Studies on Cordierite-Mullite Refractories: Part-1 : Effect of Talc

摘要

The effects of progressive incorporation of talcum powder in conventional refractory body mix having 60 percent china clay and 40 percent grog have been studied. The specimens were fired at different test temperatures ranging from 1200 deg to 1400 deg C with 2 h dwelling time at the respective peak temperatures. The addition of talc reduced the percent thermal expansion significantly as well as enhanced the thermo-mechanical strength. The results also revealed that the fired strength of the developed body increased from 169.40 kg.cm~(-2) to 288.5 kg.cm~(-2). The gradual reduction in the percent thermal expansion values of the talc containing bodies was attributed to the presence of cordierite and mullite phases in the compositions. The thermal shock resistance of the body mix containing 20 wt percent talc was found to be about 2.5 times higher than that of the standard body mix fired at 1400 deg C. The developed refractory kiln furniture also provided useful service life at a working temperature of 1250 deg C bone china factory.