Development of Complex Methods, Combining Thermal Treatment with Severe Plastic Deformation, for Processing of High-Strength Nanostructured Cu-1Cr-0.7Al Alloy

摘要

The current work presents new results of investigation of properties and structure of nanocrystalline and submicrocrystalline Cu-l%Cr-0.7%Al alloy. Two severe plastic deformation (SPD) techniques were applied to refine the structure: high pressure torsion and equal-channel angular pressing (ECAP). The first technique was applied to conduct preliminary studies of the alloy different thermal treatments as before SPD as well as after it. A new technological thermo-mechanical technique for processing of bulk billets of Cu-1%Cr-0.7%Al alloy possessing an ultra-fine grained structure was developed on the basis of the obtained results. This technique comprises a combination of ECAP and other deformational processes with the thermal treatment. High values of the tensile strength and yield stress - 700 MPa and 16% accordingly - have been obtained as a result of such treatment, whereas these values after conventional treatment consisted 450 MPa and 20% respectively.