The Influence of Cure Pressure on Microstructure, Temperature Field and Mechanical Properties of Advanced Polymer-matrix Composite Laminates

Under a given curing process, various cure pressure conditions were designed to evaluate the influence of cure pressure on composite microstructure, temperature field and mechanical properties. A series of composite laminates of different technological parameters were manufactured. The locations of defect in the composite laminates were determined using phased array ultrasonic flaw detection technology. A characterization of microstructure within the composite laminates was obtained using optical digital microscope. The tensile properties test was used to establish the relationship between cure pressure and mechanical properties. Results reveal that the delamination exists in the low pressure curing stage (below 0.2 MPa), the voids mainly exist in the two forms of columnar shape and globular shape, and their number and size decrease as the cure pressure increases, the cure reaction moment occurs to delay due to the actual heating rate reduces. The tensile strength increases as the porosity deceases and the tensile modulus is insensitive to the porosity, which are consistent with previous studies.