Innovative Tungsten Alloys for Advanced Propulsion Systems

Non-conventional technologies are needed to revolutionize space propulsion. Development of materials with improved properties is essential to increase performance and reduce cost. Advancements are needed for components in solid and hybrid rocket, high powered electrical, beamed energy, and nuclear propulsion systems. Innovative processes for fabricating net shape, tungsten-rhenium-hafnium carbide alloy components are proposed. Tungsten is being used for its high melting temperature (6170?F) and chemical stability. However, conventional tungsten materials have to be forged to get adequate properties. Forging tungsten into complex shapes is difficult and has limited its application. Small additions of rhenium improve the ductility of tungsten without significantly decreasing the melting point. Also, dispersion hardening by additions of HfC increases the high temperature strength and creep resistance by pinning grain boundaries. In Phase I, W-Re-HfC materials and processing parameters were developed, and W-Re-HfC samples were fabricated for characterization and hoop tensile testing. In hoop tensile tests, Phase I W-Re-HfC was stronger than baseline W-Re or W. Solid rocket nozzle inserts were fabricated and are being hot fire tested at ATK-Thiokol to demonstrate non-eroding nozzles. Development of these materials will allow the production of components with unique properties and reduce the size, weight, and cost of propulsion systems.