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 ram, 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
Multi-pass friction stir processing(M-FSP)was performed to repair the interface defects of AA5083/T2 copper explosive composite plates.The interface morphology and its bonding mechanism were explored.The results show ...Multi-pass friction stir processing(M-FSP)was performed to repair the interface defects of AA5083/T2 copper explosive composite plates.The interface morphology and its bonding mechanism were explored.The results show that higher rotation speed and lower transverse speed produce more heat generated during FSP.The defect-free and good mechanical properties of the AA5083/T2 copper composite plate can be obtained under the condition of the rotation speed of 1200 r/min,the transverse speed of 30 mm/min and the overlap of 2/24.Moreover,M-FSP changes the interface bonding mechanism from metallurgical bonding to vortex connection,improving the bonding strength of composite plate,which can guarantee the repairing quality of composite plates.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 ram, 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The authors are grateful for the financial supports from the National Natural Science Foundation of China(No.51505293)the Natural Science Foundation of Jiangsu Province,China(No.BK20190684)+1 种基金the Natural Science Research of the Jiangsu Higher Education Institutions of China(No.18KJB460016)the Key Laboratory of Lightweight Materials,Nanjing Tech University,as well as by a fellowship from the International Postdoctoral Exchange Followship Program(2020096 to Jian WANG).
文摘Multi-pass friction stir processing(M-FSP)was performed to repair the interface defects of AA5083/T2 copper explosive composite plates.The interface morphology and its bonding mechanism were explored.The results show that higher rotation speed and lower transverse speed produce more heat generated during FSP.The defect-free and good mechanical properties of the AA5083/T2 copper composite plate can be obtained under the condition of the rotation speed of 1200 r/min,the transverse speed of 30 mm/min and the overlap of 2/24.Moreover,M-FSP changes the interface bonding mechanism from metallurgical bonding to vortex connection,improving the bonding strength of composite plate,which can guarantee the repairing quality of composite plates.
