Effect of process parameters and materials on the dimensional accuracy of FDM parts

The application of FDM technique for prototyping purposes in the industries such as aerospace and medicine has brought to attention the importance of dimensional accuracy of the manufactured models. The dimensional accuracy of FDM printed parts depends on various process parameters including layer thickness, raster width, infill pattern, etc. that influence the overall part accuracy. The purpose of this study is to make a comprehensive review of publications that investigated the effect of process parameters on the dimensional accuracy of FDM printed parts in order to understand the individual effect of each process parameter as well as to find out the optimal levels of each parameter according to the types of material. Overall 31 articles that investigated the influence of three process parameters, namely layer thickness, extrusion temperature, and part orientation were reviewed and summarized in terms of the material types that were used such as ABS, PLA, and other resins. The main findings indicating the optimal level of process parameters and the methodology of each article was summarized in the tables. The current results of the research found that the layer thickness values between 0.1 mm and 0.2 mm are preferable for ABS and PLA parts, whereas ASA and Nylon parts tend to be accurate with higher layer thickness values. Low values of extrusion temperature are found to be preferable, this parameter is also less dependent on material type. In terms of part orientation, 0° and 90° are found to be optimal levels for ABS and PLA printed parts, respectively. In addition, the optimal level of each process parameter is likely to vary with secondary factors such as the geometry of the part, resin type, and the different dimensions of the part. Therefore, it was concluded that in understanding the effect of each process parameter on the dimensional accuracy of FDM printed parts, the influence of secondary factors should also be considered and investigated.