Heat resistance of palladium-plated molybdenum and antiemission properties of a palladium coating on molybdenum

To determine the physical mechanism of the action of a Pd coating, an x- ray-diffraction investigation of grids treated in experimental tubes was conducted. Unfiltered lambda CrK/sub alpha / radiation was used; the photographa were taken on a URS-60 apparatus, RKU-114M camera, D = 114.7 mm. On the x-ray diffraction picture, the lines of the intermetallic compound Pd/sub 2/ Ba are sufficiently clearly revealed. The opinion exists that the formation of such a compound under the conditions of operation of a tube with grid temperature 500 to 800 deg C is relatively improbable and is possible at 900 deg C. It is concluded that the anti-emission properties of Pd, like those of Au, are determined by its ability to bond Ba atoms into a stable intermetallic compound with a sufficiently high electron work function. (auth)