Characterization of the hot-cutting defects produced by the processing of alumina green tape

In this paper, the hot cutting surface and edge formed at green state are characterized and researched. Surface morphology of the hot-cutting green state and co-fired state is observed by optical microscope and SEM, and compared with that of the natural surface that formed in tape casting. The Weibull statistical strength test is introduced to evaluate the influence to the quality and reliability and the fractography is examined and analysed by optical microscope and SEM. Comparing the hot-cutting surface and edge before and after co-firing shows the great similarity with each other, which indicate the firing process can't cure the damage occurred in hot-cutting process, while the comparing between the hot-cutting surface and natural surface shows the hot-cutting surface is not only much coarser, but also with ravine-like defect on the surface and defect scraggly-like at the edge. The Weibull statistical strength test reveals the two-kinds of defect leads to a remarkable decrease in strength and also a increasing variability, which means a lower reliability compared to the natural surface. The fractography analysis shows the ravine-like defect introduced at the edge is more dangerous than the defect on the surface and the natural defect inside the volume.