Cryogenic and elevated temperature hypervelocity impact facility

The hypervelocity impact facility at Space Research Institute (SRI), Auburn University has recently completed a facility upgrade that permits the impact testing of space materials within the cryogenic and elevated temperature range. Sample temperatures within the range of 40–450 K have been achieved for polymer films. These wide temperature range capabilities add to the facilities current testing experience with impact initiated plasma discharge testing for solar cell arrays. The facility utilizes a plasma drag gun to accelerate a variety simulated micrometeorite materials in the 50–150 μm range to velocities between 5 and 12 km/s. For each test 5–50 particles impact the surface of the target sample within an impact area of approximately 15 cm in diameter. The test chamber can accommodate samples up to a meter wide for ambient and heated tests, and 48 cm for cryogenic samples. The gun and test chambers are evacuated by He cryopumps and dry roughing pumps to produce a clean, oil free environment. Utilizing a streak camera and PMT detection system, the correspondence between individual particle size, speed and impact site can be determined. Standard post-analysis yields: micrographs of each impact site, dimensions of the pertinent impact characteristics, individual particle velocity and size estimates.