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World society relies quite strongly on the use of fossil-based conventional plastics. Low cost and versatility paved the way for a wide range of applications. The most used plastics in daily life have been polyethylene (PE), polypropylene (PP), polystyrene (PS), poly (ethylene terephthalate) (PET), and poly (vinyl chloride) (PVC), which, despite advances in processing and manufacturing, generate two major problems: the first one concerns the use of non-renewable resources to obtain the raw materials, and the second one is related with the large amount of waste generated since the disposal methods are still somewhat limited. As the greatest environmental impacts of fossil-based plastics are focused on the phases of obtaining the raw materials and disposal, the use of renewable, biodegradable bio-based plastics brings, as a gain for the environment and the whole society, the reduction of the volume of the plastic waste present, coupled with a reduction in resource consumption. Despite the great contribution that bio-based plastics can make to the environment since they are obtained from renewable biological sources and can be biodegradable, there are certain limitations, like unavailability of biomass, difficulties in cultivation, and high economic costs, which still need to be overcome. A common raw material is starch, which is hydrolyzed to sugar and fermented, e.g., to lactic acid, to make polylactic acid (PLA). Other common biopolymers are thermoplastic starch (TPS) and polyhydroxybutyrate (PHB). Microalgae and seaweed, as a source of biopolymers, can represent an alternative due to their high yields and ability to grow in a wide range of environments. Also, microalgae and seaweed are economical and developments in this field of research have shown to be increasingly promising. Although algae-based plastics are at a very early stage of development, once they will have been commercialized, they are likely to find applications in a wide industrial range, such as food packaging and medicine storage. Another emerging raw material for bioplastics, fossil-based, is methane, for which different sources exist. Methane from natural gas is already used to produce ethylene and propylene in thermocatalytic processes, and it can also be converted by methanotrophic bacteria, to yield, e.g., the biodegradable materials like PHB. Bio-based polymers would be more eco-friendly choice, as they can be made from renewable carbon sources and may contribute to climate change mitigation. Bioplastics might be an alternative to conventional fossil-based plastics, particularly when they can be recycled.

Ceramic materials offer a variety of desirable material properties, but due to being particularly hard and brittle, are challenging to machine in subtractive processes. Additive manufacturing of ceramics parts requires costly machines and raw materials, limiting the use of additively produced ceramic parts to the professional realm. Fused Filament Fabrication (FFF) has become a widespread additive manufacturing technology, due to low cost of machines and materials (typically polylactic acid (PLA) and ABS)). This paper addresses the suitability of the FFF process to manufacture ceramics parts cost-effectively.

Complex structures and a high level of customization in architecture and construction industries require the usage of industrial robots for milling or additive manufacturing applications. Due to economic aspects and the intensive research on robot machining, conventional machine tools are increasingly superseded for specific tasks by industrial robots. However, assembling errors during the manufacturing process and low structural stiffness of industrial robots are still main reasons for inaccuracies of robotic based machining. This paper presents a comparison between industrial robots and cnc machine tools and evaluates their strength and weaknesses. Furthermore, recently published works considering robot calibration and offline compensation strategies in order to increase the absolute and machining accuracy are presented. Finally, the adaption of an existing robot machining process chain with additional components underlines the potential of robots for machining tasks.

State-of-the-art 3D-printing with metal filaments based on the Fused Filament Fabrication (FFF) process is discussed in this paper, by a literature review and own printing tests. Commercially available metal filaments (composites with metal powder content) are flexible enough to be processed on a low budget 3D-printer and, by debinding and sintering the produced objects, it is possible to reach 80% and more of the mechanical strength of machined metal counterparts. A market research for available metal filaments from different sellers was conducted. The filament in question is compared by price and its printing and sintering properties, and particularities have been outlined. The prices for these metal filaments range from about €100/kg to €500/kg, with one exception: a filament which contains titanium is being offered for nearly €1500/kg. Objects have been successfully printed from a purchased, sinterable metal filament (“Ultrafuse® 316L” filament from BASF containing steel (DIN 1.4404, X 2 CrNiMo 17 13 2)) with the use of a low-budget 3D-printer to verify its feasibility. The testing model for printing was a “benchy”, which is a common test object in the hobby area of 3D-printing. Physical adjustments which had to be made to the printer itself and the printing parameters, as well as the difficulties faced while printing, are described in detail. This paper should serve hobbyist makers in doing the transition from plastics FFF to metal FFF to allow them to produce more durable parts.

Since the last decade, the industry of 3D printing is sharply on the rise. A new trend in the manufacturing of polymers deals with the production of upscaled products that exceed an object size of one cubic meter. This trend has still some challenges to overcome that aim to reduce the costs and the process time in order to enable a more economical production. A method called Fused Granular Fabrication (FGF) uses thermoplastic pellets as a working material. FGF faces the challenges of upscaled 3D printing. Plastic pellets come to a friction of the cost of filament rolls for typical 3D printing application. Furthermore, they offer a greater variety of materials and can be refilled constantly during the printing process, which guarantees a production of almost unlimited big 3D prints. This paper deals with an industrial robot application of the UAS Technikum Wien that is equipped with a simple pellet extruder. The process parameters for good 3D prints were evaluated in a series of tests. All the tests were performed with Ingeo 4034D PLA pellets. A developed cooling system could speed up the process time by 17% for qualitative 3D prints. This work shows the potential of the FGF method and focuses on the build of an upscaled vase with a height of one meter. It was found out that the system still has an insufficient print speed for larger plastic objects, because of the slow feed rate of the used pellet extruder. As a result, a new research started for an alternative pellet extruder. Some of the potential extruders were good substitutes to produce upscaled 3D prints but they come to a high cost. As a self-made solution a new concept for a pellet extruder was designed. The introduced concept should achieve a material flowrate above 2 kg/h, to enable the 3D print of upscaled plastic products within a single day. As industrial robots are already an essential part of our modern industry 4.0, this technology allows it to easily produce individual products with existing systems. The designed pellet extruder can be mounted and exchanged smoothly to make the modern production more efficient.