Engineer, Non-Metallic Materials Division, U. S. Naval Ordnance Laboratory, White Oak, Silver Spring, Md.
Pages: 3 Published: Jan 1963
Filament-wound pressure vessels are being studied at the Naval Ordnance Laboratory by the Zandman photostress technique. With this technique, a thinlayer of special plastic is adhered to the surface to be studied, the interface having been made reflective. As the surface strains of the vessel are transmitted to the plastic, the plastic exhibits a birefringence which is proportional to the difference in principal strains. With the use of a polariscope, the direction and magnitude of the principal strains may be measured over the coated area. Many elements of the filament winding process which affect stress distribution in the vessel may be studied using this technique.
Paper ID: STP44438S