The Effects of Compound Alloying Elements Cr, Sb and Ce on the Precipitation Process of Casting Mg-IOZn-2Al-ICu Alloy
The effects of compound added alloying elements including Sb, Ce and Cr on the precipitation process of casting Mg-10Zn-2Al-1Cu alloy were studied by field-emission transmission electron microscopy (JEOL - 2100F, 200kV) , Xray diffraction and other experimental means. The results showed that, during 360℃ x lOh solution treatment and 160 ℃ aging treatment, the early stage of aging structure of experimental alloy had significant features of GP zones ; in the peak aging, the evenly distributed precipitated phase was clavate, platelike or granular and some rod-like precipitates parallel with (0001) Mg, others intersecte with (0001) Mg ; after over-aging treatment, although the precipitates coarsening occurred which made them become banding or spherical, the coarsening rate decreased significantly. The precipitates may include 13Mg17Al12, (Mg32 (Al, Zn) 49) , AlMg4Zn11, CeCuAl, Al4Cu9, CrSb2, Mg2Zn3, etc. The hardening curve of experimental alloy showed the typical character of temperature and aging, and its hardening incubation period is short, the age-ardening rate is high and the rate of hardness decline after over-aging is relatively slow. Thus compound added alloying elements Cr, Sb and Ce could accelerate atom segregation and nucleation at the early stage of aging and increase the stability of the precipitates, inhibit the growth of precipitates during late aging.
alloying elements precipitate precipitation hardening stability coarsening rate
Lin Xiaoping Dong Yon Li Haipeng Qi Zhenhua Ye Jie
School of Materials Science and Engineering,Northeastern University at Qin huangdao,Qinhuangdao 066004,China
国际会议
69th World Foundry Congress(第69届世界铸造会议 WFC 2010)
杭州
英文
338-341
2010-10-16（万方平台首次上网日期，不代表论文的发表时间）