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研究了压坯直径对燃烧合成Al2O3－TiC陶瓷的燃烧速度和温度的影响以及圆柱试样的径向微观组织变化。燃烧合成的圆柱试样轴心区直径1．5μm～5.5μm的圆形颗粒为TiC，具有熔化特征的边长10μm～20μm的多边形为含有少量TiC的刚玉；在二分之一半径处，TiC颗粒和刚玉块的尺寸分别减小为0．1μm～3μm和5μm～15μm；但在靠近合成试样圆周及其圆柱表面，刚玉变成为了晶须，TiC则是0．1μm－0．5μm的微小颗粒组成的团聚体。这是因为试样在燃烧合成过程中沿周向和径向均有热量传递，燃烧过程中径向不同位置温度的显著变化导致了微观组织的变化。
The effects of green compact diameter on the combustion rate and temperature of the Al2O3-TiC ceramics synthesized by combustion and the radial microstructure changes of the cylindrical samples were investigated. The round particles with the diameter of 1.5μm ~ 5.5μm in the axial region of the combustion synthesized cylindrical sample are TiC, the polygons with melting edge with the length of 10μm ~ 20μm are corundum containing a small amount of TiC; at the half radius, TiC The size of the particles and the corundum blocks were reduced to 0.1μm ~ 3μm and 5μm ~ 15μm, respectively; however, the corundum became whisker near the circumference of the composite sample and its cylindrical surface, and TiC was 0.1μm-0.5μm Small particles composed of aggregates. This is because the sample has heat transfer both in the circumferential direction and in the radial direction during the combustion and synthesis process. The significant changes in the temperature at different radial positions during combustion lead to the changes of the microstructure.