制备参数对反向凝固黄铜包覆纯铜绞线复合材料表面质量和界面结合状态的影响

Influences of preparing parameters on surface quality and interface bonding state of brass cladding copper stranded wire by inversion solidification

采用金属包覆材料反向凝固成形工艺制备外径为8.5 mm、芯材为d 2.12 mm×7 mm绞线的黄铜包覆纯铜绞线复合材料,研究制备参数对黄铜包覆纯铜绞线复合材料的表面质量、包覆层金属填充状态和界面结合状态的影响。结果表明:较高的复合腔黄铜熔体温度和较低的牵引速度,有利于防止复合材料表面缺陷的产生,改善表面质量;而较低的复合腔黄铜熔体温度和较高的牵引速度,有利于降低复合界面铜、锌原子的扩散和界面反应速率,有效减小铜绞线表面熔蚀程度。在复合腔中黄铜熔体与绞线的接触长度3mm、复合腔黄铜熔体温度1000~1020℃、牵引速度60~90 mm/min、结晶器冷却水流量400 L/h的条件下,制备具有良好表面质量和冶金结合界面的黄铜包覆纯铜绞线复合材料,黄铜包覆层的填充率达98%以上,抗拉强度为250~278 MPa,断后伸长率为39.1%~43.1%,电导率为53.1%~57.3%IACS。

A new inversion solidification technology for producing metal cladding material was used to produce brass cladding copper stranded wire with an outer diameter of 8.5 mm and a core material of d 2.12 mm×7 mm copper stranded wire. The influences of preparing parameters on the surface quality, filling state and interface bonding state of the brass cladding copper stranded wire were studied. The results show that the surface defects of the brass cladding copper stranded wire are eliminated and the surface quality is improved by enhancing the brass melt temperature in the composite cavity or decreasing the casting speed. On the other hand, decreasing the brass melt temperature or increasing the casting speed can reduce both the diffusions of copper atom and zinc atom as well as the interfacial reaction rate, which can suppress surface erosion of the copper stranded wire effectively. With the contact height of 3 mm between the brass melt and the core material, the brass melt temperature of 1000 ℃, the casting speed of 60-90 mm/min and the cooling water flow of 400 L/h, the produced brass cladding copper stranded wire has high surface quality, good metallurgical bonding interface, cladding layer filling rate of more than 98%,tensile strength of 250-278 MPa, elongation to failure of 39.1%-43.1% and electrical conductivity of 53.1%-57.3% IACS.