Low Cost, Net Shape Fabrication of Propulsion and Hot Gas Components

"To meet DoD and IHPRPT requirements, the cost of rocket enginesneeds to be reduced while increasing performance. Rhenium isbeing used for nozzles and hot gas valve components because ofits high melting temperature and chemicalstability. However, the difficulty of forming rhenium and otherrefractory metals into complexshapes has limited their application in the past. PlasmaProcesses, Inc.has demonstrated rapid, low cost fabrication of refractory metalcomponents using Vacuum Plasma Spray processes. The techniqueinvolvesdepositing material onto a mandrel of the desired shape andsubsequentlyremoving the mandrel. A primary advantage over othertechniques is that net-shape forming of components significantlysimplifiesand reduces the cost of fabrication due to the high materialutilization andreduction of machining. Analysis shows that a non-erodingnozzle will improve AMRAAM's ISP by 6 seconds. In Phase I, arhenium nozzle was fabricated, composite wrapped, andsuccessfully hot fire tested in less than onemonth. The hot fire testing demonstrated the ability of net shapecomponents to meet stringent thermal and mechanical requirementswith zero erosion.Exploitation of these rapid processing techniques decreases thecost andmanufacturing time of rocket engine nozzle and hot gascomponents while boosting performance.BENEFITS: The results of the Phase I effort clearly demonstrate the ability to mateinnovative rapid manufacturing technologies with ref