A method for manufacturing an x-ray tube bearing cage includes the step of forming a bearing cage from a carbon-carbon composite material. A coating is applied to the carbon-carbon composite bearing cage. The coating includes an outer layer formed of a dry film lubricant. The coated carbon-carbon composite bearing cage is included in a bearing assembly in the x-ray tube and forms a lubricious enclosure for bearing balls positioned therein to minimize wear and heat generation in the bearing assembly.