| Summary: | 碩士 === 國立東華大學 === 材料科學與工程學系 === 105 === In order to extend the application of magnesium alloys in the automotive field, the strengths of rare-earth element added magnesium alloys at ambient and elevated temperature were investigated. In this research, the Mg97Zn1(MM-La)2 and Mg97Zn1(MM-Ce)2 alloy billets were extruded into planes. According to the tensile test results, both as-extruded alloys possess high tensile yield strength over 250 MPa. Besides, it was observed in the high temperature tensile test at 473 K that both alloys still keep high yield strength of 200 MPa. According to the nano-indentation test result, the second phase has much higher hardness than the matrix and thus, the strengthening mechanisms were composite strengthening. In XRD results, both alloys comprise two phases of h.c.p.-Mg and REMg12
|
|---|
