Volume 3, Issue 8 (September 2006)
Mechanical Impact Testing: Data Review and Analysis
Since the 1950s, when first the Army and then NASA developed mechanical impact testing of materials, researchers have continued efforts to gain a better understanding of the chemical, mechanical, and thermodynamic nature of the phenomenon. The impact mechanism is a proven ignition mechanism, which must be considered and understood in the design of an oxygen system. The use of test data from this test method has been questioned because of the lack of a clear method of application of the data and variability found between tests, material batches, and facilities. This effort explores a large database, which has accumulated over a number of years, and its overall nature. Moreover, testing was performed to determine the statistical nature of the test procedure to help establish sample size guidelines for material characterization. The current practice of reporting reaction frequency data at dropped energy rather than energy the sample receives does not offer a way to compare data between facilities.