Why is Materials and Processes important?
During its life, a satellite is confronted to many aggressive environments including the ones on ground like corrosion and ageing.
During launch a satellite is exposed to high levels of acoustic noise, vibration and transitory G forces, potentially causing stress corrosion in susceptible alloys or composites. Pyrotechnic shocks are also triggered as secured satellite elements such as antennas are deployed once in orbit.
Once in orbit the single most violent part of a satellite's career is over and done with, but the space environment is far from welcoming. A satellite in low-Earth orbit passes from day into night many times a day. This 'thermal cycling' triggers abrupt temperature changes with can induce thermal stress, vibration and cracking.
Ultraviolet radiation in unfiltered sunlight as well as atomic oxygen particles may crack susceptible plastics and coatings. Optical surfaces and integrated circuits have to resist the onslaught of ionised radiation and charged particles as well as UV, while prolonged vacuum exposure can lead to materials outgassing – the same phenomenon that causes new car interiors to smell – threatening harmful contamination on delicate instrument surfaces as these unwanted substances condense.
But the deep knowledge of materials and manufacturing applied by the Materials and Processes domain offers means of limiting a spacecraft's vulnerability to these malign effects.
Last update: 16 September 2009