Secondary Aging Effects in Copper - Chromium Alloy

Abstract

Copper Chromium alloys are been widely used in electrical contacts and electrical resistance electrodes for their durability during the welding process. In the welding process, the Cu-Cr alloy exposed high currents and high stamping pressure, the Cu-Cr alloys preferred in spot welding because of high electrical conductivity and high strength. In this study, it is aimed to increase mechanical strength more to restrain the plastic deformation of Cu-Cr alloys during welding. At least 1 % Cr containing spot welding tips of Cu-Cr alloys were treated for aging and secondary aging conditions. Secondary aging heat treatment processes are applied mostly to Aluminum alloys. In this study, the Cu-Cr alloy samples were aged at 650 oC for 4 hours. Secondary aging treatment was done at 400 oC for 2,4, and 6 hours. The maximum hardness value of Cu-Cr alloys was secondarily aged at 400 oC for 6 hours which was 10 % higher than the sample aged at 650 oC for 4 hours

Keywords

• Copper-Chromium Alloys
• Aging
• Microhardness
• Optical Microscopy

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