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This study aims to compare the accuracy offered by 3D Slicer Software in printing end-use parts inside a Fused Deposition Modeling process of Additive Manufacturing. The purpose, in particular, is to investigate the surface quality and the dimensional stability of the manufactured parts comparing the effect of selecting a different 3D Slicer tool among Simplify3D, Cura and Slic3r 3D. With this scope, parts were produced using these process tools while results were analysed in terms of accuracy, production time and consumption of material. Results, graphically and visually presented, show significant differences in the dimensional and surface accuracy with an optimum outcome offered by the Simplify3D as best 3D slicer tool. The Simplify3D slicer has essential advantages in printed end-use parts because creates the 3D models with significantly better accuracy and quality support.

A growing concern over environmental issues and the common interest to find a viable alternative to the use of glass or carbon composite reinforcements has led to an increased attention in ecologically sustainable polymer composites. These „green” materials are made by natural fibers, as reinforcement, filled with natural-organic fillers, i.e. derived from renewable or biodegradable sources. At the same time, this relatively new class of materials faces several limits in comparison to traditional composites especially regarding the properties of resistance. This paper investigates the advantages of use of combination of natural fibers for improving mechanical proprieties of „green” composite materials. At the moment, the prevailing opinion is that green composites are not usable in structural applications, and, as a consequence, have to be relegated to unworthy applications (as fillers). On the contrary, there are several evidences that mixing different natural fibers (in practice usually called „hybridization”) leads to an improvement of these material properties. Although usually quite limited in terms of percentage, these improvements from time to time allow a new enlargement in the fields of applications for green composites. Following a large state-of-the-art on green composites, including potential benefits and limits of these materials, the paper proposes several examples of hybridization showing its effect on mechanical proprieties.

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This paper investigates the opportunity of implementing FE simulations and rapid prototyping tecniques on titanium implant in maxillofacial surgery case based on osteotomy. Maxilla region was recorded by Cone Beam CT with high resolution and optimal radiation. Then, it followed the medical image reconstruction into 3D voxelized model. This model was converted both, to stl surface model for rapid prototyping, CAD modeling and FE mesh for simulation purposes with keeping good volume and dimensional consistency. Stl meshed surface was imported into CAD software, as initial 3d structure, which is used for parametric and customized design of implant. Since, the osteotomy is final application, it wassimulated the cutting and shifting of maxilla for proper correction by digital prototyping. Then, the fixation points for shifted maxilla were determined by surgeon to provide steady and tight joints between implanting screws and maxilla. Applied implant was given in initial standard flat configuration. Flat implant configuration was adapted by complex 3D bending in CAD software to be customized towards surface conformity of maxillofacial anatomy. By FE simulation in MSC Patran/Nastran, it was performed the stress analysis of implant with different thickness configurations and 3D bending, which provides the optimized implant model with best fit dimensions. Optimized implant model and corresponding body model were converted into physical models. RP model of maxilla was post-processed by cutting and boring to provide an adequate implant positioning according to digital prototypes. This approach facilitated the preparation of complex shaped implants in swept and lofted form, what had to be in high degree of conformity to anatomy surface. To approve a good practical opportunity, it was applied and tested in concrete surgery case of maxillofacial osteotomy.

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Additive manufacturing technologies enable rapid prototyping of different parts, according to the three-dimensional model software solution. This paper presents some aspects of fused deposition modeling technology and its application in the wood industry. The fused deposition modeling technology was initially developed for three-dimensional printing of plastic parts, whereas acrylonitrile butadiene styrene and polylactic acid plastics filament are commonly applied. Possibilities for application of different composites with fused deposition modeling in the wood industry are reviewed and presented in this paper. Several industrial applications were considered also, from aspects of material durability, mechanical strength, low cost, and customization. Directions of further research have been discussed, considering graphene and carbon nanotubes as composite reinforcement materials and bio-organic composites with wooden particles or fibers mixed into the polymer matrix. Development of new composites for use with the fused deposition modeling technology is promising area taking into account that new low-cost extruders are already commercially available, as a support to fused deposition modeling device. Three-dimensional printing is very convenient for investigation of different custom-made composite materials, as well as custom shapes of final parts, starting from powders, their mixing, drawing of composite material filament, which are further used for three-dimensional printing with solidification and fabrication of custom-made products. New composites for fused deposition modeling, made of wood and plastic combinations were experimentally investigated for use as functional and customized elements of furniture. Obtained results strongly indicated that both new composite materials and fused deposition modeling printing can be efficiently used for broad customization from aspects of material properties and product shapes, thus enabling low-cost fabrication of small series of complex furniture elements, especially fixtures or clamp tools.