Investigation of the Budd slurry process for the production of short random fiber preforms

The Budd slurry process developed and patented by the Budd Company is a fast, efficient and relatively low cost process for making random chopped fiber preforms. A number of different parts, such as bumper beams and truck cab storage box, have been produced in the automotive industry using this process. This investigation considers the effect of important process and material parameters, such as tank speed, fiber length, fiber weight and binder type, on fiber distribution in preforms and consistency of the Budd slurry process. A Design of Experiments (DOE) approach was used to produce truck cab storage box preforms. The fiber distribution was measured at different locations of these preforms. Furthermore, the tensile strengths of specimens taken from preforms as well as molded parts were determined. Based on these measurements, recommendations are made for producing preforms with low variability in fiber distribution and high strength.