Quenching and ageing behaviour of quaternary Cu-Zn-Al-Ni single crystals

E. Zelaya, J. L. Pelegrina, M. Ahlers
2001 Journal de Physique IV : Proceedings  
The ageing behaviour of the martensite in single crystals made from the quaternary alloy (Cu -9.04 at%Zn -20.87 at%Al -3.07 at%Ni) was investigated, together with a characterization of the structure and the microstructure in the initial condition. The long range ordering temperatures were determined by electrical resistivity measurements. The stabilization of stress induced martensite was quantitatively studied as a function of time and temperature. After performing the same thermal treatment
more » ... thermal treatment as for the ageing experiments, slices for transmission electron microscopy were cut and the resulting structure and microstructure were analyzed. The high temperature (3 phase is long range ordered and the martensite has the 18R structure. No evidence for the appearance of y precipitates was found after a quench from 770 K. However, a large number of vacancy loops with straight borders lying in {1 0 0} planes were present, with the corresponding dislocations dissociated in partials. It was also found that the stabilization process takes place in the martensite, but with a slower kinetics than in Cu-Zn-Al.
doi:10.1051/jp4:2001826 fatcat:kvzy2fd3xzdirbr6g7cpbrbln4