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以γ-AlOOH和TiO_2为原料,添加不同质量分数SiC晶须(SiCw),采用无压反应烧结法制备多孔(Al_6Si_2O_(13)+TiC)/Al_2TiO_5复合材料,分析了SiCw质量分数对(Al_6Si_2O_(13)+TiC)/Al_2TiO_5复合材料孔隙率和抗压强度的影响,讨论了SiCw的强化机制。结果表明:不添加SiCw时,产物主要为Al_2TiO_5和少量Al_2O_3,还有少量未反应的TiO_2;加入SiCw之后,还形成了Al_6Si_2O_(13)和TiC相,TiC和Al_6Si_2O_(13)分别以规则颗粒状和晶须形态存在于Al_2TiO_5基体中。TiC颗粒与Al_6Si_2O_(13)晶须通过细化显微组织、裂纹偏转和晶须桥连机制,起到协同强化作用。SiCw的添加使孔隙率和抗压强度同时大幅度提高,随着SiCw质量分数的增加,(Al_6Si_2O_(13)+TiC)/Al_2TiO_5复合材料孔隙率降低,抗压强度提高的速率减小,当SiCw的质量分数为7.2%时,抗压强度最高,达到301.81 MPa。
(SiCw) with different mass fraction was prepared by using γ-AlOOH and TiO_2 as raw materials, porous (Al_6Si_2O_ (13) + TiC) / Al_2TiO_5 composites were prepared by pressureless reaction sintering. The effects of SiCw mass fraction on (Al_6Si_2O_ 13) + TiC) / Al_2TiO_5 composites, the strengthening mechanism of SiCw was discussed. The results show that the products are mainly Al 2 TiO 5 and a small amount of Al 2 O 3 and a small amount of unreacted TiO 2 without addition of SiCw. After adding SiCw, Al 6 Si 2 O 13 and TiC phases are also formed. TiC and Al 6 Si 2 O 3 (13) And whisker morphology exists in Al 2 TiO 5 matrix. TiC particles and Al_6Si_2O_ (13) whiskers play a synergistic effect by refining the microstructure, crack deflection and whisker bridging mechanism. With the addition of SiCw, the porosity and compressive strength were greatly increased at the same time. With the increase of SiCw mass fraction, the porosity of (Al 6 Si 2 O 13 + TiC) / Al 2 Ti 5 O 5 composites decreased and the rate of compressive strength decreased. The mass fraction of 7.2%, the highest compressive strength, reaching 301.81 MPa.