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The paper describes the factors which must be considered when assessing the suitability of a material for a rotary regenerator disc which runs at 1850°F. Mechanical and thermal stressing, thermal stability, and corrosion resistance are analyzed, using the properties of type CPD-5 material. This is a new lithium-alumino-silicate glass ceramic developed by Corning Glass Works. The environmental conditions assumed are those found in the 2500°F turbine inlet temperature engine which is being developed by the Ford Motor Company.

The effects of cell geometry and dimensions on the thermal shock resistance of catalytic monoliths is examined analytically. Two cell geometries, namely square and equilateral triangle, are considered. Thermal gradients predicted by theory compare well with the experimental results. It is found that for equivalent thermal shock resistance the triangular cell requires lower coefficient of thermal expansion than the square cell. Also, as the cell density is increased for higher geometric surface area, both geometries require a reduction in thermal expansion coefficient to preserve their thermal shock resistance. The above comparison does not take into account some of the other considerations which affect the overall performance, such as manufacturing advantage and the conversion efficiency. Also, the triangular cell examined has a cell density of 236/in2 with 20% greater geometric surface area than the square cell with a cell density of 200/in2.

This paper focuses on the effect of temperature on biaxial strength of curved, symmetrically laminated, automotive windshields. In view of their aspheric curvature, the measurement of biaxial strength requires a special ring-on-ring test fixture with compliant loading and support rings. The key factors that affect strength are (i) fatigue behavior of surface flaws, (ii) expansion mismatch between glass and PVB interlayer, and (iii) interfacial bond integrity. These, in turn, depend on the operating temperature which for automotive windshields can range from −40°C in winter to +50°C in summer. The data show that the biaxial strength is 21% higher at −40°C and 28% lower at +50°C than that at room temperature. An assessment of fatigue and interfacial bond integrity shows that strength changes of these magnitudes are predominantly caused by residual stresses arising from expansion mismatch between glass and PVB interlayer.

Thin wall ceramic catalysts offer improved performance by way of faster light-off, lower back pressure and higher FTP efficiency than standard ceramic catalysts. These advantages are attributed to their lower thermal mass, larger open frontal area and higher geometric surface area. This paper will focus on their physical durability, notably their thermal shock resistance. The critical physical properties which influence thermal shock resistance - namely modulus of rupture, elastic modulus and coefficient of thermal expansion - will be examined over a wide range of operating temperatures for both standard (400/6.5) and thin wall catalyst supports (600/4.3 and 400/4.5) with stable high temperature washcoat systems. These data help evaluate the thermal shock capability of each system via computation of thermal shock parameter. The validity of such computations is tested against the thermal shock data from oven test.