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The effects of heat treatment on the Cu-Zn-Al shape memory alloys with mixed RE were researched with the help of X-ray diffraction and transmission electron microscope (TEM). The results show that the shape memory alloys with martensite can be produced by adding mixed RE and heat treatment processes holding at 820℃-880℃ for 15mm, quenching into oil, aging at 150℃ for 15min, and then holding in water at 50℃ for 10min. The alloys have the lowest transformation thermal hysteresis. Among the four experimental heat treatment processes the gradationally quenching makes the alloy have the highest transformation temperature and quenching into oil or water at room temperature makes the alloy have the largest thermal hysteresis. Mi- crostructure examination shows that aging at 200℃ could destroy the substructures in lathy martensites in the alloy and form a lot of dislocations, and aging at 250℃ could cause the bainite transformation in the alloy.
The effects of heat treatment on the Cu-Zn-Al shape memory alloys with mixed RE were researched with the help of X-ray diffraction and transmission electron microscope (TEM). The results show that the shape memory alloys with martensite can be produced by Adding mixed RE and heat treatment processes holding at 820-880 ° C for 15mm, quenching into oil, aging at 150 ° C for 15min, and then holding in water at 50 ° C for 10min. The alloys have the lowest transformation thermal hysteresis. Among the four experimental heat treatment processes the gradationally quenching makes the alloy have the highest transformation temperature and quenching into oil or water at room temperature makes the alloy have the largest thermal hysteresis. Mi- crostructure examination shows that aging at 200 ° C could destroy the substructures in lathy martensites in the alloy and form a lot of dislocations, and aging at 250 ° C could cause the bai nite transformation in the alloy.