Transient temperature measurement of electron beam bombarded stainless steel via nanosecond two-color pyrometry

A two-color pyrometer is presented that enables detection of a temperature rise with temporal resolution of 17.5 ns. It is geared toward extreme environments where fast electrical electron pulses or currents may push the temperature of a metal surface to melt on a 100 ns time scale. The developed pyrometer, which utilizes an internal gain of 100x, has been tested for SS304 surfaces subjected to an intense electron beam in vacuum. The two-color pyrometer is calibrated using a quasi-calibration method by heating a graphite disk and measuring this temperature with a FLIR TG297 thermal camera. The quasi-calibration method supports the pyrometer to be within 3% accuracy of absolute temperature. The measured temporal temperature profile of the SS304 surface was derived from the pyrometer output data through a detailed gray-body analysis utilizing empirical emissivity data from publicly available literature.