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This paper aims to investigate the effect of post-processing techniques on dimensional accuracy of laser sintering (LS) of Nylon and Alumide^® and fused deposition modelling (FDM) of acrylonitrile butadiene styrene (ABS) materials.

Additive manufacturing (AM) of test pieces using LS of Nylon and Alumide^® powders, as well as the FDM of ABS materials, were first conducted. Next, post-processing of the test pieces involved tumbling, shot peening, hand finishing, spray painting, CNC machining and chemical treatment. Touch probe scanning of the test pieces was undertaken to assess the dimensional deviation, followed by statistical analysis using Chi-square and Z-tests.

The deviation ranges of the original built parts with those being subjected to tumbling, shot peening, hand finishing, spray painting, CNC machining or chemical treatment were found to be different. Despite the rounding of sharp corners and the removal of small protrusions, the dimensional accuracy of relatively wide surfaces of Nylon or Alumide^® test pieces were not significantly affected by the tumbling or shot peening processes. The immersion of ABS test pieces into an acetone bath produced excellent dimensional accuracy.

Only Nylon PA2200 and Alumide^® processed through LS and ABS P400 processed through FDM were investigated. Future work could also examine other materials and using parts produced with other AM processes.

The service bureaus that produce prototypes and end-use functional parts through AM will be able to apply the findings of this investigation.

This research has outlined the differences of post-processing techniques such as tumbling, shot peening, hand finishing, spray painting, CNC machining and chemical treatment. The paper discusses the advantages and disadvantages of each of those methods and suggests that the immersion of ABS test pieces into an acetone bath produced excellent dimensional accuracy.

The current analysis was conducted to investigate the quality of surfaces and geometry of tracks printed using PolyMideTM CoPA, PolymaxTM PC and PolyMideTM PA6-CF materials through fused deposition modelling (FDM). This study also examined the degree of fusion of adjacent filaments (tracks) to approximate the optimal process parameters of the three materials.

Images of fused adjacent filaments were acquired using scanning electron microscopy (SEM), after which, they were analysed using Image J Software and Minitab Software to determine the optimal process parameters.

The optimal process parameters for PolyMideTM CoPA are 0.25 mm, 40 mm/s, −0.10 mm, 255°C and 0.50 mm for layer thickness, printing speed, hatch spacing, extrusion temperature and extrusion width, respectively. It was also concluded that the optimal process parameters for PolymaxTM PC are 0.30 mm, 40 mm/s, 0.00 mm, 260°C and 0.6 mm for layer thickness, printing speed, hatch spacing, extrusion temperature and extrusion width, respectively.

It was difficult to separate tracks printed using PolyMideTM PA6-CF from the support structure, making it impossible to examine and determine their degree of fusion using SEM.

The study provides more knowledge on FDM, which is one of the leading additive manufacturing technology for polymers. The information provided in this study helps in continued uptake of the technique, which can help create job opportunities, especially among the youth and young engineers.

This study proposes a new and a more accurate method for optimising process parameters of FDM at meso-scale level.