Materials outgassing rate decay in vacuum at isothermal conditions

Alvin Y. Huang; George N. Kastanas; Leonard Kramer; Carlos E. Soares; Ronald R. Mikatarian

doi:10.1117/12.2241212

27 September 2016 Materials outgassing rate decay in vacuum at isothermal conditions

Alvin Y. Huang, George N. Kastanas, Leonard Kramer, Carlos E. Soares, Ronald R. Mikatarian

Proceedings Volume 9952, Systems Contamination: Prediction, Control, and Performance 2016; 995206 (2016) https://doi.org/10.1117/12.2241212
Event: SPIE Optical Engineering + Applications, 2016, San Diego, California, United States

Abstract

As a laboratory for scientific research, the International Space Station has been in Low Earth Orbit for over 17 years and is planned to be on-orbit for another 10 years. The ISS has been maintaining a relatively pristine contamination environment for science payloads. Materials outgassing induced contamination is currently the dominant source for sensitive surfaces on ISS and modelling the outgassing rate decay over a 20 to 30 year period is challenging. Using ASTM E 1559 rate data, materials outgassing is described herein as a diffusion-reaction process with the interface playing a key role. The observation of -1/2 (diffusion) or non-integers (reaction limited) as rate decay exponents for common ISS materials indicate classical reaction kinetics is unsatisfactory in modelling materials outgassing. Nonrandomness of reactant concentrations at the interface is the source of this deviation from classical reaction kinetics. A t^-1/2 decay is adopted as the result of the correlation of the contaminant layer thicknesses and composition on returned ISS hardware, the existence of high outgassing silicone exhibiting near diffusion limited decay, the confirmation of nondepleted material after ten years in Low Earth Orbit, and a potential slowdown of long term materials outgassing kinetics due to silicone contaminants at the interface.

Citation Download Citation

Alvin Y. Huang, George N. Kastanas, Leonard Kramer, Carlos E. Soares, and Ronald R. Mikatarian "Materials outgassing rate decay in vacuum at isothermal conditions", Proc. SPIE 9952, Systems Contamination: Prediction, Control, and Performance 2016, 995206 (27 September 2016); https://doi.org/10.1117/12.2241212

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available