Naslov
Influence of Ausforming Treatment on Super Elasticity of Cu-Zn-Al Shape Memory Alloy for Seismic Energy Dissipaters

Autori
Ćorić, Danko ; Žmak, Irena

Izvornik
Buildings (2075-5309) 11 (2021), 1, 22; 1-15

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Cu-Zn-Al ; shape memory ; SMA ; seismic ; ausforming ; transformation temperatures ; super elasticity ; microstructure

Sažetak
In order to develop the application of the more cost-effective copper-based shape memory alloys (SMAs), rather than nickel-titanium as earthquake energy dissipaters, the influence of ausforming induced plastic deformation on phase transformations, microstructure, super-elasticity and mechanical properties of the shape memory alloy Cu-26Zn-4Al was examined. These specific SMA properties were targeted by applying appropriate parameters of the thermo-mechanical (the so-called ausforming) process: beta-phase homogenization at 800 °C for 20 minutes, one-step hot-rolling at 800 °C and water quenching. The results showed significant microstructural changes, increased mechanical resistance and change in the phase transformation behavior. The SMA treated by ausforming retained the reversible austenitic-martensitic transformation ability, with the appearance of the super-elastic effect up to 6 % of strain recovery. Although some strengthening occurred after hot-rolling (an increase in true yield strength of 125 MPa was detected), all phase transformation temperatures were decreased. The smallest decrease was detected for the austenite finish temperature (32.8 °C) and the largest for the martensite finish temperature (42.0 °C), allowing both the expansion and the lowering of the temperature range of super-elasticity, which is favorable for constructional applications. It is concluded that it is possible to achieve an optimal combination of adequate strength and improved transformation behavior of Cu-Zn-Al alloy by applying the ausforming treatment.

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo, Temeljne tehničke znanosti

POVEZANOST RADA