Role of disorder-order transformation in consolidation of ceramics

The ordering of stacking-disordered silicon carbide prepared from the elements by high energy ball milling was investigated during sintering. A sharp increase in density in the temperature region 1700-1800 degrees C was associated with a decrease in the disorder. Samples which had low disorder density showed a more continuous sintering behavior with temperature. Highly dense (up to 99% relative density) SiC can be obtained at 1900 degrees C under a pressure of 70 MPa with no hold time. Similar results were observed for structurally disordered carbon with 10 at% of boron. The sintering behavior exhibited an abrupt density increase in the narrow temperature region of 1450-1600 degrees C and was associated with disorder-order transformation. (c) 2006 Springer Science + Business Media, Inc.