An empirical model for the automated deposition of thermoset composite

Automated tape deposition is an established technology for manufacture of aircraft components for secondary and primary applications. To deploy prepreg onto tooling a numerically controlled machine unwinds prepreg from a spool and attaches it to a tooling surface using one or more rollers. Future civilian aircraft programs will use increasing amounts of composite parts, which will be made by automated deposition to meet production rate requirements, improve quality and reduce cost over current manual layup. In this paper we will establish an empirical relationship between the controllable variables of an automated deposition system and the quality of the product. The variables that can be controlled are speed, temperature, consolidation pressure and tension on the backing paper. Understanding of the impact of these variables on the final product quality is low and consequently, no process model for the deposition of thermoset material can be found in literature. Using void content and ply thickness after deposition as a quality measure, we will attempt to establish a model for the processing variables and their impact on void content. Our results show that pressure is the most significant variable for thermoset deposition.