3D roughness profile model in fused deposition modelling

Purpose - The paper aims to predict the surface roughness of fused deposition modelling prototypes. Since average roughness is not comprehensive, this study aims to extend the characterization to all the roughness parameters obtainable by a profilometric analysis. Design/methodology/approach - A theoretical model of the 3D profile is supplied as a function of process parameters and part shape. A suitable geometry was designed and prototyped for validation. Data were measured by a profilometer and complemented by microscopic analysis. A methodology based on the proposed model was applied to optimise prototype fabrication in two practical cases. Findings - The proposed profile is effective in describing the micro-geometrical surface of fused deposition modelling prototypes. The third dimension enables the calculation of amplitude, spatial and hybrid roughness parameters. Research limitations/implications - Because of mathematical assumptions and technological aspects, the validity of the model presents limitations related to the deposition angle. Practical implications - The method is an effective tool in the process planning stage: it enables knowing in advance how to assure part specifications delivering a set of technical choices. Two practical applications point out the usability in the product development and process parameters optimisation. Originality/value - This work fulfils an identified need to predict a complete surface characterization of fused deposition modelling technology.