DEVELOPMENT OF ALUMINUM TITANATE CLAY COM POSITES FOR INFRARED RADIATOR

Sintered aluminum titanate has a very low thermal expansion and an inf rared radiative property selectively emitting large amounts of far inf rared rays. However, it is weak in mechanical strength. Spectral infra red emittance, thermal expansion coefficient, and mechanical strength of aluminum titanate-clay composites were studied to develop a materia l for infrared radiators. The composites containing 10 to 50 mass% cla y has low spectral emittance in the range of 5000 to 2500 cm(-1) and h igh emittance in the range of 1500 to 360 cm(-1). The bending strength of the composite increased with increasing clay content. The composit e with a clay content of 30 mass% formed by hand pressing using a plas ter mold and fired at 1500 degrees C had a large strength for infrared radiators; 80 MPa. The average linear thermal expansion coefficient f rom room temperature to 800 degrees C of the 30 mass% clay-containing composite fired at 1500 degrees C was lower than 2.5 x 10(-6)/degrees C.