Thermal Shock Testing
The two higher ranges require the use of a perfluorocarbon fluid with a low freezing point and high boiling point. ORS uses a proprietary solution which has a useful range of –97 to 175°C, in both hot and cold tanks. The basket, which holds the parts being tested, switches from one tank to the other in eight seconds. It returns to the load/unload position automatically after the specified number of cycles.
Air-to-air thermal shock testing is used for parts that cannot be immersed in liquid or when slower rates of change are appropriate. Air-to-air testing modifies the temperature cycle by convection, a considerably slower heat exchange process than by conduction.
In both thermal shock test procedures, transition times (hot-cold and cold-hot) are typically the same, usually less than 10 seconds.