Rapid Prototyping (RP) expedites the transition from the design concept to a physical model. With RP, objects are created from thin layers, i.e., by Layered Manufacturing (LM). The most common LM technique, stereolithography, uses a liquid photopolymer selectively solidified by an ultraviolet laser.

Mechanical properties of photopolymers can be improved by the addition of short-glassfibres. In this thesis, a novel process for Rapid Layered Composites Manufacturing (RLCM) is developed. RLCM overcomes several fabrication problems caused by the introduction of fibres into the photopolymer liquid:​ (1) thin layer formation from a viscous mixture;​ (2) fibre settling;​ and (3) lack of inter-layer fibre penetration. The distinguishing features of the proposed process are:​ (1) external fibre-resin mixing supply source;​ (2) precisely controlled liquid deposition from above;​ and (3) selective solidification by a scanning pattern with layerto-layer interconnecting features. To arrive at the above process synthesis, first, the basic properties of the constituent materials were experimentally investigated;​ second, the RLCM process, originally synthesized using the Axiomatic Design Theory, was iteratively improved upon by analysis of the fabricated parts.

The constituent materials were studied to evaluate the fibre-photopolymer interaction. The high strength of the fibre-solid photopolymer interface was verified by single-fibre pullout tests. Fibre-liquid photopolymer interaction was observed through rheological measurements which determined the relationship between the composite liquid's viscosity and (a) the fibre concentration and (b) the fibre aspect ratio.

Axiomatic Design Theory was employed for RLCM-process synthesis. The present design resulted from several cycles of evaluation and modification based upon the Independence and Information Axioms.

RLCM process output was analyzed in terms of parts’ geometric quality and mechanical properties. The geometric quality was assessed by examining individual layers. Fluidmechanical layer-formation models were employed to interpret layer-to-layer thickness variations.

Modelling mechanical properties of the short-fibre composites requires information about the fibre orientation and length. Thus, three-dimensional fibre-orientation distribution was measured with a novel methodology where two closely spaced consecutive cross-sections are examined. The method’s novelty lies in accurately calculating the transformation between the cross-sections and additionally estimating the fibre length.

Mechanical properties of layered composites are of importance since such parts may directly serve as functional prototypes. These properties were modelled employing modified rule of mixtures. The models matched well the tensile test results, which demonstrated a significant improvement (80%) in modulus with reinforcements