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Fused deposition modelling (FDM)-printed parts can be treated with various post-processes to improve their mechanical properties, dimensional accuracy and surface finish. Samples of polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) parts are treated with annealing to study a ceramic powder mould’s effectiveness in order to avoid dimensional part deformation. The variables chosen are annealing temperatures and the usage of a ceramic powder mould to avoid part deformations. A flexural strength test was carried out to evaluate the mould’s influence on the mechanical properties of the part. The effectiveness of the mould has been evaluated mainly attending to the length of the part, because this is the dimension most affected by deformation. A polynomial approximation to a deformation’s length and the effectiveness of the mould allows for their prediction. Results obtained show that effectiveness increases with the annealing temperature. Nevertheless, mould effectiveness decreases when parts are fabricated with PLA, because it is a semi-crystalline thermoplastic, and it suffers a lower shrinkage during thermal post-process than amorphous polymers such as ABS. Attending to the flexural strength test, mould has no significant influence on the mechanical properties of the treated parts in both materials studied.

Delamination is one of the main problems that occur when machining fiber-reinforced composite materials. In this work, Types I and II of delamination are studied separately in edge trimming of basalt fiber reinforced plastic (BFRP). For this purpose, one-dimensional and area delamination parameters are defined. One-dimensional parameters (Wa and Wb) allow to know average fibers length while the analysis of area delamination parameters (Sd) allow to evaluate delamination density. To study delamination, different tests are carried out modifying cutting parameters (cutting speed, feed per tooth and depth of cut) and material characteristics (fiber volume fraction and fiber orientation). Laminates with a lower fiber volume fraction do not present delamination. Attending to one-dimensional parameters it can be concluded that Type II delamination is more important than Type I and that a high depth of cut generates higher values of delamination parameters. An analysis of variance (ANOVA) is performed to study area parameters. Although delamination has a random nature, for each depth of cut, more influence variables in area delamination are firstly, feed per tooth and secondly, cutting speed.

The post-process thermal treatment of thermoplastics improves their mechanical properties, but causes deformations in parts, making them unusable. This work proposes a powder mould to prevent dimensional part deformation and studies the influence of line building direction in part deformations in a post-process thermal treatment of 3D printed polymers. Two sets of ABS (acrylonitrile butadiene styrene) test samples manufactured by fused deposition modelling (FDM) in six different raster directions have been treated and evaluated. One set has been packed with a ceramic powder mould during thermal treatment to evaluate deformations and mould effectiveness. Thermogravimetric tests have been carried out on ABS samples, concluding that the thermal treatment of the samples does not cause degradations in the polymeric material. An analysis of variance (ANOVA) was performed to study internal building geometry and mould influence on part deformation after the thermal treatment. It can be concluded that powder mould considerably reduces dimensional deformations during the thermal treatment process, with length being the most affected dimension for deformation. Attending to the length, mould effectiveness is greater than 80% in comparison to non-usage of moulding, reaching 90% when the building lines are in the same direction as the main part.

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