摘要
目的 :测试 GI- II型铝瓷专用代型材料烧结过程中的线膨胀性能 ,了解其在低温阶段烧结时与氧化铝底层材料的线膨胀匹配性。方法 :应用 Du Pont943热机械仪、Du Pont2 0 0 0热分析仪测试记录 GI- II型代型材料从室温到 70 0℃的热膨胀变化曲线 ,计算 2 0～ 2 0 0℃低温范围代型材料的线膨胀率并和氧化铝作对比。结果 :GI- II型铝瓷专用代型材料表现出低温阶段 (12 0℃以下 )的膨胀 ,膨胀量大于氧化铝底层 ,之后持续收缩的变化规律。结论 :氧化铝底层在烧结初期阶段受到张应力作用 ,烧结初期应缓慢升温让代型材料充分脱水。烧结后的代型材料有很大的体积收缩 ,可与铝瓷底层冠轻易分离。
Objective: To determine the thermal expansion of GI II die material compatible with slip casting glass infiltrated ceramic substructure,and to investigate the thermal expansion compatibility of the die material and the alumina in the early stage of alumina sintering firing. Mathods: The thermal expansion of GI II die material from room temperature to 700 ℃ was measured with DuPont 943 and DuPont 2000 thermal analyser,and the corresponding linear expansion ratio of alumina was calculated.Results: The die material showed higher expansion (0～0.126%) than the alumina (0～0.094%) under 145 ℃,which caused adverse tensile stress in the alumina substructure.At the temperature heigher than 145 ℃,the die material demonstrated continuous contraction which resulted in the seperation of the alumina from the die. Conclusion: In the early stage of alumina sintering firing,tensile stress will develop in the alumina,temperature should be increased slowly in order to dehydrate the die material. The die material may contract after sintering and can be seperated easily from aluminous ceramic base coping.
出处
《实用口腔医学杂志》
CSCD
北大核心
2000年第2期102-104,共3页
Journal of Practical Stomatology
基金
四川省卫生厅科学研究基金! 970 1 0 6
