Effects of filter materials on microstructure and mechanical properties of AZ91  

作　　者：Wu Guohua Sun Ming Dai Jichun Ding Wenjiang 

机构地区：[1]National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, Shanghai 200240, China [2]State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China

出　　处：《China Foundry》2010年第4期400-407,共8页中国铸造（英文版）

基　　金：supported by Program of Shanghai Subject Chief Scientist (No.08XD14020);National Basic Research Program of China (No.2007CB613701);National High Technology R&D Program of China (No.2009AA033501);Aerospace Science and Technology Innovation Fund of China Aerospace Science and Technology Corporation (No.0502)

摘　　要：The present investigation studied the effects of different kinds of ceramic foam filters (CFF) incorporating gas bubbling on the microstructure and mechanical properties of virgin AZ91 alloys, and the reactions between filters and Mg melt during filtration. The results show that the purification process of CFF incorporating gas bubbling process can obviously improve the R m and A of AZ91 alloy, especially the A. Amongst the selected four kinds of CFF, the MgO filter is the most suitable for filtrating Mg melt, and the filtration effective sequence of four kinds of filtrating materials is as follows: MgO>Al2O3>ZrO2>SiC. With MgO filter incorporating gas bubbling treatment under Ar flow rate of 2 L/min and temperature of 730 °C, the ultimate tensile strength R m and elongation A can be improved greatly from 175.3 MPa and 2.74% to 195.4 MPa and 4.54%, respectively. No inclusions are found on the fracture surface of the sample filtrated by MgO ceramic foam filter, and the fracture mode is quasicleavage crack.The present investigation studied the effects of different kinds of ceramic foam filters （CFF） incorporating gas bubbling on the microstructure and mechanical properties of virgin AZ91 alloys, and the reactions between filters and Mg melt during filtration. The results show that the purification process of CFF incorporating gas bubbling process can obviously improve the R m and A of AZ91 alloy, especially the A. Amongst the selected four kinds of CFF, the MgO filter is the most suitable for filtrating Mg melt, and the filtration effective sequence of four kinds of filtrating materials is as follows： MgO〉Al2O3〉ZrO2〉SiC. With MgO filter incorporating gas bubbling treatment under Ar flow rate of 2 L/min and temperature of 730 °C, the ultimate tensile strength R m and elongation A can be improved greatly from 175.3 MPa and 2.74% to 195.4 MPa and 4.54%, respectively. No inclusions are found on the fracture surface of the sample filtrated by MgO ceramic foam filter, and the fracture mode is quasicleavage crack.

关 键 词：magnesium alloy ceramic foam filters （CFF） INCLUSION PURIFICATION 

分 类 号：TG146.22[一般工业技术—材料科学与工程]