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Selective laser sintering (SLS) is currently in transition to the production of functional components. However, the ability to apply it is confronted with new requirements for reliability and reproducibility. Therefore, an in-depth understanding of aging processes in polymers is essential. Regarding material traceability as well as defective component identification with subsequent cause tracing, the application of a material-inherent marking technology represents a solution. SLS in combination with modified polymers as a marking technology proves to be an efficient opportunity to produce reproducible and high-quality components due to an increased understanding of the process. Based on a selection of modified polymers for use in SLS, which were characterized in part I of the study, this work focuses on the experimental validation of the result. The influence of modified polymers on materials and component properties and the SLS process's influence on the traceability of modified polymers are examined. Intrinsic and extrinsic material properties as well as mechanical properties, surface quality and sinter density are analyzed. No discernible influences of the modified polymers on the investigated properties could be observed and the traceability of the modified polymers could also be confirmed in the aged powder and component using mass spectroscopy. [ABSTRACT FROM AUTHOR]

Selective laser sintering (SLS) with polymers is currently at the transition stage for the production of functional components and holds great potential to revolutionize conventional production processes. Nevertheless, its application capability is confronted by newly imposed requirements regarding reliability and reproducibility. To safeguard these requirements, a deeper process understanding of material aging mechanisms in polymeric materials is needed. In order to enable the traceability of the materials as well as the identification of defective components with subsequent tracing of the cause, the use of a material marking process represents an alternative. SLS in combination with material marking is proving to be an efficient option for reproducible, high-quality manufacturing based on an increased understanding of the process. In this study, the idea of a marker-based traceability methodology for the purpose of process optimization is presented. Fundamental to the subsequent experimental investigation of the marking agent suitability, this work first focuses on the systematic selection of a suitable marking agent for use in SLS. Based on an analysis of the sinter material to be marked and a set of marking technologies, as well as using the selection methodology, the modified polymer marking technology was evaluated as the most suitable marking technology. [ABSTRACT FROM AUTHOR]

Incremental Manufacturing (IM) is a hybrid-manufacturing concept where standardized base parts are produced in large volume production first, then assembled and finalized by additive and subtractive manufacturing. The concept allows for a flexible combination of different manufacturing processes. These new possibilities result in a high degree of freedom in both parts design and process planning, which must be used purposefully and restricted in a manageable way with regard to production-related restrictions. This paper presents an approach for evaluating different production routes of an IM designed part. [ABSTRACT FROM AUTHOR]

The demand for customised products leads to an increasing diversity of variants and batch sizes in production. Therefore, established high volume production technologies have become less profitable. This loss results primarily from high product-specific investments in mould-based manufacturing systems such as injection moulding and sheet metal forming whose amortisation is challenged by smaller batch sizes. The increasing number of components in multi-material design, especially from metal and plastics, calls for flexible production technologies. This paper introduces a new robot-based process chain for metal-plastic parts to close the existing gap between manual production of small batches and mould-based high volume production. The idea is to combine surface treatments with additive and subtractive manufacturing processes in a single workspace implementing an incremental process chain to realise a scalable production system. This will increase the manufacturing flexibility for customised products and reduce the cost per unit. As a first step in the process chain, the surface of a pre-produced metal part is structured for mechanical interlocking and high strength joining. Subsequently, an additive process is used to directly apply a plastic section onto the pre-structured metal part, thus producing a hybrid component. Finally, the hybrid component is machined to add individual holes or pockets and to finish the surface of the additively manufactured area. This paper presents a scalable process chain for metal-plastic components as well as concepts for its technological implementation. Furthermore, first experimental results from the fabrication of a metal-plastic part using additive and conventional processes are presented. [ABSTRACT FROM AUTHOR]

Abstract Incremental Manufacturing is a hybrid-manufacturing concept where standardized base workpieces are made in large volume production first and finalized by additive manufacturing. The concept reduces the need for product-specific molds and tools, enabling a multi-scale production - the flexibility to scale product variants and sizes as well as production volume. This paper presents an approach to reduce the arising complexity from the new design freedom of Incremental Manufacturing in an early component design phase. For this manufacturing, material and process models will be merged to support the multi-dimensional decision-making process during the design phase of multi-material parts for Incremental Manufacturing. [ABSTRACT FROM AUTHOR]

Additive manufacturing meets the demand for highly customized and flexible production. However, the physical limitation of the material application rate causes that large volume production of such workpieces is not attractive yet. In order to push additive manufacturing towards large volume production, the impact of this limitation has to be minimized while the advantages have to be maintained. For this purpose, it is proposed in this article to combine partial additive manufacturing with other production technologies. In such a production concept, standardized base workpieces are made in large volume production first and then finalized by additive manufacturing. The finalization step adds the variant specific key features to the workpiece. This proposal is detailed by discussing the suitability of specific workpieces and outlines of the processing route. An experimental feasibility study of this principle is reported, where Fused Deposition Modeling is used to add geometric features to a base workpiece. This case study includes the development of a robot-based setup for the deposition of material with 6 degrees of freedom. This case study is used to illustrate and discuss the fundamental aspects of the conjunction of additive manufacturing with other production processes. [ABSTRACT FROM AUTHOR]