The effect of aggregate shape and its aspect ratio on the R-Curve behavior of a refractory castable

The microstructure of refractory materials either bricks or monolithics, is the single most important factor determining the material's fracture behavior. In this sense, the morphology, the aspect ratio of the coarse particles, as well as the characteristics of the matrix/aggregate interface, can be responsible for the crack arresting ability of the microstructure. In this work it was investigated the effect of morphology (sphere, rosette, cylinder) and the aspect ratio (1, 2, 4) of the coarse refractory aggregate (> 2 mm), as well as the adhesion state between matrix and the coarse aggregate, on the R-Curve behavior of a refractory castable, determined by means of the "Two Parameters Technique".