论文部分内容阅读
本论文利用商用γ-Al2O3粉体和上海硅酸盐所制备的碳化硅晶须，通过热压工艺来制备碳化硅晶须补强氧化铝复合材料．当晶须含量为30vol％时，室温下复合材料的抗弯强度为812±38MPa，断裂韧性为8．8±0．1MPa·m1／2；在1200℃、Ar气氛下，分别为560±61MPa和6．1±0．4MPam1／2．在氮气氛下，由于晶须的损伤易导致材料的力学性能下降．添加剂可降低复合材料的烧结温度，但不利于其力学性能．显微结构观察发现，不同温度下，AS复合材料的增韧机理有变化．
In this thesis, silicon carbide whisker reinforced by commercial γ-Al2O3 powder and Shanghai silicate was prepared by hot pressing process to prepare silicon carbide whisker reinforced alumina composite material. When the whisker content is 30vol%, the flexural strength of the composites at room temperature is 812 ± 38MPa and the fracture toughness is 8.8 ± 0.1MPa · m1 / 2. At the temperature of 1200 ℃ and Ar atmosphere, the flexural strength is 560 ± 61MPa And 6.1 ± 0.4 MPam1 / 2. In a nitrogen atmosphere, the mechanical properties of the material tend to decrease due to whisker damage. Additives can reduce the sintering temperature of the composite, but not conducive to its mechanical properties. The microstructure observation showed that under different temperatures, the toughening mechanism of AS composites changed.