Additively Manufactured Scramjet Assemblies

The development and deployment of air-breathing hypersonic weapons and other scramjets will be a pillar of DoD offensive strategy over the next ten years. Advances in manufacturability are one of the key technologies that will expedite their availability in the Air Force inventory. Current fabrication methods have long lead times, high part rejection rate, and great expense due to the number of parts requiring hand-rework by skilled fabricators. Physical Sciences Inc. (PSI) will solve these problems by continuing to develop our additive manufacturing (AM) plus brazing process that allows scramjet duct segments, and other components, to be joined together into large-scale, highly complex scramjet assemblies. In the Phase I, PSI and our STTR partner fabricated subscale test pieces to evaluate suitable geometries, AM process parameters, and post processing steps required to manufacture and join AM parts with internal passages less than 1.25 mm (0.05”) and parts made of different metals. We successfully brazed multi-metal test components and demonstrated capability to contain 21 MPa (3000 psi) of internal pressure. In Phase II, we will extend this joining architecture to produce joined, AM scramjet duct segments suitable for testing in a direct connect wind tunnel test facility.