【摘要】 凝胶注模成型工艺是一种重要的原位凝固成型技术 ,它能有效地提高材料的可靠性以及降低复杂形状陶瓷部件的制造成本。本工作在 Si3N4陶瓷凝胶注模成型工艺的基础上 ,对 90 wt%α- Si3N4+ 7.5 wt% Y2 0 3+ 2 .5 wt% Al2 0 3体系进行了二步气压烧结。得到的陶瓷其抗弯强度为 95 8± 41.8MPa,断裂韧性为 9.6 MPa·m1 / 2 ,韦伯模数为 2 3。得到的 Si3N4陶瓷的显微结构是由部分大的长柱状晶粒分布在较细晶粒组成的基体上形成了所谓的双峰分布更多还原

【Abstract】 The forming process of gelcasting is one of the important in situ forming techniques, which can effectively increase materials reliability and lower the manufacturing costs of complex shaped ceramic parts Based on gelcasting of Si 3N 4, Two step gas pressure sintering of Si 3N 4 is made in this paper Their room temperature bending strength can reach 958±41 8MPa,fracture toughness can reach 9 6MPa·m 1/2 ,Weibull modulus can reach 23 Si 3N 4 ceramics obtained exhibits a bimodal microstructure composed of large elongated grains dispersed in a fined grained matrix更多还原