EVALUATION OF NEW CARBON-CARBON COMPOSITE MATERIAL FOR A 20 CM ION ENGINE

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.