高强度低密度大模量菲晶态Ai—Li合金

利用单辊快速凝固装置制备出高强度、低密度、大楼量的非晶态Ａｌ６１Ｌｉ２．５Ｙ２５Ｎｉ１１．５（ｗｔ－％）合金，其最大拉伸断裂强度、显微硬度和弹性模量分别为１０３９ＭＰａ、４８８ＤＰＮ和９８．７ＧＰａ．与同成分的晶态合金相比，具有较高的电极电位、较宽的电压钝化区，其腐蚀抗力为晶态合金的７倍．在恒加热速率的晶化过程中出现４个晶化峰，晶化激活能的计算表明，Ａｌ６１Ｌｉ２．５Ｙ２５Ｎｉ１１．５非晶合金的晶化过程为一级反应．

ALUMINUM-LITHIUM AMORPHOUS ALLOYS WITH HIGH STRENGTH, LOW DENSITY AND LARGE YONG'S MODULUS

Al61Li2.5Y25Ni11.5(wt-%) amorphous alloys with high strength, low density and large Young's modulus were prepared by liquid quenching on a single roller melt-spinning apparatus. The highest tensile fractrue strength, Vickers hardness and Young's modulus of Al61Li2.5Y25Ni11.5 amorphous alloys reach 1039MPa, 488DPN and 98.7GPa respectively. Furthermore, the amorphous alloys were found to possess high electrode electric potential and wide voltage inaction range in comparison with the crystal alloys of same composition. The corrosion resistance of the amorphous alloy is about 7 times as high as that of the crystal alloys. Four exothermic peaks appear on DSC curves in the constant heating rate crystallization of the amorphous alloys. The activation energies of the crystallization phases, calculated by various methods,indicate that the crystallization process of Al61Li2.5Y25Ni11.5 amorphous alloys is first order reaction.