Effect of rare earth additions on microstructure and
mechanical properties of AZ91 magnesium alloys
mechanical properties of AZ91 magnesium alloys
(1. Key Laboratory of Automobile Material, Ministry of Education,
Department of Materials Science and Engineering, Jilin University, Changchun 130025, China;
2. Research & Development Center, First Automobile Work (FAW) Foundry Co. Ltd., Changchun 130062, China)
Department of Materials Science and Engineering, Jilin University, Changchun 130025, China;
2. Research & Development Center, First Automobile Work (FAW) Foundry Co. Ltd., Changchun 130062, China)
Abstract: In order to meet the demands of high temperature components in automobile, the microstructure and mechanical properties of several new die-casting AZ91-rare earth (RE) magnesium alloys were studied. The alloys were characterized by optical microscopy (OM), scan electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), tensile and creep tests. The results show that Ce addition has little effect on the mechanical properties of AZ91 alloy at high temperature, while Y and Nd addition play important role in the improvement of creep resistance. New alloys containing Y or Nd with excellent high temperature performance are selected to produce cylinder head cover of high power diesel engine of Red Flag car and oil pan of Besturn car. The new magnesium alloys with RE addition for die-casting have potential to produce power-train parts, and can greatly decrease weight.
Key words: magnesium alloy; rare earth; die-casting; high temperature; creep; microstructure