Residual stresses reduction in filament wound composite tubes

Sources of residual stresses in composite materials and methods of their re ductions are discussed and analyzed rigorously for one dimensional micro-me chanical model and numerically for axisymmetric filament wound composite tu be model using finite element analysis (FEA). The incorporation of mechanic al preload to the Fabrication process is discussed and two designs of an ex pandable mandrel are proposed. Two processes, conventional and with preload , are numerically simulated for residual stresses.