The NASL Notched Flat Compression Test for Filament Wound Materials. Reinforced Plastics for Deep Submergence and Other High Strength Applications

摘要

The NASAL notched flat method for determining compressive strength of filament wound materials is described. Data are presented for a series of tests, in which a number of different methods of grip construction were employed, indicating good reproducibility, with an overall coefficient of variation of 4.9%. For a material of 2:1 orthogonal construction, with S glass reinforcement, an average compressive strength value of 157,800 psi was obtained in the stronger ('2') direction. This value is within 5% of the average value reported for tests on cylindrical specimens, of similar construction, tested hydrostatically. Very recent data for a material of superior quality, tested by the NASL notched flat method, gave an average value of compressive strength in the '2' direction of 178,000 psi, with an individual high of 192,800 psi. Based on these data, it is believed that laminates of this type may be produced with present day materials which will have compressive strengths of 200,000 psi or higher. (Author)