A three-dimensional finite-element model of slab continuous casting mold was conducted to clarify the effect of cooling structure on thermal behavior of copper plates. The results show that temperature distribution of...A three-dimensional finite-element model of slab continuous casting mold was conducted to clarify the effect of cooling structure on thermal behavior of copper plates. The results show that temperature distribution of hot surface is mainly governed by cooling structure and heat-transfer conditions. For hot surface centricity, maximum surface temperature promotions are 30℃ and 15℃ with thickness increments of copper plates of 5 mm and nickel layers of 1 mm, respectively. The surface temperature without nickel layers is depressed by 10℃ when the depth increment of water slots is 2 mm and that with nickel layers adjacent to and away from mold outlet is depressed by 7℃ and 5℃, respectively. The specific trend of temperature distribution of transverse sections of copper plates is nearly free of cooling structure, but temperature is changed and its law is similar to the corresponding surface temperature.展开更多
The Ar-N2 gas tungsten arc(GTA) welding of 10 mm copper thick plates without preheating was investigated.The microstructure of weld metal and joints was observed and mechanical performance of weld metal was tested by ...The Ar-N2 gas tungsten arc(GTA) welding of 10 mm copper thick plates without preheating was investigated.The microstructure of weld metal and joints was observed and mechanical performance of weld metal was tested by using Cu-Ti welding metal with different Ti content.The Ar-N2 GTA weld of copper thick plates can eliminate the nitrogen porosities in the weld metal by adding element Ti in filler metal,which is caused by N2 gas in shield gas.The elimination degree of nitrogen porosities,the distribution of CuTiN intermetallic compound(IMC) and the mechanical performance of joints are associated with the change of the Ti content in the welding materials.And when Ti content is about 5%,nitrogen porosities is eliminated completely and the CuTiN IMC distribute dispersedly,the tensile strength and impact ductility of the joint achieve the best result,which almost reaches the lever of the base metal.展开更多
As a metal,copper comes in third only to iron and aluminum in terms of importance in national economy and as a non-ferrous metal,it ranks second in terms of consumption.The copper industry is a pillar of the non-ferro...As a metal,copper comes in third only to iron and aluminum in terms of importance in national economy and as a non-ferrous metal,it ranks second in terms of consumption.The copper industry is a pillar of the non-ferrous metal industry in China.In 2016,the copper industry’s assets accounted for23%of the national non-ferrous industry’s total,and its income accounted for 35%.China also holds展开更多
In China,the upstream industries of copper processing are copper ore dressing and copper smelting industries.But China’s copper industry has seen unbalanced development between the three steps:copper ore dressing,cop...In China,the upstream industries of copper processing are copper ore dressing and copper smelting industries.But China’s copper industry has seen unbalanced development between the three steps:copper ore dressing,copper smelting and processing.The industrialpattern where processing capacity is greater than smelting capacity,and smelting capacity展开更多
Micro prism film used in LCD industry can be manufactured by roll to roll method with copper-plated roll mold. As copper-plated roll mold is getting larger, pitch error is getting severer. The pitch error drops the qu...Micro prism film used in LCD industry can be manufactured by roll to roll method with copper-plated roll mold. As copper-plated roll mold is getting larger, pitch error is getting severer. The pitch error drops the quality of micro prism film. The main cause of the pitch error was investigated during machining large roll mold whose machined length was 1 200 mm. The temperature of machining system was elevated during machining roll mold, and this elevation induced thermal expansion of the system. The temperature variation around the roll mold also made thermal expansion of the roll mold. The amount of thermal expansion had strong relationship to the amount of pitch error. Therefore, the roll mold was machined after warming-up of machining system and precise temperature controller around copper-plated roll mold was installed, which minimized the temperature variation. Finally, precise micro prism patterns without pitch error were machined on the large roll mold.展开更多
[目的]在高度取向碳纳米管(SA-CNTs)薄膜表面均匀地镀上一层铜可以提高其电磁屏蔽性能,为其在柔性电路板、高速微处理器、雷达反射装置、移动通信设备等方面的应用奠定基础。[方法]首先对SA-CNTs薄膜表面进行碱性除油,然后采用多巴胺预...[目的]在高度取向碳纳米管(SA-CNTs)薄膜表面均匀地镀上一层铜可以提高其电磁屏蔽性能,为其在柔性电路板、高速微处理器、雷达反射装置、移动通信设备等方面的应用奠定基础。[方法]首先对SA-CNTs薄膜表面进行碱性除油,然后采用多巴胺预活化,在SA-CNTs薄膜上形成一层聚多巴胺层,为后续AgNO3活化提供更多的活化基点,并且由于聚多巴胺的还原性,AgNO3能够在SA-CNTs薄膜上直接形成纳米银微粒,有助于化学镀铜时快速起镀,最终在SA-CNTs薄膜表面获得均匀、致密的金属铜层。采用扫描电子显微镜(SEM)、能谱仪(EDS)和接触角测量仪研究了多巴胺预活化对化学镀铜的影响。通过正交试验优化了化学镀铜工艺,分析了较优工艺条件下所得Cu镀覆SA-CNTs薄膜的表面形貌、相结构和电磁屏蔽性能。[结果]经多巴胺预活化的SA-CNTs薄膜表面可有效快速地进行化学镀铜反应,施镀过程中镀液性能稳定,所得Cu镀层结合力良好,在4~18 GHz频段的平均电磁屏蔽效能达到103.07 d B。[结论]多巴胺预活化有利于促进SA-CNTs薄膜表面化学镀铜,提高薄膜的电磁屏蔽性能,值得在柔性电路板制作方面推广应用。展开更多
基金Project(51004031) supported by the National Natural Science Foundation of ChinaProject(50925415) supported by the National Outstanding Young Scientist Foundation of China+1 种基金Project(20100042120012) supported by the Special Research Fund for Doctoral Programs of Ministry of Education of ChinaProject(N090402022) supported by the Fundamental Research Funds for the Central Universities of China
文摘A three-dimensional finite-element model of slab continuous casting mold was conducted to clarify the effect of cooling structure on thermal behavior of copper plates. The results show that temperature distribution of hot surface is mainly governed by cooling structure and heat-transfer conditions. For hot surface centricity, maximum surface temperature promotions are 30℃ and 15℃ with thickness increments of copper plates of 5 mm and nickel layers of 1 mm, respectively. The surface temperature without nickel layers is depressed by 10℃ when the depth increment of water slots is 2 mm and that with nickel layers adjacent to and away from mold outlet is depressed by 7℃ and 5℃, respectively. The specific trend of temperature distribution of transverse sections of copper plates is nearly free of cooling structure, but temperature is changed and its law is similar to the corresponding surface temperature.
基金Funded by Program of Excellent Team in Harbin Institute of Technology
文摘The Ar-N2 gas tungsten arc(GTA) welding of 10 mm copper thick plates without preheating was investigated.The microstructure of weld metal and joints was observed and mechanical performance of weld metal was tested by using Cu-Ti welding metal with different Ti content.The Ar-N2 GTA weld of copper thick plates can eliminate the nitrogen porosities in the weld metal by adding element Ti in filler metal,which is caused by N2 gas in shield gas.The elimination degree of nitrogen porosities,the distribution of CuTiN intermetallic compound(IMC) and the mechanical performance of joints are associated with the change of the Ti content in the welding materials.And when Ti content is about 5%,nitrogen porosities is eliminated completely and the CuTiN IMC distribute dispersedly,the tensile strength and impact ductility of the joint achieve the best result,which almost reaches the lever of the base metal.
文摘As a metal,copper comes in third only to iron and aluminum in terms of importance in national economy and as a non-ferrous metal,it ranks second in terms of consumption.The copper industry is a pillar of the non-ferrous metal industry in China.In 2016,the copper industry’s assets accounted for23%of the national non-ferrous industry’s total,and its income accounted for 35%.China also holds
文摘In China,the upstream industries of copper processing are copper ore dressing and copper smelting industries.But China’s copper industry has seen unbalanced development between the three steps:copper ore dressing,copper smelting and processing.The industrialpattern where processing capacity is greater than smelting capacity,and smelting capacity
基金Project (2010-0008-277) supported by NCRC (National Core Research Center) Program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology, Korea
文摘Micro prism film used in LCD industry can be manufactured by roll to roll method with copper-plated roll mold. As copper-plated roll mold is getting larger, pitch error is getting severer. The pitch error drops the quality of micro prism film. The main cause of the pitch error was investigated during machining large roll mold whose machined length was 1 200 mm. The temperature of machining system was elevated during machining roll mold, and this elevation induced thermal expansion of the system. The temperature variation around the roll mold also made thermal expansion of the roll mold. The amount of thermal expansion had strong relationship to the amount of pitch error. Therefore, the roll mold was machined after warming-up of machining system and precise temperature controller around copper-plated roll mold was installed, which minimized the temperature variation. Finally, precise micro prism patterns without pitch error were machined on the large roll mold.
文摘[目的]在高度取向碳纳米管(SA-CNTs)薄膜表面均匀地镀上一层铜可以提高其电磁屏蔽性能,为其在柔性电路板、高速微处理器、雷达反射装置、移动通信设备等方面的应用奠定基础。[方法]首先对SA-CNTs薄膜表面进行碱性除油,然后采用多巴胺预活化,在SA-CNTs薄膜上形成一层聚多巴胺层,为后续AgNO3活化提供更多的活化基点,并且由于聚多巴胺的还原性,AgNO3能够在SA-CNTs薄膜上直接形成纳米银微粒,有助于化学镀铜时快速起镀,最终在SA-CNTs薄膜表面获得均匀、致密的金属铜层。采用扫描电子显微镜(SEM)、能谱仪(EDS)和接触角测量仪研究了多巴胺预活化对化学镀铜的影响。通过正交试验优化了化学镀铜工艺,分析了较优工艺条件下所得Cu镀覆SA-CNTs薄膜的表面形貌、相结构和电磁屏蔽性能。[结果]经多巴胺预活化的SA-CNTs薄膜表面可有效快速地进行化学镀铜反应,施镀过程中镀液性能稳定,所得Cu镀层结合力良好,在4~18 GHz频段的平均电磁屏蔽效能达到103.07 d B。[结论]多巴胺预活化有利于促进SA-CNTs薄膜表面化学镀铜,提高薄膜的电磁屏蔽性能,值得在柔性电路板制作方面推广应用。
