The surface temperature of the test specimen in a xenon lamp aging tester cannot be accurately determined because the surface temperature of the exposed material depends mainly on radiation absorption, radiation emission, heat conduction within the test specimen, and heat transfer between the test specimen and the air or with the specimen holder. Since it is not practical enough to detect the temperature of individual test specimens, specific black plates are used as temperature sensing parts for determining and controlling the temperature. The following Corsaid instrumentation to introduce: xenon lamp aging test chamber black plate temperature introduction.
Black plate temperature: choose the following two black plate temperature used as a reference for exposure testing: 63 degrees Shi 2 degrees or 100 degrees soil 2 degrees.
The essential difference between the black plate thermometer and the black standard thermometer is the adiabatic base of the black plate. The surface temperature of light-colored or thermally conductive specimens is generally lower than the temperature displayed by the black standard thermometer, so the black standard thermometer displays the temperature of the exposed surface of dark-colored specimens with poor thermal conductivity. Different models of black plate thermometer and black standard thermometer for different models of xenon lamp aging tester.
Note: The higher temperature is for special tests, which may make the specimen more susceptible to pyrolysis and affect the test results.
If using water spray, the temperature should be kept constant during the water-free cycle. If the thermometer can not reach the specified temperature, the highest temperature reached during the water-free period should be stated in the test report. The black standard thermometer shall be measured in a continuous manner even if the exposure device works in an alternating manner.
The black standard or black plate temperature is also affected by the ambient air temperature and wind speed. Under low irradiance conditions, the difference between the temperature displayed by the black plate thermometer or black standard thermometer and the true temperature of the specimen is small.
Xenon lamp aging test chamber spraying cycle: the test used in the spraying cycle can be selected from the following spraying cycle Each spraying time: 18min plus or minus 0.5min
Two times the sound of water spraying water-free time: 102min plus or minus 0.5min
Relative humidity of the xenon aging tester: the relative humidity used in the test should be agreed upon by the relevant parties, but it is best to choose any of the following conditions: (50 Shi5)% or (65 Shi5)% Note: Because the temperature of different colors and thickness of the specimen is different, so the relative humidity measured in the test chamber is not necessarily equal to the relative temperature of the air adjacent to the test surface.