The effects of heat treatment on the microstructure and mechanical properties of ZA27 alloy were studied by X-ray diffraction(XRD),scanning electron microscopy(SEM) and mechanical characterization.The results indi...The effects of heat treatment on the microstructure and mechanical properties of ZA27 alloy were studied by X-ray diffraction(XRD),scanning electron microscopy(SEM) and mechanical characterization.The results indicated that the as-cast microstructure of the alloy was mainly composed of α,decomposed β,η and ε phases.After solid solution treatment at 365 ℃ for 1 h,α and η phases dissolved,and the microstructure of specimen was mainly composed of the supersaturated β phases.The phase decomposition of supersaturated ZA27 alloy is a two-stage phase transformation:the decomposition of the supersaturated β phase at the early stage of aging,and with the increase of aging time,ε phase decomposition through a four-phase transformation:α+ε→T '+ η.A good combination of high tensile elongation and reasonable strength can be achieved by suitable heat treatments.展开更多
基金Project(Z2011-01-002) supported by the Nonferrous Metals Science Foundation of Hunan Nonferrous Metals Holding Group Co.Ltd.- Central South University,China
文摘The effects of heat treatment on the microstructure and mechanical properties of ZA27 alloy were studied by X-ray diffraction(XRD),scanning electron microscopy(SEM) and mechanical characterization.The results indicated that the as-cast microstructure of the alloy was mainly composed of α,decomposed β,η and ε phases.After solid solution treatment at 365 ℃ for 1 h,α and η phases dissolved,and the microstructure of specimen was mainly composed of the supersaturated β phases.The phase decomposition of supersaturated ZA27 alloy is a two-stage phase transformation:the decomposition of the supersaturated β phase at the early stage of aging,and with the increase of aging time,ε phase decomposition through a four-phase transformation:α+ε→T '+ η.A good combination of high tensile elongation and reasonable strength can be achieved by suitable heat treatments.