Influence of phosphorus additions on annealing behaviour of cold-worked copper

Abstract

Abstract High-purity copper and two alloys containing 0.16 and 0.76 wt-% phosphorus have been examined after 95% cold-rolling and subsequent annealing treatments. In the cold-rolled state the pure copper and the dilute alloy are similar in almost every respect but differ significantly from the more concentrated alloy in structure and texture. On annealing, the two alloys behave similarly showing a marked retardation in recovery and recrystallization when compared to the pure copper. The growth rate of recrystallized grains is more strongly inhibited by phosphorus than is their nucleation, and this leads to substantial modification in the as-recrystallized structures and textures. Evidence for segregation of phosphorus atoms to the dislocation substructure is found in the recovery kinetics, the release of stored energy at low temperatures, and in strain-ageing effects during mechanical testing. Modification of annealing behaviour in the alloys may be attributed to segregation of phosphorus atoms at lattice...