Liquid Rocket Engine Combustion Components Fabricated from ZrB2/BN Composite Using Electroconsolidation (TM) Rapid Densification Technique

The goal of this program is to design and fabricate selected liquid rocket engine combustion components. This goal will be accomplished by developing a low-cost, near net-shape technology for fabrication and rapid densification of ablation and oxidation-resistant LRE components for a wide variety of Air Force missions. The material which will be used for this purpose is zirconium diboride/boron nitride composite, which has good ablation resistance, thermal shock resistance, and good erosion resistance dur to high hardness, but much greater toughness than the monolithic form of ZrB2. The ZrB2/BN composite will have an interpenetrating microstructure of elongated polycrystalline cells of the base material, zirconium diboride, separated by cell boundaries-very thin layers of low shear strength refractory material, boron nitride. This interpenetrating microstructure imparts toughness and thermal shock resistance to the material. The advantage of this technology is that complex microstructures are created completely from inexpensive powders, by mixing them with polymer binders and spinning this mixture into fibers. These fibers are wound into a complex-shape part, which is then rapidly densified via Electroconsolidation to near net-shape with minimal post machining required, resulting in a low-cost process.