Title :
Small-Scale Simulation Chamber for Space Environment Survivability Testing
Author :
Johnson, Robert H. ; Montierth, Lisa D. ; Dennison, J.R. ; Dyer, Justin S ; Lindstrom, Ethan R.
Author_Institution :
Phys. Dept., Utah State Univ., Logan, UT, USA
Abstract :
A vacuum chamber was designed that simulates the space environment to facilitate tests of material modification due to space environment interactions. Critical environmental elements to be simulated include an ultrahigh vacuum, a far ultraviolet (FUV)/ultraviolet/VIS/NIR solar spectrum, an electron plasma flux, temperature extremes, and long duration exposure. To simulate the solar electromagnetic spectrum (EMS), a solar simulator was used with a range 200-2000 nm. A Krypton lamp provides surrogate radiation for the prominent FUV hydrogen Lyman- α120-nm emission not produced by the solar simulator. A monoenergetic electron flood gun (20-15 keV) provides a controlled electron flux. Electron and EMS incident fluxes of up to four times sun equivalent intensities at 95% uniformity across the full 100- cm2 sample surface are possible to reduce the exposure time for accelerated testing. A temperature range from 100 to 450 K is achieved using an attached cryogenic reservoir and resistance heaters. The versatile sample holder and radiation mask allow for cost-effective, customizable investigations of multiple small-scale samples under diverse conditions. In situ monitoring capabilities allow measurements to be taken at frequent intervals during the course of the exposure cycle, while the samples are still under vacuum. An automated data acquisition system monitors and records the temperature, pressure, electron, and EMS fluxes. Calibrated reflectivity, absorptivity, and emissivity of the samples can be measured using in situ integrating sphere and IR absorptivity/emissivity probes.
Keywords :
aerospace materials; calibration; cryogenics; data acquisition; discharge lamps; electromagnetic wave absorption; electron guns; emissivity; infrared spectra; krypton; magnetic flux; materials testing; reflectivity; resistance heating; sample holders; solar spectra; ultraviolet spectra; visible spectra; EMS flux; EMS simulation; FUV solar spectrum; IR absorptivity probe; IR emissivity probe; Krypton lamp; NIR solar spectrum; VIS solar spectrum; absorptivity calibration; automated data acquisition system; controlled electron flux; cryogenic reservoir; electron plasma flux; electron volt energy 20 keV to 15 keV; emissivity calibration; exposure reduction; far ultraviolet; in situ monitoring; material modification test; monoenergetic electron flood gun; pressure flux; radiation mask; reflectivity calibration; resistance heater; small-scale simulation chamber; solar electromagnetic spectrum; solar simulator; space environment interaction; space environment simulation; space environment survivability testing; sun equivalent intensity; surrogate radiation; temperature 100 K to 400 K; temperature extreme; temperature flux; vacuum chamber; versatile sample holder; wavelength 200 nm to 2000 nm; Aircraft manufacture; Materials; Monitoring; Plasma temperature; Space vehicles; Temperature measurement; Temperature sensors; Electromagnetic flux; electron flux; instrumentation; materials testing; space environment interactions;
Journal_Title :
Plasma Science, IEEE Transactions on
DOI :
10.1109/TPS.2013.2281399