Wire And Cable With Al - Fe - Cu Alloy Microstructure And Properties Research

Aluminum alloys employed in wire and cable industry requires good conductivity,good heat resistance and corrosion resistance,as well as good mechanical properties. Al-Fe-Cu alloy is a new type of heat-resistant alloy. High temperature mechanical properties and tough was improved with the addition of small amount Fe element. In this paper, in order to study the influence of Fe/Cu ratio on the the microstructures and properties, Al-Fe-Cu aluminum alloys with different mass percentage of Fe and Cu element were designed.By means of Vickers hardness measurement,conductivity measurements,room temperature tensile test, optical microscopy(OM), scanning electron microscopy(SEM) and transmission electron microscopy (TEM) observations,the microstructure evolution and mechanical properties of Al-Fe-Cu alloy at different state was studied,so as to get the the best plan of alloy component. The effect of annealing on the evolution microstructure and mechanical properties of cold drawn Al-0.7Fe-0.2Cu alloy was fully researched,meanwhile,the evolution of recrystallization texture in Al-0.7Fe-0.2Cu aluminum alloy was observeed.The main conclusions are as following:(1) The second phase of Al-Fe-Cu alloy is Al(Fe,Cu), with the shape of elliptic-oblong, about0.5μm。Fe/Cu ratio can influence the chemical composition of second pahse,but the shape. Partial Cu element in primary phase Al(Fe,Cu) had dissolved in Al matrix after annealing at300℃/2h, and nearly all the Cu element dissolved in Al matrix when the alloy was treated at500℃for2h, about0.2μm, wich made the decrease of electrical conductivity owing to lattice distortion.(2) For the hot extrusion state of Al-Fe-Cu aluminum alloy, when the Cu conten is about0-0.2%, the electrical conductivity is about60%IACS,tensile strength is about110MPa,when the Cu conten is about0-0.4%, the electrical conductivity decreased55%IACS, tensile strength is about120MPa,wich made the decrease of electrical conductivity owing to lattice distortion, meanwhile it can strengthen the alloy efficiently. (3) The electrical conductivity of Al-Fe-Cu aluminum alloy are aboe61%IACS after annealing at300℃.The tensile strength of Al-0.7Fe-0.4Cu can attain114MPa after annealing at400℃. The best comprehensive properties alloy is Al-0.7Fe-0.2Cu, the electrical conductivity is about61.98%IACS,tensile strength is about108MPa and elongation is about30%after annealing at300℃for2h.(4) The recrystallization temperature of the cold drawn Al-0.7Fe-0.2Cu wire is in the range of300℃～350℃.The second phase can prevent the recrystallization grain from growing up. The recrystallization grain size is about20-25μm after annealing at450℃from4min to4h.There is abnormal grain growth after annealing at450℃for13h, with grain size about50μm.The mainly texture is Copper texture,and Goss texture is the mainly texture during recovery.