熔体旋淬合金Zr_(0.9)Ti_(0.1)(Ni,Co,Mn,V)_(2.1)的微结构与电化学性能

Microstructure and Electrochemical Properties of the Melt_Spinning Zr_(0.9)Ti_(0.1) (Ni,Co,Mn,V)_(2.1) Alloy

对比研究了熔体旋淬和常规熔铸合金Zr0 .9Ti0 .1(Ni,Co ,Mn ,V) 2 .1的微结构和电化学性能 .XRD分析表明 :熔体旋淬合金在退火前后的晶体结构和铸态合金一样 ,均为面心立方结构 ,由LaveC15相组成 ;并且随旋淬速度的增加 ,旋淬合金中的非晶成分越多 .电化学测试表明 :旋淬合金有较好的活化性能 ,但其最大放电容量较低 ,小于 2 80mAh/g ;而退火后的旋淬合金需经 30次循环才能完全活化 ,其最大放电容量皆为 34 0mAh/g左右 ,高于铸态合金和退火前的旋淬合金 ;在电流密度为 30 0mA/g下进行充放电循环 ,发现退火后的旋淬合金循环稳定性明显高于铸态合金电极 ,并且随旋淬速度的增加 ,循环稳定性越好 ,经过 80 0次循环后 ,退火后的 4 0m/s合金容量保持率高达 85 % ,容量衰减率只有 6.9%

The microstructure and electrochemical properties of Zr 0.9 Ti 0.1 (Ni,Co,Mn,V) 2.1 alloys prepared by both the melt_spinning method and the conventional induction melting were investigated. XRD studies show that Zr 0.9 Ti 0.1 (Ni,Co,Mn,V) 2.1 alloys at as_cast,melt_spinning and annealing are all face center cubic structure with C15 laves phase,the higher the melt_spinning rate,the more the amorphous content.The electrochemical measurements show that melt_spinning alloys have better active behavior,low discharge capacity(<280 mAh/g); but after annealed,the alloys are activated completely with 30 cycles, the capacities about 340 mAh/g are higher than those of as_cast and melt_spinning alloys;the annealec alloys have a better cycle stability than that of as_cast alloy, and the higher the melt_spinning rate is, the more stable the alloy becomes; at 300 mAh/g current density,the capacity of annealed 40 m/s alloy is up to 85% of the maximum capacity after 800 cycles, the capacity decay rate is about 6.9%.