PROCESS FOR PREPARING A CU-ZN-AL ALLOY AND A SHAPE MEMORY BLANK

摘要

The invention relates to a process for preparing a Cu-Zn-Al alloy of higher shape memory characteristics, made of composite depositions on a substrate of various shapes, using the powder metallurgy-specific double-jet pulverization method. According to the invention, the process for preparing an alloy comprising 70% Cu, 26% Zn and 4% Al in mass percentage, obtained from highly pure starting materials, of 99.5%, includes the preparation of a Cu-Al smelt and disintegration thereof as very fine drops, under the action of a strong 99.9%-pure argon jet, whereinto Zn as powder is simultaneously injected, cooling and solidification of the pre-alloyed powders, followed by admixing 3% zinc stearate and cold-pressing the mixture, at a pressure of 300 MPa, sintering of the compacted products in furnaces, under a protective argon atmosphere, at a temperature of 960°C, for 2 hours, with slow cooling inside the furnace, followed by 15...20 cycles of hot plastic deformation by rolling at 800°C, with water cooling, a secondary thermal treatment of recrystallization at 920°C, for 15 min, with water cooling, the alloy as laminas being finally subjected to training by undergoing 10 charging-discharging-heating-cooling cycles, depending on the type of strain it will be subjected to.