Step Heating 

SHStep Heating – is an alternative technique for heating a component when applying thermography. In pulse thermography (PT – see last month’s What the Hec?!), a short pulse of heat is applied. In SH, a longer pulse, lasting from a few seconds up to a few minutes in length, is applied to the surface of a component. The temperature of the surface is monitored during the application of the SH, whilst the surface heats up and afterwards as the heat decays, to identify features and defects that modify the heat flow. The longer pulse duration allows the use of less powerful heat sources than are required for PT and it is possible to analyse larger areas.

SH is also called Time-Resolved Infrared Radiometry (TRIR), because the temperature is monitored over a longer period of time. SH is applied to assess coating thickness, to investigate the bond between a coating and a substrate and to inspect composite structures.

For more information on the experimental comparison of PT and SH see:

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