Additive Fertigung

By integrating specific material properties through the manufacturing process Selective Laser Melting (SLM) into a topology optimization, the product engineer can be supported by simulation in the design process. For this purpose, a topology optimization method is being developed which takes the process-specific material properties of the SLM into account during the optimization process. This method is part of a project funded by the German Research Foundation (DFG). In this article, the influence of these specific material properties on the design is presented.

In this paper, the creation of strength and stiffness-adapted structural nodes using the numerical simulation method of topology optimization is presented. The resulting node is transferred into a robot path planning by means of CAD/CAM software and manufactured with wire arc additive manufacturing (WAAM) with the GMAW process using the welding filler material G4Si1.

Current advances result in increasingly complex production programs. Through combination of additive manufacturing and Industry 4.0, new elements can be formed and - as a whole - enable to economically manufacture the above mentioned programs. The Bionic Smart Factory 4.0 provides a framework, structuring them in terms of relation and interaction. Their development and implementation is being promoted through their evaluation against the determinants of complex production programs.

Metal-cutting manufacturing companies constantly demand for highly efficient process layouts which can particularly be achieved by the utilization of application optimized special tools. Conventional methods for the manufacturing of cutting tools are subject to restrictions, particularly with respect to the inner and outer shape design. At this point, additive manufacturing offers a substantial innovation potential. Through the buildup by layers, design limits of conventional methods are repealed and the production of complex and individual structures is feasible. Against the background of these process-specific potentialities, the iWFT and associated research and industry partners are developing a process chain for additive manufacturing of tungsten carbide cutting tools in the framework of the joint research project PraeziGen.

Architectural design is traditionally limited by the availability of fabrication tools and increasing loan costs. Especially in concrete industries this has a great effect due to the intensive need of manual craftsmanship at the production of formwork. By introducing additive fabrication processes and methods of Industry 4.0 as advanced inspection procedures new design limits can be discovered. To produce large scale concrete elements with high surface qualities and high accuracy at joints in short time hybrid fabrication processes can be a solution. At TU Braunschweig a new generative method is investigated where concrete is sprayed on an adaptive formwork and graded surfaces can be generated.

The proliferation of technological innovations in additive manufacturing is accompanied by an increasing awareness of sustainability. In order to achieve an adequate investment methodical support is needed. A set of indicators for sustainable production represents the performance of a technology. Since an evaluation of technologies is subjective individual preferences of decision makers have to be taken into account. Hence, the multiple-criteria decision analysis methodology PROMETHEE is applicable in this context.

The additive production processes are increasingly developed from Rapid Prototyping to Additive Manufacturing (AM), which provides an outstanding technological and economic potential for a variety of industries. Particularly in the area of varied small series production these technologies offer significant advantages in terms of reducing component weight, the integration of additional functions and the production of complex geometries or individual components. Due to the juvenileness of the technology there is a lack of knowledge concerning the technology itself, its possibilities and application potentials in many companies. In addition the costs are often regarded as a critical success factor for the widespread use of the technology. In particular the smart use of AM will affect the positive impact on the future economic use of a product throughout its life cycle.

The increasing complexity of technical components and shorter product life cycles make high demands on the flexibility and the efficiency of production processes. Additive manufacturing processes comply with this requirement profile. So far, these methods particularly in the desktop prototyping and manufacturing are common. The undisputed high potential for individual production of small batches by means of additive manufacturing processes is so far due to the low reproducibility of the manufactured components not been fully utilized in terms of a rapid manufacturing. Especially powder- and beam-based additive manufacturing technologies offer in terms of recoverable component strengths with both metallic and polymeric materials have a promising range of applications. The basic scientific study of this process is the goal of the Collaborative Research Centre 814 Additive Manufacturing (SFB 814). In the following article, aims and initial results from the SFB 814 are shown.