学术论文

      放电等离子烧结制备Mg2-xNdxNi(x=0~0.3)储氢合金

      Preparation of Mg2-xNdxNi(x=0~0.3) hydrogen storage alloys by spark plasma sintering

      摘要:
      采用放电等离子烧结(SPS)工艺制备了Mg2-xNdxNi(x=0,0.1,0.2,0.3)储氢合金.通过X射线衍射(XRD)和扫描电镜(SEM)研究了合金的相结构和表面形貌,利用等容压差法分析测试了合金的压力--组成--温度(PCT)曲线和吸放氢动力学性能,研究了烧结温度、稀土元素Nd对储氢合金微观组织结构和储氢性能的影响,比较了SPS技术与真空感应熔炼法制备的Mg基合金组织结构和储氢性能的异同.结果表明:SPS制备的Mg2-xNdxNi(x=0~0.3)系列储氢合金具有多相结构,储氢合金的吸放氢动力学性能良好;Nd元素有利于Mg合金化,不利于储氢量;烧结温度对储氢量、PCT曲线平台性能有明显影响;当Mg2-xNdxNi系合金中含有Mg和NdMg12相,PCT曲线出现双平台现象;与铸态合金相比,SPS制备的Mg1.7Nd0.3Ni储氢合金的吸放氢动力学性能较好,但储氢容量、放氢率和PCT曲线平台性能更差.
      Abstract:
      The effects of sintering temperature and rare element Nd on the phase structures,morphology,pressure-composition-temperature(PCT) curves and hydrogen absorption/desorption kinetics characteristics of Mg2-xNdxNi(x=0,0.1,0.2,0.3)alloys prepared by spark plasma sintering(SPS) were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM) and PCT experiments.The structures and hydrogen storage properties of the Mg-based alloys prepared by SPS and vacuum induction melting were compared.It is shown that Mg2-xNdxNi alloys prepared by SPS exhibit a multiphase structure,demonstrating better hydrogen absorption/desorption kinetics performances but deterioration in hydrogen storage capacity with increasing Nd content,and Mg alloying is prompted by Nd.Sintering temperature has an obviously effect on the hydrogen storage capacity and the plateau properties of PCT curves.When Mg2-xNdxN alloys contain Mg or NdMg12 phase,their PCT curves exhibit two platforms.Compared with the alloys prepared by casting,the Mg1.7Nd0.3Ni hydrogen storage alloy prepared by SPS has better absorption/desorption kinetics properties but awful hydrogen storage capacity,hydrogen desorption rate and platform properties of PCT curves.
      作者: 李平 [1] 万琦 [1] DIN Raft-ud [1] 谢东辉 [2] 曲选辉 [3]
      作者单位: 北京科技大学材料科学与工程学院,北京,100083 北京北冶功能材料有限公司,北京,100192 北京科技大学材料科学与工程学院,北京100083/北京市先进粉末冶金材料与技术重点实验室,北京100083
      刊 名: 北京科技大学学报 ISTICEIPKU
      年,卷(期): 2011, 33(8)
      分类号: TG139.7
      机标分类号: TB3 TG1
      在线出版日期: 2012年4月21日
      基金项目: 广东省教育部产学研项目