METHOD OF PREPARING RIGID MULLITE-WHISKER FELT

摘要

is a process in which (1) the shape of powder of sio2 or al2o3 alf3 and for obtaining a body of the desired configuration and dimensions; (2) heating the body at a temperature of 700 degrees thought and level in an atmosphere of dry (sif4) to form the rate of topaz in the form of a bar (3); and then heating the body in a dry atmosphere, thought of sif4 toa temperature range of about 1150u00b0c and 1700u00b0c topaz crystal for converting in the shape of a bar of acicular crystalline mullite whiskers which form a rigid porous structure and mechanisms. the marker has the same configuration as the main body thought with a modification of the linear dimensions of the order of 1.5 percent.the pen is used as a preform for ceramic matrix composites and metal matrix, or only as a heat insulator.