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A silicon carbide disk was sintered from 2090" to 2190°C in 25°C steps. After each sintering step, the disk was examined using a precision acoustic scanning system to determine acoustic attenuation and velocity. The bulk density was found to vary nonmonotonically with sintering temperature. The density varied as much as 10% from its value at 2090°C during the sintering process. Local density fluctuations occurred in an organized and history-dependent way. These local density fluctuations varied up to ?7% of the bulk density and were made visible by acoustic attenuation and velocity mapping. [Key words: silicon carbide, sintering, density, porosity, ultrasonics imaging.] ERAMIC processing is being investiCgated extensively by an international effort. A major goal of current processing research is to control the amount, size, uniformity, and distribution of porosity in ceramics. Considerable effort is being made to control porosity variations by modifying the ceramic powder processing that is done to form green or unsintered ceramics. Milling techniques, powder-size distributions, binders, pressing pressures, etc., all have an effect on the final poresize distribution of a sintered ceramic. There are relationships between the type of powder processing and the final microstructure of the sintered ceramic. '** We will show that there exist large local density fluctuations that occur within the bulk ceramic during sintering. These local density variations are historydependent and can be tracked or followed during the sintering process.