摘要
The microstructure and hardness of rheo-forming AZ91-Y alloy before and after solution treatment(ST)have been investigated by means of optical microscope(OM),scanning electron microscope(SEM)equipped with energy dispersive spectroscopy(EDS),X-ray diffraction(XRD)and Vickers.The experimental results showed that theβ-Mg17Al12 phase of alloy was nearly dissolved after ST for 5 min.With the increasing of ST duration to 28 h,both the primary and secondarily solidifiedα-Mg grains faded away.At the same time,the alloy exhibited a much smoother surface due to the diffusion of solute atoms(Al).During ST,the thermal stable phase of Al2 Y produced by ultrasonic vibration retained its size and morphology.As the ST duration was increased,the alloy hardness decreased sharply at first,and then gradually reached a minimum level.The alloy's appropriate ST duration at 410°C was approximately 28 h.
基金
financially supported by the National Science Foundation of China(51165032)
Ministry of Education Special Research Fund of the Doctoral Program for Higher Education(20133601110001)
Innovative Group of Science and Technology of College of Jiangxi Province(00008713)
the Production,Teaching and Research Cooperation Plan of Nanchang Non-party Experts and Doctors(2012-CYH-DW-XCL-002)
