Examination of Processing Variables in the pultrusion of Glass Reinforcements with an Epoxy-Anhydride Resin System.

摘要

Three stages of the pultrusion process were investigated for potential value in process control. Collectively, they represent the three major steps necessary for the manufacture of composite materials by pultrusion: fiber dispensation, resin application, and resin cure. The purpose was to determine whether the processing conditions imposed by each of these steps have a direct correlation to the physical properties exhibited by the final product. In order to examine the first two stages, a series of experiments were conducted involving the process components which precede the raw materials entry into the heated die. Specifically, these were the fiber tension as adjusted in the creels and the viscosity of the resin in the bath as a function of time. The third stage of the process was studied through a series of experiments designed to gauge the effect of varying the processing parameters associated with the heated pultrusion die which are the line speed and die temperature. The experimental results were evaluated by examining variation in mechanical properties of pultruded stock as produced under the various sets of conditions. Short beam shear and flexural tests were performed and measurements of product density, degree of cure, and void content were made. The results provide a solid empirical knowledge base for the process and a relative ranking of importance of the three stages in a control strategy.