An Investigation on Process Capability Analysis for Fused Filament Fabrication

Additive manufacturing (AM) has become a popular manufacturing technology today. Many companies have been investing in AM technologies and skill development to carefully integrate them into their capabilities. Despite its benefits, AM has several disadvantages that require in-depth analysis and process engineering. This research focuses on the reproducibility issue of fused filament fabrication (FFF) for polylactic acid printing to reveal whether the AM technology can produce parts comparable to those by traditional or subtractive manufacturing. For this purpose, identification of optimal process parameters and process capability analysis are integrated to achieve repeatable minimum deviation from target dimensions. First, a design of experiments is planned and performed to determine the optimal combination of significant factors to ensure dimensional accuracy. Then, process capability analysis under optimal factor settings is performed to examine whether the printed part dimensions satisfy the target performance levels. Findings from this study show the FFF process can match the reproducibility of manufacturing parts produced by traditional manufacturing technologies.