Long term exposure and cycling tests of syntactic foam buoyancy material used in DSRV Alvin

Abstract

These test were conducted to determine the long-term water absorption characteristic of ALVIN's syntactic buoyancy material when subjected to repeated hydrostatic loading equal to ALVIN's design depth of 6000 feet. The 24 samples tested were removed from each section of the current buoyancy packages and represents the best material of 120 samples, as determined by previous short term tests reported in Ref.1. Two samples of material poured by WHOI at Otis AFB during the major overhaul of the winter of 1964-65, and a sample of XP-241-40 (3 MC.) are included in this report.