Modification of CaO Refractory for Melting Titanium Alloys and Its Hydration Resistance
CaO is a promising refractory for melting TiNi shape memory alloys,the carbon contamination can be avoid by using CaO crucible instead of carbon crucible. However. its industrial application is limited by the easy hydration of CaO in the air. In this study,the hydration resistance of CaO is modified by the addition of ZrO2,the powder of CaO adding 6.0 to 15.0mol％ ZrO2 and 2.0mol％ TiO2 is ball milled,the mixture is shaped into the chip by the isostatic pressing method (IP),then the samples are sintered at 1750℃. The X-ray diffraction analysis reveals that the sintered samples consist of CaO dissolved with ZrO2 and CaZrO3. The anti-hydration property is described by the weight addition of samples,which are stored at the room temperature and atmosphere. It is shown that the sample with 12％ ZrO2 of additive possesses the good hydration resistance,its weight addition stored afier 56-days is less than 0.6wt％. Therefore,the powder of CaO with 12.0％ ZrO2 additive are used to prepare the crucible by IP,the green crucible is sintered at 1750℃. This home-made crucible is used for melting TiNi alloy by means of the induction method at 1 500~1 800℃ temperature and the vacuum environment,it is found that, the intemal and external surface of crucible were almost kept unchanged after melting,this refractory did not obviously react with titanium melts,this result may provide a support for searching a new refractory with the good hydration resistance for melting of titanium alloys.
CaO refractory TiNi alloy Hydration resistance Crucible
Sun Tingting Jiang Min LI Chonghe Lu Xionggang Liu Weidong
Shanghai Key Laboratory of Modern Metallurgy & Materials Processing,Shanghai University Shanghai 200072,China
国际会议
Frist Annual Meeting on Testing and Evaluation of Inorganic Materials(第一届全国无机材料测试与评价学术年会)
南昌
英文
502-505
2010-04-28（万方平台首次上网日期，不代表论文的发表时间）