Particle-Impact Ignition Testing of Three Commercially Available Ignition Resistant Metal Alloys

View Video Presentation: https://doi.org/10.2514/6.2023-1490.vid Oxidizer-rich staged combustion rocket engines face an elevated risk of ignition to interior components due to the impact of particles carried in the propellant flows. The Particle-Impact Shock Tube (PST) at The Aerospace Corporation is being utilized to characterize the particle-impact ignition resistance of various materials for service in oxygen environments. The PST can provide a high-pressure (3.5-31 MPa, 500-4,500 psi), high-temperature (294-772 K, 70-930°F), pure oxygen environment for imaging high velocity particle impacts (up to 355 m/s, 1,165 ft/s). In this study, three commercially available ignition-resistant metal alloys were tested in the PST: Hastelloy® C276, Haynes® 214, and ToughMet® 3. These tests utilized irregularly shaped 600-µm and 1000-µm aluminum particles, with particle impact velocities ranging from 204 to 278 m/s (668 to 911 ft/s). For all samples tested, the larger particles resulted in a higher incidence of particle ignition events, as well as the ignition of a Haynes 214 target. These types of tests can be important for the evaluation of relative ignition risk for specific materials used in the development of liquid-propellant rocket engines.