Cyclic Loading of PBX 9501 and PBX 9502: Compression and Tension

The uniaxial mechanical properties of plastic-bonded explosives (PBX) 9501 and 9502 have been studied extensively over the past 25+ years. Uniaxial, cyclic loading compression and tension tests were performed on PBX 9501 and 9502, spanning a range of temperatures and loading rates. All cyclic tests are analyzed to quantify damage accrual within a specimen as a function of increasing strain for each cycle. One full cycle is defined as the loading, unloading, and relaxation time at zero load. The damage accumulation for each test condition is evaluated using two parameters. The first is the irreversible strain, or residual strain, measured after each full cycle, i.e. at the end of the relaxation time before loading of the next cycle begins. The second is the change in modulus, or stiffness, of each loading portion for each cycle. In the work presented, damage accrual of PBX 9501 and 9502 are determined empirically for both compression and tension cyclic loading experiments.