Rolling And Heat Treatment On The Microstructure And Properties Of Cu Alloy

This paper combines the lateral research project of “Research of Cu-Snconductor material smelting and rolling process”, and using the technology ofmold rapid cooling to prepare Cu-Sn, Cu-Fe, Cu-Sn-Fe alloy.And then treat thealloy with cold rolling and heat treatment to study microstructurevariation,mechanical properties and electrical conductivity of alloy, the mainresults are as follows:一、 From the study of Cu-Sn alloys we know that:Rapid solidificationtechnology can refine organization, expand the limit of solute Atomic insubstrate in the of solid dissolved degrees, make segregation weak, and hassmall effect on resistance. Grain are refined and drawn after rolling a, castingdefects (shrink pine, and shrinkage, and stomatal) is eliminated, strength is up to400Mpa, resistance was risen in a small degree. The annealed alloys has auniformed microstructure, clear interface, lower stress, good plasticity, goodtoughness, lower resistance, which can meet the need of contact wire, and havean excellent properties.二、 From the study of Cu-Fe alloys we know that:At sufficiently higherundercooling, the liquid separation will occur in the Cu-Fe alloys during itssolidification process, with a spherical particle formed on the Cu-rich matrix.Supersaturated atoms have precipitated after heat treatment, improving theelectrical conductivity of the alloy.After cold rolling, the electrical conductivitydegrades with the casting defect decreasing, while the mechanical propertiesinprove. So we can obtain copper alloys with good performance by choosingreasonable processing technology.Results showed that the tensile strength and the resistivity of the Cu-xSn-yFealloys (x、y represented wt.%, similarly hereinafter) increased with increasing thecontent of Sn and Fe. The resistivity of the Cu-xSn-yFe alloys increased afternormalizing treatment. Compared with the resistivity of the normalized alloys, itwas low after rolling. The resistivity of the alloys was influenced strongly by the variation of Sn content, and the conductivity of Cu-xSn-yFe alloys could beimproved by reducing the content of Sn. After annealing, Cu-xSn-yFe alloyresistivity significantly reduced and the tensile strength will be slightly reducedtoo. After cold rolling, the tensile strength of the Cu-3Sn-10Fe alloy reached775MPa, but its resistivity was only28.2IACS%. When the Fe content is5wt.%,Sn content to2wt.%, the alloy after annealing treatment between the tensilestrength of450~450Mpa, and electrical conductivity between50-65IACS%.