Insulation aging in pure oxygen and in a vacuum

OXIDATION AND EVAPORATION are two of the mechanisms by which insulation deterioration have been described. The present tests were made with the idea of showing their relative effects and to study the possibility of acceleration of these effects to give more rapid evaluation of various materials. The materials investigated are black varnished cloth, phenolic impregnated kraft paper, and silicone rubber on glass cloth. These are aged in some or all of the mediums of oxygen, nitrogen, air, and a vacuum. These data are compared with previous data on these and similar materials aged in air and nitrogen.