到电弧和熔滴的影响,从而严重影响堆积层的稳定性和成形件质量.该文利用高速摄影结果及电信号参数波形图,引入热输入量计算公式,从特征电信号、熔滴过渡特征量、热输入量等方面定量分析了CMT+P模式下送丝速度及脉冲修正系数对熔滴过渡过程及单道成形形貌的影响,同时分析了脉冲变极性冷金属过渡(Advanced CMT,CMT+PA)模式下送丝速度及控制面板上的EP/EN修正系数η对熔滴过渡过程及单道成形形貌的影响,为后续工艺优化提供参考和指导.
基金This project is supported by National Natural Science Foundation of China (No.50390064)National Basic Research Program of China(973 Program,No.2003CB716202).
文摘Eleven groups of wire bonding experiments are carried out on an experiment platform (restructured with a U3000 heavy aluminum wedge wire bonder). Pure silicon aluminum wire (300 μm in diameter, 2.94-3.92 N in average pull force) and nickel coated aluminum substrates are used in the experiments. During the experiment process, only ultrasonic power rate parameter is changed and the other bonding parameters are kept as constant, The bonding force and time are 4.90 N and 100 ms respectively. After the bonding experiments, shear strength tests are carried out on the bonds as the bonding strength criterion. From those experiments and test results, some conclusions are obtained: In the small ultrasonic power rate conditions (about 20%-30%), with the power increasing, the bonding strength enhances accordingly; However, in the large ultrasonic power rate conditions (about 45%-70%), the bonding strength decreases accordingly and over bonding happens. Only when the ultrasonic power rate is in a moderate condition (about 35%-40%) can good and stabilized bonding strength be acquired.
基金supported by the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(No.KYCX22_1311)the Natural Science Foundation of Jiangsu Province,China(No.BK20190684)the Natural Science Research of the Jiangsu Higher Education Institutions of China(No.18KJB460016)。
文摘为严格控制铝合金焊丝内在氢含量,分析了铝合金焊丝冶炼过程中充氩工艺参数对合金熔体及固体氢含量的影响,并比较了熔体测氢与固体测氢方法的异同。结果表明,2~4吨铝熔体冶炼过程中,减小精炼氩气的流量可以显著减少合金熔体减压凝固测氢试样纵切面上的气孔数量和尺寸,降低熔体的氢含量,当充氩流量为8~10 mL/min时,熔体除氢效果达到最佳;固体测氢方法可以准确提取固体焊丝中的真实氢含量(单位:ppm),经过计算1 mL/100 g Al等价于0.899 ppm,当氩气流量控制在8~10 mL/min时固体焊丝合金中的氢含量为0.17~0.18 mL/100 g Al,可满足低氢焊丝生产要求;同等充氩工艺条件下,固体测氢值高于熔体测氢值,二者比值保持在1.7~2.1之间,固体测氢与熔体测氢各有优劣,二者可以互为补充、配合使用。