Evolution of the microstructure and mechanical properties of the Cu-47Pd (at %) alloy during atomic ordering after severe plastic deformation

Abstract

The possibility of severe plastic deformation of the Cu-47Pd (at %) alloy by room temperature rolling to high degrees without intermediate anneals has been shown. The microstructure and physicome chanical properties of ribbons 100 and 4.5 μm thick in the initial strongly deformed state (the true degree of deformation ε ≈ 4.4 and ε ≈ 7.5, respectively), as well as after thermal treatments of various durations have been studied. High alloy plasticity during rolling is explained by recovery processes, which occur in the mate rial during SPD. The formation of single phase B2 type ordered state, which diverges with the phase dia gram, is found. , wt % Temperature, °С Temperature, К В2(bcc) High hydrogen permeability А1(fcc) Low hydrogen permeability А1 + В2 Cu-47 at % Pd (60 wt %) Fig. 1. Portion of the phase diagram of Cu-Pd alloys with B2 type ordering [1].

Microstructure of an equiatomic CuPd alloy after severe plastic deformation and subsequent ordering

“…Ранее нами было установлено, что такая высокая пластичность сплавов Cu-(47-55) ат. % Pd объясняется процессами динамического возврата [6].…”