From Abstract: "Fuel tubes of enriched uranium-aluminum alloy were melted to various degrees of severity in the SPERT I reactor as a part of a program to evaluate reactor operating hazards. The heat flux encountered during the tests ranged from 200,000 to 650,000 pcu/(hr)(ft^2). The time required for the metal temperature to reach the melting point from the time when burnout began varied from 1.3 to 4.9 seconds. During these tests, pressure pulses were produced at a frequency of about one per second with peaks of about 150 psi."