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以Ti,Al,Al2O3为初始粉料,通过750～800℃氮气保护下的中温焙烧,然后在1420～1550℃在氮气氛下反应烧结,制备了不同配比的(AlN,TiN)-Al2O3复合材料。研究了组成及烧结工艺对复合材料力学性能、显微结构等的影响。用XRD,SEM等方法分析粉体及烧结体的相组成及微观结构。分析结果表明:AlN,TiN的形成,有助于材料的致密化并使其力学性能提高。组成为20wt%(Al,Ti)-Al2O3的粉体在1520℃、30MPa、保温、保压30min热压烧结条件下,与N2气反应可得到硬度(HRA)为94.1的高硬度的(AlN,TiN)-Al2O3复合材料,该材料的抗弯强度为687MPa,断裂韧性(KIC)为6.5MPa·m1/2。
Ti, Al and Al 2 O 3 as the initial powders were calcined at a temperature of 750-800 ℃ under nitrogen atmosphere and then sintered at 1420-1550 ℃ in a nitrogen atmosphere to prepare (AlN, TiN) -Al 2 O 3 composite material. The effects of composition and sintering process on the mechanical properties and microstructure of the composites were studied. The phase composition and microstructure of the powders and sintered bodies were analyzed by XRD and SEM. The results show that the formation of AlN and TiN contributes to the densification of the material and its mechanical properties. The powders with the composition of 20wt% (Al, Ti) -Al2O3 can react with N 2 gas under high pressure sintering conditions of 1520 ℃, 30MPa, holding temperature and holding pressure for 30min to obtain high hardness (AlN, TiN) -Al2O3 composites. The flexural strength and fracture toughness (KIC) of this material are 687MPa and 6.5MPa · m1 / 2, respectively.