【摘要】 针对石墨坩埚熔炼TiFe合金增碳的缺点,对三高石墨坩埚和CaZrO3坩埚真空感应熔炼TiFe基储氢合金进行了对比研究.用ICP原子发射光谱仪分析合金的化学成分,并用Leca金相显微镜、SEM、XRD分析其金相组织、表面形貌、微区元素分布和物相结构,测定了合金的吸放氢PCT曲线.结果表明,两种坩埚熔炼TiFe合金的氧含量相当且未见增碳,但三高石墨坩埚熔炼合金的碳含量为0.220%(ω),超过0.1%(ω)的技术要求;其次CaZrO3坩埚熔炼合金具有枝晶组织,而后者熔炼合金则由层片状结构的等轴晶组织和沿晶界或在晶粒内分布的球形TiC颗粒构成;经CaZrO3坩埚和三高石墨坩埚熔炼合金的最大吸氢量分别为1.823%(ω)和1.832%(ω),即CaZrO3坩埚可代替三高石墨坩埚熔炼制备TiFe储氢合金.更多还原

【Abstract】 The carbon contamination of alloys melted by electro graphite crucible is impossible to endure owning to an inherit reaction between the melt and carbon. The TiFe-based alloy is prepared by vacuum induction melting (VIM) with CaZrO3 and electro graphite crucibles. The prepared samples are examined by optical microscope, SEM, XRD and EDS, and their PCT curves measured. The results show that the oxygen content of alloy by melted CaZrO3 crucible is almost equal to that by the graphite one, but without the carbon contamination, meanwhile the carbon content of alloy obtained by the latter is 0.220%(ω), which exceeds the tolerance of commercial alloy [0.1%(ω)]. The microstructure of alloy melted by CaZrO3 crucible is dendrite, but that by the graphite crucible is composed of the equiaxed crystal with lamellar structure and spherical TiC particles distributed along grain boundaries or within the grains. The maximum hydrogen absorption capacity of alloys melted by both crucibles is 1.832%(ω) and 1.823%(ω), respectively. The TiFe based hydrogen storage alloys can be produced by VIM with CaZrO3 crucible in place of electro graphite crucible.更多还原