Thermal shock without

The design of the pressure vessel should be such that it can withstand pressurized thermal shocks without incurring a failure of integrity. 

Silicon carbide has very high thermal conductivity and can withstand thermal shock cycling without damage. It also is an electrical conductor and is used for electrical heating elements. Other carbides have relatively poor oxidation resistance. Under neutral or reducing conditions, several carbides have potential usehilness as technical ceramics in aerospace appHcation, eg, the carbides (qv) of B, Nb, Hf, Ta, Zr, Ti, V, Mo, and Cr. Ba, Be, Ca, and Sr carbides are hydrolyzed by water vapor. 

Hybrid resins have been used to improve the flexibility, thermal shock resistance, elongation, heat distortion temperature, and impact strength of unmodified epoxy adhesives. However, there can also be some sacrifice in certain physical properties due to the characteristics of the additive. These alloys result in a balance of properties, and they almost never result in the combination of only the beneficial properties from each component without carrying along some of their downside. 

The thermal shock resistance is a measure of the temperature range through which glass vessels, of normal waU-thickness, may be suddenly cooled without breakage. 

Epoxy systems with flexibihsers and properly-selected fillers exhibit high resistance to rapid changes in temperature and do not show signs of cracking or shattering. Rigid epoxy systems can cause severe problems. Better formulated systems can withstand repeated thermal shock cycles from 180°C to -75°C without failure. 

Thermal shock resistance. Cured coating or adhesive can withstand, without fracturing, the expansion and contraction movements encountered during thermal cycling. A correctly formulated system can withstand the effects of thermal cycling over a wide temperature range, from -55°C to 85°C. 

Low Coefficient of Thermal Expansion—A low coefficient of thermal expansion of 1.6 X 10 /°F allows the block to withstand the wide range of temperatures without spalling. It is resistant to upset or bypass operations where thermal shock can damage or destroy other lining materials and the insulation it provides protects the support structure itself from such damage. 

At low temperatures, the thermal properties participate in the so-called thermal resistance, i.e. resistance to thermal shock it is expressed by the maximum diflerence of temperatures which a glass object can withstand without fracture when cooled abruptly in a defined way. 

---