Analysis of microstructure of laminated polymer composite material of metal composite overwrapped pressure vessel

The microstructure of a layered polymeric composite material used in the construction of a metal composite over- wrapped pressure vessel is investigated. The purpose of this work was to evaluate the parameters characterizing the structure of a laminate polymer composite material. Due to their technological and structural features, laminated polymer composite materials have a number of operational disadvantages that lead to a reduction in the overall level of strength characteristics. From the different zones of the nine-layer composite shell of the metal composite overwrapped pressure vessel, four vertical flat samples of the composite material for the manufacture of thin sections were cut out. The method of electron-scanning microscopy was used. The analysis of the percentage confinement of fibers in the ma- trix was carried out. The structure of the layered polymeric composite material is uniform with the presence of a dis- persion of distances between the fibers. The analysis of porosity in a composite material was carried out. The analysis of the structure of composite materials with different porosity has shown that with increasing pore area and their num- ber, the strength characteristics of composite tapes and reinforcing fibers decrease. Using the “mixture rule” and “polydispersity model”, the values of the effective modulus of elasticity of the composite material are estimated. It is determined that the modulus of elasticity of the composite material in the zone of the flange of the composite shell is less than at the equator. A complex evaluation of the quality of a laminate polymer composite material used in the structure of a metal composite overwrapped pressure vessel was carried out. The obtained results of inhomogeneity of the me- chanical properties of the composite shell are necessary for design calculation of the stress-stain state of metal over- wrapped pressure vessels.