| In this thesis, the phase diagram of Zn-Al binary system on 10~69.5 w(Zn)% was reinvestigated by using differential scanning calorimeter (DSC), X-ray diffraction (XRD) and pushrod dilatometer (PRD). The process of isothermal transformation during the aging of high-Aluminum-Zinc-based alloy was studied by using differential scanning calorimetry (DSC), and the aging behavior of the alloy was analyzed at the aspect of thermal analysis kinetics. The change of microstructure which the alloy was being heated was observed on high-temperature metallurgical microscope. The microstructure and wear-friction properties were compared among the alloys treated with several different heat treatment processes, and a model for heat treatment processes was proposed based on artificial neural network,so as to predict the relationship between friction coefficient and parameters of aging treatment such as aging temperature and time. The results showed that:(1) The Zn-Al binary phase diagram of 10~69.5 w(Zn)% built by experiment was similar to fig.1-1(b). There exist the β(ZnAl) solid solution single phase zone, butnon-transformation was discovered at 340℃.(2) The activation energy of aging reaction for ZA27 alloy was low, and the aging process was fast. Remarkable exothermic phenomenon was observed during the aging process. Less the transformation enthalpy, shorter the incubation time, and easier the transformation proceeding.(3) When ZA27 alloy was aged at 100℃, which was quenched into ice water after solution treatment, the precipitation of η phase and a phase occurred quicklyin the β phase base as a discontinuous way. Then celluar decomposition of β phase...
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