Accession Number : ADA307044

Title :   Projectile-Impact-Induced Fracture of Liquid-Filled, Filament-Reinforced Plastic or Aluminum Tanks.

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CEN TER

Personal Author(s) : Stepka, Francis S.

PDF Url : ADA307044

Report Date : JUN 1966

Pagination or Media Count : 20

Abstract : An experimental evaluation was made of the impact-fracture characteristics of liquid-filled tanks with walls of several filament-reinforced plastic materials. Comparisons were also made with tank walls made of an aluminum alloy. The materials evaluated were glass-filament- reinforced urethane or epoxy, Dacron-filament-reinforced urethane, steel-wire-reinforced urethane, and 2014-T6 aluminum alloy. The liquid contained in each tank was either water or liquid nitrogen. The impacting projectiles were 7/32-inch-diameter spheres of steel or aluminum, which were accelerated to velocities of 5500 and 6500 feet per second, respectively. The glass-reinforced plastics were most resistant to impact-fracture damage; the Dacron-reinforced urethane was least resistant. The glass-reinforced plastic walls were also more resistant to fracture than the aluminum alloy walls. Impacts into liquid-nitrogen-filled cylindrical tanks with approximately 1/32-inch-thick walls of these materials resulted in bursting of an aluminum wall stressed prior to impact to only 10 percent of the material ultimate strength, compared with only a puncture and local delamination of the outer filament layer of glass-reinforced epoxy walls stressed prior to impact to as high as 40 percent of the material ultimate strength.

Descriptors :   *IMPACT STRENGTH, *REINFORCED PLASTICS, STRESS ANALYSIS, ALUMINUM ALLOYS, PROJECTILES, HIGH VELOCITY, IMPACT TESTS, DAMAGE ASSESSMENT, HIGH PRESSURE, HIGH STRENGTH ALLOYS, STRENGTH(MECHANICS), FRACTURE(MECHANICS), GLASS FIBERS, EPOXY LAMINATES, WALLS, FILAMENTS, LIQUID NITROGEN, EPOXY RESINS, DELAMINATION, PROPELLANT TANKS, IMPACT ACCELERATION, URETHANES, WATER TANKS, BURSTING STRENGTH.

Subject Categories : Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE