MICROSTRUCTURE OF ALUMINIUM ALLOY FRAGMENTS PRODUCED BY EXPLOSIVES

摘要

Experiments were carried out with 49 g charges of PE4 placed on or near 12.7 mm thick aluminium alloy plate and 1.2 mm thick aluminium alloy sheet. It was found that brisance effects, such as the creation of a zone of shattered material, were seen when the explosive was in contact with the alloy, but that the effects were reduced as absorbent material, simulating clothing, was placed between the charge and the alloy. Microhardness measurements made with the high strength 7075-T6 alloy, showed no significant increase in hardness as a result of the explosive event However, the lower strength 2014-T3 alloy showed an increase of hardness from 112 HV to 140-146 HV Although significant this was less than the increases seen in steels of the same initial hardness. Fragments taken from plates in contact with or very close to the explosive showed signs of internal spalling. These results could be of significance in the investigation of aircraft explosive events.