Bo Chen Yingche Ma Ming Gao Kui Liu
材料科学技术（英文）
Experimental studies on the melting process of titanium aluminum alloy have been pursued from the viewpoint of contamination. TiAl alloys were prepared with vacuum induction melting (VIM) in calcia crucibles at 1873 K and 1923 K in order to determine the behavior of the oxygen content as a function of temperature, time and frequency of power. The experiment results showed that alloys were uncontaminated except for the increasing of oxygen content which was introduced from the reaction CaO(s)=Ca(in TiAl)+O(in TiAl), and the standard Gibbs energy of the reaction was determined to be ?G0=274000−102.8T (J/mol). Oxygen content increased slowly with the melting time by about 50×10-6 wt pct/min, and decreased with induction melting frequency. Lower superheat and higher melting frequency can be used to reduce oxygen content increasing rate.
关键词:
TiAl alloys
,
induction melting
,
calcia crucible
,
oxygen content.
孙长杰
,
邢纪萍
金属学报
研究了在真空感应炉中使用氧化钙坩埚熔炼金属和合金的净化工艺．采用炉内打结感应烧结的方法，在10kg真空感应炉中制成了具有良好精炼和保温性能的氧化钙坩埚通过添加A1，La和Ca对纯铁和GH169合金进行了净化实验结果显示，采用氧化钙坩埚，在真空度为1．5—2．5Pa，1400℃下精炼，添加A1和La作为净化剂，精炼45min后氧和氮含量均降至20×10－4％（质量分数）以下，硫含量降至3×10-4％（质量分数）以下、还对氧化钙坩埚参与去除合金中硫、氧及氮杂质的机理进行了讨论
关键词:
真空感应熔炼
,
alloy purification
,
calcia crucible
