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The Low Earth Orbit (LEO) environment exposes spacecraft structures to ultraviolet (UV) radiation, atomic oxygen (AO), vacuum and temperature variation. Carbon Fiber/Polyether Ether Ketone (CF/PEEK) composite can be an ideal material to counter such factors. However, there is limited data on the performance of CF/PEEK composite in a LEO environment...
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Context 1
... a detailed computer-aided design (CAD) model of the external PCB. The external PCB measured 78 mm long and 80mm wide. Three CF/PEEK samples were bolted to the external PCB. Each sample consisted of two pieces of CF/PEEK thermally welded together. The overall dimension of each sample was 50 mm long, 10 mm wide and 2 mm thick, as illustrated in Fig. 7. The CF used was polyacrylonitrile (PAN) based plain woven carbon fabric manufactured by Toray. The PEEK resin was manufactured by Victrex. In a previous satellite developed by Okuyama laboratory termed Shinen-2, plain woven CF/PEEK was used as the main external structure ...
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... strain measurements with respect to temperature showed a similar change pattern with the test in the strain gauge attachment method illustrated in Fig. 9. The strain decreased with increasing temperature, as illustrated in Fig. 17. The CTE for sample with no coating and UV coating varied between 0 and 8 ppm/°C, as illustrated in Fig. 18. There is an average difference of approximately 0.8 ppm/°C between sample with no coating and UV coating. Potential reason for the difference External PCB was due to minor strain gauge misalignment with the fiber direction in ...
Citations
... However, only a few polymers have been used in fiber-reinforced form. For example, in thermoset carbon epoxy and bismaleimide [14][15][16][17][18] and in thermoplastic matrices, only PEEK has been used [7,[19][20][21][22][23][24]. The other thermoplastic polymers have not been used yet. ...
... However, this can be minimized by an optimized selection of fiber and polymer matrix. For example, choosing carbon fiber and PEEK polymer creates the overall CTE of the composite in the range of 0 to 8 × 10 −6 /°C [20]. The overall CTE of graphite epoxy can also be altered from −0.06 to −2 × 10 −6 /°C by changing the fiber layup [24]. ...
... However, this can be minimized by an optimized selection of fiber and polymer matrix. For example, choosing carbon fiber and PEEK polymer creates the overall CTE of the composite in the range of 0 to 8 × 10 −6 / • C [20]. The overall CTE of graphite epoxy can also be altered from −0.06 to −2 × 10 −6 / • C by changing the fiber layup [24]. ...
This review paper discusses the effect of polymers, especially thermoplastics, in environments with low earth orbits. Space weather in terms of low earth orbits has been characterized into seven main elements, namely microgravity, residual atmosphere, high vacuum, atomic oxygen, ultraviolet and ionization radiation, solar radiation, and space debris. Each element is discussed extensively. Its effect on polymers and composite materials has also been studied. Quantification of these effects can be evaluated by understanding the mechanisms of material degradation caused by each environmental factor along with its synergetic effect. Hence, the design elements to mitigate the material degradation can be identified. Finally, a cause-and-effect diagram (Ishikawa diagram) is designed to characterize the important design elements required to investigate while choosing a material for a satellite’s structure. This will help the designers to develop experimental methodologies to test the composite material for its suitability against the space environment. Some available testing facilities will be discussed. Some potential polymers will also be suggested for further evaluation.
The effects of electron beam irradiation were examined on perforation holes and fragments from quasi-isotropic carbon fiber reinforced plastic plates (CFRP plates). CFRP plates with a total dose up to 60 MGy of electron beam irradiation were prepared for hypervelocity impact experiments. The perforation holes of CFRP plates in the hypervelocity impact experiments were decreased with electron beam irradiation when aluminum alloy spherical projectiles (2017-T4) of diameter of 1 mm struck at an impact velocity of 5 km/s. However, a slight reduction in the size of the perforation hole was observed at 2 km/s. Fragments ejected from CFRP plates were examined after collection from the impact side and rear side of the targets. The cumulative number distributions of fragment length and aspect ratio were compared among specimens with different total doses.
