Microstructure, mechanical properties and creep resistance of Mg-(8%-12%)Zn-(2%-6%)Al alloys
(1. School of Mechanical Engineering, Nantong University, Nantong 226019, China;
2. Department of Mechanical Engineering, Zilang College, Nantong 226019, China)
2. Department of Mechanical Engineering, Zilang College, Nantong 226019, China)
Abstract: The microstructural characteristics, mechanical properties and creep resistance of Mg-(8%-12%)Zn-(2%-6%)Al alloys were investigated to get a better overall understanding of these series alloys. The results indicate that the microstructure of the alloys ZA82, ZA102 and ZA122 with the mass ratio of Zn to Al of 4-6 is mainly composed of α-Mg matrix and two different morphologies of precipitates (block τ-Mg32(Al, Zn)49 and dense lamellar e-Mg51Zn20), the alloys ZA84, ZA104 and ZA124 with the mass ratio of 2-3 contain α-Mg matrix and only block τ phases, and the alloys ZA86, ZA106 and ZA126 with the mass ratio of 1-2 consist of α-Mg matrix, block τ precipitates, lamellar f-Al2Mg5Zn2 eutectics and flocculent β-Mg17Al12 compounds. The alloys studied with the mass ratio of Zn to Al of 2-3 exhibit high creep resistance, and the alloy ZA124 with the continuous network of τ precipitating along grain boundaries shows the highest creep resistance.
Key words: Mg-Zn-Al alloys; microstructure; mechanical property; creep resistance