Many users relate additive manufacturing (AM) directly with fast and high-quality prototyping and manufacturing. Nevertheless, already within the different printing techniques there are significant printing time differences for the same polymer printed objects. For AM, there are currently two main known methods to three-dimensional (3D) print objects: One is the vat polymerization process using liquid crystal display (LCD) polymerization, also known as masked stereolithography (MSLA). The other is material extrusion, known as fused filament fabrication (FFF) or fused deposition modeling. Both processes can be found in the private sector (desktop printers) or in industry. The FFF and MSLA processes apply material layer by layer to 3D print objects, but both processes are different in their printing techniques. The different printing methods result in different printing speeds for the same 3D printed object. Geometry models are used to investigate which design elements affect the printing speed without changing the actual printing parameters. Support and infill are also taken into account. The influencing factors will be shown to optimize the printing time. With the assistance of the different slicer software, the influence factors were calculated and the different variants are pointed out. The determined correlations help to find the suitable printing technique to make optimum use of the printing performance of both technologies.

Three-dimensional (3D) printing has attracted a great deal of attention in recent years in many application fields, for example in the aerospace, construction, industries, art, education, protection, security and medical fields. Some of these application fields of 3D prints depend on the adhesion of imprint polymers on textiles. Adhesion is the tendency of unlike surfaces to cling to one another due to the intermolecular and interatomic interaction of the two surfaces. This study investigated how water and oil resistant treatment of woven fabrics influence on the adhesion strength of 3D prints. The prints were produced from Onyx using Markforged Mark Two 3D printer on Fluorocarbon (FC) treated and untreated woven fabrics. The different printed samples were subjected to a 180° peel test for the full detachment of the prints from the fabric. The result showed that the treatment of the woven fabrics had a significant influence on adhesion force. Further, the results revealed that the treated woven fabric limited the penetration and passage of the melted Onyx through the fabric which gave low adhesion strength between the print and the fabric. The microscopic analysis revealed that the back of the detached 3D prints from the untreated woven fabrics contained many fibers still attached because of the high adhesion strength.

Three-dimensional (3D) printing has been attracting a great deal of attention in recent years in many application fields, for example, in the aerospace, construction, industry, art, education, protection, security, and medical fields. Printing methods, materials, and parameters influence the performance quality and determine the application sector of 3D prints. In this study, the print parameters are used as independent variables to investigate the compression strength of 3D printed cubes/cubes. The prints were produced by considering infill type, infill percentages, vertical wall, horizontal contours, and dimensions of items as the product parameters. The different printed samples were subjected to atmospheric conditions for 24 hours at (20 ± 1)°C temperature and (65 ± 2)% relative humidity. The samples were then subjected to a cyclic compression test with an indentation depth of 5 mm. The compression force to the planned displacement was measured. As seen from the results, the print parameters investigated in this research significantly influence the compression force and determine the performance of 3D prints according to the application sector. Although all parameters significantly influence the compression force of 3D prints, the magnitude and level of performance are different. Vertical walls relatively withstand high compression force while filling type gives soft and weak products with a relatively low mass. However, the choice of different pressure parameters can influence the compressive strength. With this knowledge, it will be possible in the future to print human soft tissues with a specific compressive strength using the FDM printing process.

Protective clothing, worn for example by police, ambulance and private security services, has the task of protecting against weapon attacks and is becoming increasingly important. International standards specify test methods to ensure the protective effects and classes, but the protective surfaces or the wearing comfort are not defined more detailed in the standards. In the study, a new measurement method is developed and presented for determining the percentage of protected body parts by a stab protective vest. After considering various approaches, the combination of scanned 3D/4D body data and appropriate processing turned out to be the most suitable. With the developed method, the projection of protective surfaces onto scanned bodies or avatars is possible. This study helps defining a key indicator of the protected areas and therefore makes different vest variants more comparable.

Adhesion between additively printed elements on textiles is one of the most important quality characteristics. Applied elements must form very good adhesion with the textile substrate in order to produce functional textiles. The request for non-planar printing directly on textiles is growing, especially in the fields of orthopaedic engineering and protective clothing. This new printing technique can open up new areas of application. For such a production of non-planar elements on textiles, new test methods have to be developed, as the current adhesion tests (180° peel test) are not applicable to non-planar prints on textiles. For non-planar additive printing on textiles, a cylindrical print bed for a fused filament fabrication printer was developed and modified accordingly in the first step. In the next step, a new measurement method was developed to investigate the adhesion between the textile and the non-planar three-dimensional-printed element. The study shows the challenges and the adhesion differences of non-planar printed objects on pre-stretched textiles on a cylindrical print bed. Several factors influencing adhesion were identified. The alignment of the printing nozzle to the textile substrate is the key factor influencing adhesion. The alignment also has a significant influence on the visual print quality.