The emissivity of carbon steel for infrared (IR) thermometer use is approximately 0.3, which can significantly affect measurement accuracy when using a thermometer with a fixed emissivity of 0.95. According to OMEGA's emissivity tables, values for steel can range from 0.07 to 0.91, influenced by factors such as temperature, surface finish, and oxidation. Users are advised to experimentally measure the specific properties of their carbon steel sample or refer to a temperature-dependent emissivity table for precise applications. Engineering decisions should be made based on the desired heat transfer characteristics, utilizing higher emissivity for minimized heat transfer and lower emissivity for maximized heat transfer.
PREREQUISITESEngineers, materials scientists, and technicians involved in temperature measurement and thermal analysis using IR thermometers, particularly those working with carbon steel and similar materials.
middlj said:Approximately 0.3
Mech_Engineer said:OMEGA has a large table of emissivity values for common materials. You can start there, and maybe use a scaling factor to correct for the incorrect emissivity assumption of the thermometer. Problem is, emissivity varies strongly as a function of tempertuare, surface finish, oxidation, etc. Based on the fact that Omega's table shows Steel can vary anywhere from 0.07-0.91, I think you're going to need to measure you specific sample's properties experimentally, or get a solid temperature-dependent published table of values for your specific material and surface finish.
http://www.omega.com/literature/transactions/volume1/emissivitya.html