精密铸造用氧化铝基复合陶瓷型芯

Alumina-Based Ceramic Core Nano-Composites for Investment Casting

利用原位合成方法制备了几种氧化铝基复合陶瓷型芯,讨论了MgO含量对氧化铝基复合型芯几种性能的影响。研究结果表明:随着MgO含量增加,陶瓷型芯气孔率先增加后减小;线膨胀系数先减小后增大;碱浸出速率减少。当MgO含量为1%(质量分数),经过1500℃烧结5h后型芯,蠕变量最小。通过实验分析,讨论了MgO含量对陶瓷型芯综合性能影响的机理。

A ceramic core using in the investment casting of metals sintered at 1300℃, 1400℃, and 1500℃ for 5 h were prepared by in situ synthesis method and the phases and microstructures were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. Effect of MgO content on the properties of ceramic core was discussed. The properties of these materials were studied. The results indicate that the microstructure of the core is characterized by the presence of MgO. The MgO content has an effect on the densification, creep deformation, crushability, and linear expansibility of alumina ceramic core. The ceramic cores containing MgO 1wt% sintered at 1500℃ for 5 h have the minimum creep deformation in the present research.