Infrared heating and cooling system aids thermal endurance testing rig

A purpose-built heating and cooling system from Heraeus Noblelight is an essential element of a thermal endurance rig used by BAE Systems’ Advanced Technology Solutions team based at Towcester to test a range of materials under extreme conditions. Heating is achieved through 12 2kW fast response medium-wave emitters and cooling is by means of a cooling module with a cooling fan.

The BAE Systems Towcester site is a centre for microwave material design and manufacture, specialising in producing low observable materials and materials designed to reduce electromagnetic interference effects from radar systems. As part of this function it is important to have an understanding of how the materials used perform in the working environment including at elevated temperatures for prolonged periods of time.

Traditional ovens and environmental cabinets provide uniform thermal exposure to specimens which are not necessarily representative of the working environment that the materials will operate in. A need was therefore identified for a piece of equipment that would enable materials to be exposed to more representative ‘through thickness thermal gradients’ for extended periods of time.

To this end, Heraeus worked with BAE Systems personnel to design and manufacture a simultaneous heating and cooling system capable of trialling material samples. This consists of a free-standing stainless steel cabinet, which features a 24kW fast response medium wave infrared module in the top section to direct controlled heat onto the top surface of the sample, a sliding table in the middle section to allow easy loading and unloading of samples, and a cooling module to direct cool air onto the bottom surface of the sample via a series of nozzles. Although it has a manual option, the heater module is predominantly run in automatic mode for many hours and the 12 2kW are regulated automatically to achieve the temperature required on the sample surface, as monitored by a pyrometer. A pyrometer also measures the temperature of the bottom surface of the sample, which is then controlled by regulating the airflow.

“The Heraeus system has provided a simple solution to what could have been a difficult challenge and, moreover, it is very easy to use,” said Cathy Evans, Materials Scientist at BAE Systems.