Arthur W. Moore

Thermal diffusivity and thermal conductivity of pyrolytic graphite from 300 to 2700° K

Abstract The thermal diffusivity and thermal conductivity of as-deposited, annealed, and stress-annealed pyrolytic graphite have been measured at room temperature and over the range 1500–2700°K. Values of the thermal conductivity parallel to the plane of deposition compare reasonably well with published results on similar materials, as do the values in the perpendicular direction at room temperature. The conductivity in the perpendicular direction for the annealed and stress-annealed materials is the first reported for such highly oriented materials at temperatures above 900°K, and they follow approximately a T−n dependence with n ⩽ 1 2 over the temperature range 1500–2700°K, where the conductivity is two-to-three times larger than expected from a T−1 extrapolation from room temperature.

Degradation of thin films: comparison between low Earth orbit experiments and laboratory simulations of the space environment

Abstract The low Earth orbit (LEO) environment exposes spacecraft materials to atomic oxygen, UV light, meteroid impact and thermal cycling. The purpose of this paper is to report on progress towards evaluating damage done to candidate space materials, and ways to protect materials on future long-term space missions in LEO. Specifically, we prepared and characterized sets of samples for flights on the US Space Shuttle missions STS-46 and STS-51, and evaluated samples returned from STS-46. In addition, laboratory simulations of the LEO environment are shown to present interesting problems and challenges.