氢气辅助镁还原制备低氧氢化锆粉
Preparing ZrH2 powder by magnesiothermic reduction in hydrogen
董朝望 1段良洪 1刘汉宁 1郭学益 1夏阳2
作者信息
- 1. School of Metallurgy and Environment,Central South University,Changsha 410083,China;Hunan Key Laboratory of Nonferrous Metal Resources Recycling,Central South University,Changsha 410083,China;Hunan Engineering Research Center of Nonferrous Metal Resources Recycling,Changsha 410083,China
- 2. School of Metallurgy and Environment,Central South University,Changsha 410083,China
- 折叠
摘要
锆金属在核工业及能源领域发挥着重要的作用,但锆氧之间具有很强的亲和力,使锆金属难以经济有效地生产,粉末冶金方法制备锆金属可以实现锆金属的近净成形制备,锆粉可通过氢化锆粉脱氧制备而成.本文提出了一种在氢气辅助下镁还原制备高纯ZrH2粉末的新工艺,并分析了氢元素的强化脱氧作用.在750℃、240 min条件下Ar和H2气氛中镁还原制备的ZrH2粉末氧含量分别为3.05 wt%和1.03 wt%.对氢还原后的粉末进行脱氧,获得平均粒度为89.01 μm、氧含量为0.0047 wt%的氢化锆粉末.透射电镜测试结果表明,与氩气气氛还原粉末相比,氢气条件下的粉末表面钝化层厚度从8.51 nm减小到2.76 nm.热力学计算表明,H元素可以使Zr金属发生相变,降低Zr-O固溶体的稳定性,提高镁的脱氧能力.
Abstract
High-purity zirconium metal has been of rising significance to the nuclear and energy industry.However,zirconium exhibits a strong chemical affinity to oxygen,which causes high-purity zirconium metal to be difficult to produce cost-effectively.Powder metallurgy for preparing zirconium metal can achieve near net forming of zirconium metal.Zirconium powder can be prepared by deoxidation of zirconium hydride powder.In this study,an efficient process was proposed to prepare high-purity ZrH2 using magnesium powder as reducing agent in hydrogen atmosphere.A specific investigation was conducted on the effect of hydrogen on the magnesiothermic reduction and deoxidation of ZrO2.As indicated from the results,the oxygen content of the reduced powder in Ar was over three times that in H2 atmosphere at 750 °C for 240 min.Moreover,a passive oxide layer,with a thickness of～2.76 nm in H2 and of～8.51 nm in argon,was formed on the edge of the reduced powder.In accordance with thermodynamic calculation,hydrogen was found to be capable of destabilizing Zr-O solution.An ultra-high pure zirconium hydride powder containing＜350×10-6 oxygen and particle size of＜100 μm was prepared as assisted by hydrogen.
关键词
氢/镁还原/锆/粉末Key words
hydrogen/magnesiothermic reduction/zirconium/powder引用本文复制引用
基金项目
National Natural Science Foundation of China(52004342)
Innovationdriven Project of Central South University,China(150240015)
Natural Science Fund for Outstanding Young Scholar of Hunan Province,China(2021JJ20065)
出版年
2023
NETL
NSTL
维普
万方数据