Investigation of precipitation during recrystallisation in two phase Cu-Cr alloy

Abstract

Copper-Chromium Alloy is high strength and high conductivity material. The As-Cast microstructure will show dendrites with rich chromium precipitates in the interdendritic region. In the present work precipitation and recrystallization are studied simultaneously. Precipitation gives high strength to the alloy whereas recrystallization will tend to soften the material. Recrystallization is nucleation of strain free grains in the deformed matrix. Precipitation from the super saturated solid solution results in the formation of precipitates in the matrix of copper alloy. These precipitates are dislocation barriers during slip process and enhance the strength and hardness of the alloy. Precipitation occurs at heterogeneous nucleation sites like high angle grain boundaries, dislocations, and second phase particle interfaces etc. Recrystallization on the other hand is motion of high angle grain boundaries. Precipitation in copper-chromium alloy before recrystallization, during recrystallization and after recrystallization is studied by Microstructural analysis using Optical and Scanning electron microscope. The hardness of the alloy is also evaluated and the hardness of As-cast structure increased after cold rolling and decreased after annealing for a varying time periods.