The guarded hot-plate method

The guarded hot plate method measures the heat flux and associated test conditions for a flat laminate. The surfaces of the laminate are in contact with parallel platens held at constant temperature. The guarded-hot-plate provides the power for the measurement and defines the actual test volume being measured and reduces heat flow laterally. The measurements are made under vacuum conditions ensuring good thermal contact between the hot and cold assemblies and the specimen surfaces. This is assisted by using springs to maintain a constant pressure. Once steady state conditions are reached, the unidirectional heat flow Q is measured.