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Ｂ４Ｃ基体中掺加不同含量的Ａｌ２Ｏ３在１８５０℃，３５ＭＰａ压力下，热压烧结，利用ＸＲＤ、ＳＥＭ、ＥＤＡＸ、ＳＥＮＢ等方法对试样的组织结构及力学性能进行研究。结果表明：Ａｌ２Ｏ３掺加不仅降低了热压烧结温度，促进了烧结致密化，获得９６％以上的相对密度，而且提高了纯Ｂ４Ｃ材料的力学性能。Ｂ４Ｃ－２０％ｖｏｌＡｌ２Ｏ３的ＫＩＣ值达５．４３ＭＰａ·ｍ１／２，弯曲强度为３７０．４ＭＰａ；Ｂ４Ｃ－３０％ｖｏｌＡｌ２Ｏ３的ＫＩＣ值达５．７６ＭＰａ·ｍ１／２，弯曲强度为３８９．５ＭＰａ。分析认为；较高致密度是提高强度的主要原因，强韧化机制是颗粒细化、微裂纹及残余应力场共同作用的结果。
B4C matrix doped with different content of Al2O3 at 1850 ℃, 35MPa pressure, hot-pressed sintering, the use of XRD, SEM, EDAX, SENB and other methods to study the microstructure and mechanical properties of the sample. The results show that the addition of Al2O3 not only reduces the hot pressing temperature, promotes the densification of sintering, and obtains the relative density of over 96%, but also improves the mechanical properties of the pure B4C material. The KIC value of B4C-20% vol Al2O3 is 5.43MPa · m1 / 2, the flexural strength is 370.4MPa; the KIC value of B4C-30% volAl2O3 is 5.76MPa · m1 / 2 and the flexural strength is 389.5MPa. The analysis shows that the higher density is the main reason to increase the strength. The toughening mechanism is the result of the combination of grain refinement, micro-cracks and residual stress field.