Study on Properties and Mechanism of Si-Reinforced Zn-Al Alloys
Wear resistance of Zn-Al alloys declines sharply at high-speed overload, or poor lubrication, friction interface adhering. It is necessary to further improve the properties of Zn-Al alloys. Silicon were added into Zn-Al alloys as reinforcement (Si from 3%, 5% to 7%) and modified with mixed salt (sodiums, CaF2 and KCl ) and mixed rare earth(La and Ce oxides).Research determined the hardness, tensile toughness, wear quantities (at room and high temperature), observed the microstructure of alloys, analyzed the modification mechanism of modifier on silicon ,and selected a better sample for testing of high temperature wear resistance and high speed friction- rotating. The results show that silicon phases are significantly modified from sheet to spheroid, the properties are further improved because of silicon as hard phase in alloys, especially, the high temperature properties increases greatly, adhering temperature increases from below 170°C to above 250°C.