Establishment of an Inline Quality Assurance Method for Fiber Sprayed Preforms

Components made from fiber reinforced plastics are increasingly applied due to their high potential for lightweight design. However, the high material and production costs are critical for establishing components in cost sensitive markets like the automotive industry. A solution to reduce material costs is the additive 3D-fiber spraying process. This preforming technology enables cost-efficient and net-shaped manufacturing of long fiber (25 – 50 mm) preforms with minimal waste directly from the roving. Therefore, this preforming technology is interesting for parts with a complex geometry where textile preforming reaches its economical limitations regarding draping and nesting strategies. However, this technology is affected by process fluctuations. For reproducible properties, the 3D-fiber spraying process is integrated in a production unit. Within this unit, an inline quality assurance system based on detection of process fluctuations and a self-regulating compensation system is established. The inline quality metrology is realized by an optical system. Local deviations of fiber distribution and orientation are detected and used for individual compensation using continuous carbon fibers. The fiber pattern is shaped based on an inline simulation of the mechanical component properties. In this paper the suitability of the optical inline assurance system for the fiber spraying process is investigated.