Crystallization behavior and consolidation of gas-atomized Al84Gd6Ni7Co3 glassy powder
Crystallization behavior and consolidation of gas-atomized Al84Gd6Ni7Co3 glassy powder
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DOI：
10.1016/j.jallcom.2009.10.178
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发表时间：
2010-02
影响因子：
6.2
通讯作者：
K. Surreddi;S. Scudino;M. Sakaliyska;K. Prashanth;D. Sordelet;J. Eckert
中科院分区：
文献类型：
--
作者：
K. Surreddi;S. Scudino;M. Sakaliyska;K. Prashanth;D. Sordelet;J. Eckert
气雾化 Al84Gd6Ni7Co3 玻璃粉末表现出双步失透行为，其特征是在结晶过程的第一阶段析出面心立方 Al，然后在随后的结晶过程中形成金属间相。结晶动力学的研究表明，玻璃到面心立方铝转变的初始部分是通过扩散控制生长进行的，成核率不断增加，而转变的后期阶段主要是形成的核的生长，而不是新核的生成。高密度块状样品是通过玻璃前体的失透和固结相结合的热挤压来生产的。固结样品表现出约 1130MPa 的显着高强度和 3% 的断裂应变。
Gas-atomized Al84Gd6Ni7Co3glassy powder displays a double-step devitrification behavior characterized by the precipitation of fcc Al in the first stage of the crystallization process, followed by the formation of intermetallic phases in the following crystallization event. Investigation of the crystallization kinetics reveal that the initial part of the glass-to-fcc Al transformation occurs by diffusion controlled growth with an increasing nucleation rate whereas the later stage of the transformation is dominated by the growth of the formed nuclei rather than by the generation of new nuclei. Highly dense bulk samples were produced by hot extrusion through the combined devitrification and consolidation of the glassy precursor. The consolidated samples exhibit remarkable high strength of about 1130MPa combined with 3% fracture strain.