图书来源:二元合金相图及中间相晶体结构 二元合金相图及中间相晶体结构
作 者:唐仁政 田荣璋
出版时间:2009-05
定 价:320元
图书ISBN:978-7-81105-831-4
出版单位:中南大学出版社
Zhongwei CHEN , Cuiying MA and Jing ZHAO State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi an 710072, China
摘 要:The nucleation of eutectic crystals of hypoeutectic Al-7 wt pct Si-Mg casting alloys modified by Ce and Sr was studied by using differential scanning calorimeter (DSC) and scanning electron microscope (SEM). DSC results were applied to calculate the values of activity energy and nucleation work of eutectic nucleation for the alloys. These values were decreased and the eutectic nucleation frequency was increased with the addition of Ce and Sr to the alloys. Moreover, the morphology of eutectic silicon in the modified alloys was partially or fully modified as fine, fibrous or coral, and DSC plots show that the eutectic undercooling of Al-7 wt pct Si-Mg alloys were increased with additions of modified agents. The mechanism of eutectic modification is combined actions of the accelerated nucleation and the restricted growth.
关键词: