Polymer-Ceramic Composite for Manufacturing Dielectric Parts of Low-Thrust Space Engines

Abstract

Heat-resistant dielectric composite materials based on organosilicon polymers for the manufacture of parts for low-thrust space engines, for example, the discharge chamber of a high-frequency ion engine, which is one of the types of electric rocket engines, have been synthesized and their properties have been studied. A composition of a polymer-ceramic material based on dimethylsiloxane rubber reinforced with α-phase silicon dioxide powder has been proposed. The composite meets a wide range of requirements for the material of discharge chambers, among which vibration resistance, radio transparency, and heat resistance up to 400°C should be highlighted. A relationship has been established between the heating rate during postvulcanization of a polymer-ceramic composite and its mass loss. It has been shown that the temperature regime during re-vulcanization/annealing of the composite in vacuum significantly affects the operational properties of the discharge chambers. The results of the study have allowed us to successfully produce samples of discharge chambers from this composite for a laboratory model of a high-frequency ion engine with a beam diameter of 100 mm.