Carbon/Carbons and Their Industrial Applications

Electric propulsion reliability: Statistical analysis of on-orbit anomalies and comparative analysis of electric versus chemical propulsion failure rates

Mu Space Engineering Spacecraft-C (MUSES-C) was launched into the transfer orbit in May 9, 2003. Microwave discharge ion engines are used as its primary propulsion system. The Data Relay Test Satellite (DRTS) with 1.8kW/250mN-class hydrazine DC arcjet thruster systems was launched on September 10, 2002, and now on service on the geostationary orbit. Ion engine systems onboard Engineering Test Satellite VIII (ETS-VIII) will be also launched in 2004 by the H-IIA rocket. Basic re searches of many kinds of electric thrusters are also being carried out in lots of academic places.

/pdf/an-overview-of-electric-propulsion-activities-in-japan-5aicz2t8zu.pdf

An overview of electric propulsion activities in japan

http://www.esa.int/gsp/ACT/doc/MAD/pub/ACT-RPR-MAD-2013-LowThrustToCircumsolarSpace.pdf

Time-optimal trajectories to circumsolar space using solar electric propulsion

The primary life-limiting mechanism for state-of-the-art ion thrusters is erosion of the accelerator grid by charge-exchange ions produced in the plume of the thruster. This paper reviews carbon-based grid development activities, specifically addressing grid manufacturing, optics performance, and launch and operational survivability.

Review of carbon-based grid development activities for ion thrusters

Accomplishment and prospect of isas electric propulsion

New carbon-carbon composite (C/C) materials for a 20 cm ion engine grid system have been evaluated. Basic physical properties of two materials, named CC2000 and CC3000, have been evaluated. The measurement items and results are 1.9 g/cc of bulk density, 120 ~ 130 MPa of flexural strength, 35 ~ 45 MPa of flexural elastic modulus, 91 MPa of tensile strength, 80 GPa of tensile elastic modulus or Young’s modulus, no detrimental remaining strain by ten cycle tension-compression test, 0.3 of Poisson’s ratio, the order of -1x 10 -6 /K of thermal expansion coefficient, the order of 1x10 -5 m 2 /s thermal diffusivity at room temperature, 0.5 ~ 0.6 of thermal emissivity, �� x10 -3 Ωm of electrical resistivity for CC2000, and 5 x10 -3 Ωm for CC3000 at room temperature. A drill machining has been attempted to the new materials. It can be said by visual inspection that the result is excellent for both materials. Consequently, using CC2000 material, actual 20 cm diameter grid system has been designed and fabricated.

Y. Shimizu

Papers

Accomplishment and prospect of isas electric propulsion

Evaluation of new carbon-carbon composite material for a 20 cm ion engine