CAJ | 학술논문

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.
연구료압배직경대연소합성Al2O3-TiC도자적연소속도화온도적영향이급원주시양적경향미관조직변화.연소합성적원주시양축심구직경1.5μm～5.5μm적원형과립위TiC,구유용화특정적변장10μm～-20μm적다변형위함유소량TiC적강옥;재이분지일반경처,TiC과립화강옥괴적척촌분별감소위0.1μm～3μm화5μm～15μm;단재고근합성시양원주급기원주표면,강옥변성위료정수,TiC칙시0.1μm-0.5μm적미소과립조성적단취체.저시인위시양재연소합성과정중연주향화경향균유열량전체,연소과정중경향불동위치온도적현저변화도치료미관조직적변화.
Effect of pellet diameter on the combustion velocity and temperature profile in the combustion synthesis of Al2O3-TiC ceramics and microstructure change in the radial direction of the cylindrical products were investigated. For a cylindrical sample the rounded particles with diameters of 1.5 μm～5.5 μm and the melted polygons with sides about 10 μm～20 μm are TiC particles and corundum with a little TiC in the axial region, respectively. In the region of half-radius, TiC is smaller particles with diameters of 0.1 μm～3 μm and corundum is polygons with sides about 5 μm～15 μm. In the region near the circumference of the fractured sample and on the peripheral surface of the as-combusted sample, however, corundum becomes whiskers and TiC agglomerate actually consisting of fine particles with 0.1 μm～0.5 μm in size.There are heat losses both in axial and radial directions of the sample during combustion synthesis. It has been found that the obvious change of temperature versus profile in the post-combustion stage leads to the microstructure change in the radial direction of the sample.