Erosion from hypervelocity impacts with simultaneously launched particles

Abstract

Hypervelocity impacts involving microparticles, typically ranging from micrometers to millimeters in size, are a significant threat in aerospace applications. Degradation of optical components and sensors from collisions with airborne dust and sand can cause light to be scattered and a reduction in resolution. Here we develop a method to launch and characterize impacts from particles ranging from 70–820 µm at speeds > 4 km/s. The methods developed here build on the buckshot method from previous studies while using features unique to the Hypervelocity Facility for Impact Research Experiments (HyFIRE) at Johns Hopkins University. This methodology is then used to impact select target materials with aluminum powders or lunar regolith simulant (JSC-1) at various angles of obliquity to simulate sand and or ash erosion for high altitude vehicles and spacecraft. The velocity distribution of the particle impacts was characterized using ultra high-speed imaging of the impact surface and the degree of surface erosion was measured using post-mortem profilometry. While some of these techniques and specifications are unique to the HyFIRE facility, the methods presented here can be adapted at other hypervelocity testing facilities to study microparticle material erosion.