Effect of chemical composition and quenching media on recoverable strain in Cu–Zn–Al alloys

Influence of Heat Treatment on Microstructures and Shape Memory Effect of Cu-28Zn-2.5Al wt. % Produced by Gravity Casting

“…This indicates that the secondary phase is α [A1], which is then referred to as retained α[A1]. Meanwhile, the matrix is βˈ [M18R] with V shape morphology, similar to the βˈ phase as in Asanovic et al [21], [22]and Lohan et al [6]. The XRD test results are displayed in Figure 7 and Table 5.…”

“…Then, it can be concluded: that UQ treatment by using SD (saltwater + dry ice) is effective in increasing SME. In addition, Asanovic et al [22] also mentioned that using the UQ method improved the ability to remember the shape of the alloy (SME) by preventing the formation of stable martensite. However, in this work, the increase in SME is not significant due to the relatively high retained α phase (23.5 -30.5%).…”

“…The applied thermal energy during UQ helped the martensite to finish the ordering reaction, annihilate excess vacancy, as well as eliminate residual stresses due to quenching. Hence, the martensite stabilization is reduced, and the reverse phase transformation from martensite to austenite can be easily facilitated [13], [14], [22]. Other than quenching methods and quenching media in the development process of the shape memory alloy, it is necessary to look at the composition of the alloy and ratio of the phase contained in the alloy, as the initial characteristics of the material before treatment is defining the shape memory capability.…”