摘要
用X射线衍射(XRD)分析方法,探讨了AB_5型稀土贮氢合金在不同冷却速度下织构的生长特性及其对电极性能的影响。在普通快冷条件下,具有不同成分的贮氢合金锭呈不同的织构生长特性,一般具有(101)+(002)晶面择优取向,平行于冷却面,并可获得较高的放电容量;在快速凝固条件下制得的贮氢合金,其表面呈强的(0002)基极织构也即c轴织构,与稀土贮氢合金M_mNi_(3.5)Co_(0.7)Al_(0.8)锭的柱状晶结构具有强的c轴织构取向以及定向凝固合金在不同冷却速率下的织构取向相一致。
By using X-ray diffraction technique and electrochemical measurement, the texture growth and its effects on the electrochemical properties have been explored under various cooling rates in rare-earth hydrogen storage alloys. The results showed that ;① the different texture growth characters were observed in hydrogen storage alloys with various compositions at a conventional faster cooling and a columnar structure was formed so that the c axis of the hexagonal structure was oriented parallelly to the cooling plane and attained a higher capacity; ② the alloy prepared froNo rapid solidification exhibits (0002) based pole texture in the surface of alloy plate i. e. c axis texture. Its crystal growth characters were consistent well with the alloy MmNi3. 5Co0. 7 A10.8 which had a columnar structure with a very high endurance and low lattice strain obtained under controlled conditions, including high cooling rate in the casting process for obtaining a columnar structure.
出处
《物理测试》
CAS
1999年第6期11-16,共6页
Physics Examination and Testing
基金
国家自然科学基金
关键词
稀土贮氢合金
织构
快速凝固
放电容量
循环寿命
rare earth hydrogen storage alloy, texture, rapid solidification, capactity, cycle life
