Le. Murr et al., ELECTRON-MICROSCOPE OBSERVATIONS OF IMPACT CRATER DEBRIS AMONGST CONTAMINATING PARTICULATES ON MATERIALS SURFACES EXPOSED IN-SPACE IN LOW-EARTH-ORBIT, Journal of Materials Science, 28(17), 1993, pp. 4553-4561
Debris particles extracted from a small sampling region on the leading
edge of the Long Duration Exposure Facility (LDEF) spacecraft have be
en examined by analytical transmission electron microscopy and the ele
mental frequency observed by energy-dispersive X-ray spectrometry and
compared with upper atmosphere (Earth) particle elemental frequency an
d the average elemental compositions of interplanetary dust particles.
A much broader elemental distribution was observed for the exposed sp
acecraft surface debris milieu. Numerous metal microfragment analyses,
particularly aluminium and stainless steel, were compared with scanni
ng electron microscope observations of impact crater features, and the
corresponding elemental spectra on selected LDEF aluminium tray clamp
s and stainless steel bolts. The compositions and melt features for th
ese impact craters and ejecta have been shown to be consistent with mi
crocrystalline debris fragments in the case of aluminium, and these ob
servations suggest an ever changing debris milieu on exposed surfaces
for space craft and space system materials.