Because the properties of the hexagonal boron nitride particles are much different from those of the yttria powders,resulting in some problems in process of preparing the hBN shell mould.

• 在型壳制备过程中除了使用氮化硼作为面层造型材料外,用钇溶胶作为粘结剂,同时通过加入少量的氧化钇来改善氮化硼基复合型壳的性能。