The thermal emissivity of some materials used in thermionic valve manufacture

The laws governing thermal radiation are briefly reviewed and methods of measuring emissivity are described. The apparatus used by the author is described and an account of possible sources of error is given. Results of other workers are quoted wherever available, and the thermal emissivity over the useful working temperature range is given for the following materials. Metals Iron Molybdenum Nickel Tantalum Tungsten Gold Silver Platinum Alloys Nichrome Nimonic Moly-Tungsten Other Surfaces BaO-SrO on Nickel Carbonized Nickel Titania on Nickel Titania on Iron Aluminized Iron Titanium Hydride on Molybdenum Zirconium Preparations on Ni, Mo and Fe. Alumina Carbon