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The qualification process of pressure vessels in general is subject to governmental restrictions. Thus, introducing additive manufacturing (AM) components to the market is challenging due to incomplete standardization. To increase component safety and trust, predetermined points of failure can be integrated by design using direct manufacturing methods. A predetermined point of failure using a surface notch is one option to avoid dangerous part failure (e.g. explosion) and increase safety. For implementation, a design approach with experimental proof of concept is striven to guide manufacturers and demonstrate the behavior of the material and the component as a whole. Finite element analysis is used for investigations on the influence of surface notch geometries applied to wall structures on structural stress super-elevation. Analytical strength assessment using FKM guideline and experimental validation of PBF-LB/M-manufactured specimen behavior by static axial tensile and burst testing is carried out. Fracture surface and plastic elongation evaluation using light microscopy and 3-D surface scanning clarify the material behavior. The analytical and experimental approval of an integrated predetermined point of failure for static overload is achieved without reducing the maximum burst pressure value. The integration fulfills all theoretical requirements for structural strength. All tested specimens meet the expectations regarding static strength and failure behavior. As expected, component elongation decreases using surface notches for failure provocation. Results lead to a proposed guideline for the application of an integrated predetermined point of failure by the use of a surface notch.

Bislang limitiert ein mangelnder Automatisierungs- und Digitalisierungsgrad den wirtschaftlichen Erfolg der additiven Serienproduktion. Bedingt durch Spezifika wie die gemeinsame Fertigung von Bauteilen im Batch liegt eine Herausforderung in der Produktnachverfolgung. Der Beitrag zeigt Ansätze der Rückverfolgbarkeit und anhand eines Praxisbeispiels, wie passende Auto-ID-Systeme systematisch ausgewählt werden und in Kombination die notwendige Datenbasis für die Produktionssteuerung bereitstellen können. A low level of automation and digitization still limits the economic success of additive series production. Due to specifics such as the joint manufacturing of components in batches, a central challenge is product tracking. This paper provides insights into traceability approaches and uses a practical example to demonstrate how suitable auto-ID systems can be systematically selected and used in combination to provide the necessary data base for production control.

The main objective of ISO/TC 261 is to standardise the processes of Additive Manufacturing, the process chains (Data, Materials, Processes, Hard- and Software, Applications), test procedures, quality parameters, supply agreements, environment, health and safety, fundamentals and vocabularies. This section provides readers with news regarding standardisation efforts of ISO/TC 261. Further up-to-date information regarding recently published documents, such as new standards, revised standards, the status of standards can be found in the ISO/TC261 webpages: https://www.iso.org/committee/629086.html and the committee webpages: https://committee.iso.org/sites/tc261/home/news.html.

The main objective of ISO/TC 261 is to standardise the processes of Additive Manufacturing, the process chains (Data, Materials, Processes, Hard- and Software, Applications), test procedures, quality parameters, supply agreements, environment, health and safety, fundamentals and vocabularies. This section provides readers with news regarding standardisation efforts of ISO/TC 261. Further up-to-date information regarding recently published documents, such as new standards, revised standards, the status of standards can be found in the ISO/TC261 webpages: https://www.iso.org/committee/629086.html and the committee webpages: https://committee.iso.org/sites/tc261/home/news.html.

Im Vergleich zur konventionellen Fertigung ist der schichtweise Bauteilaufbau der additiven Fertigung durch eine höhere Flexibilität gekennzeichnet. Die auch als 3D-Druck bezeichneten additiven Fertigungsverfahren erlauben die Herstellung mehrerer unterschiedlicher Komponenten in einem Bau- beziehungsweise Druckvorgang. Im Rahmen der Produktionsplanung und -steuerung gilt es daher, eine ressourcenoptimierte Zusammenstellung für die Bauvorgänge zu ermitteln. Compared to conventional manufacturing, the layer-upon-layer principle of additive manufacturing is characterized by greater flexibility. The additive manufacturing processes, also known as 3-D printing, enable the production of several different components in a single printing process. In the context of production planning and control, it is therefore necessary to determine a resource-optimized composition for the build processes.

Multi-material additive manufacturing by laser-based powder bed fusion (PBF-LB) combines the advantages of additive manufacturing (AM), such as the ability to build complex structures, with the capability to create an arbitrary material distribution in one manufacturing process. This paper presents the implementation of a multi-material mechanism in a mono-material PBF-LB system. Therefore, the multi-material process and the new powder deposition mechanism are introduced. Special attention is paid to the required process steps of powder recoating and powder removal. To gain further insight into the multi-material process, dependencies between the powder removal and the manufacturing quality are described. Furthermore, the required equipment and the current challenges of multi-material additive manufacturing are highlighted. In addition, results of the material combination consisting of the tool steel 1.2709 and the copper alloy CW106C are shown and discussed.

Für Cyber-physische Produktionssysteme entwickeln Fertigungsplaner modular, skalierbare Fertigungszellen. Die alternativen Zellkonfigurationen sind jedoch aufgrund diverser Einflüsse in der kundenindividuellen Massenfertigung aufwändig zu bewerten. Zur virtuellen Absicherung wird daher ein simulationsgestützter Modellierungs- und Bewertungsansatz vorgestellt. Der Ansatz besteht aus einem methodischen Vorgehen mit einem zugrundeliegenden agentenbasierten Simulationsmodell.

Additive Manufacturing (AM) allows the manufacturing of functionally graded materials (FGM). This includes compositional grading, which enables the allocation of desired materials corresponding to local product requirements. An upcoming AM process for the creation of metal-based FGMs is laser-based powder bed fusion (PBF-LB/M) utilized for multi-material manufacturing (MM). Three-dimensional multi-material approaches for PBF-LB/M are stated to have a manufacturing readiness level (MRL) of 4 to 5. In this paper, an advancement of multi-material technology is presented by realizing an industry-relevant complex part as a prototype made by PBF-LB/M. Hence, a multi-material injection nozzle consisting of tool steel and a copper alloy was manufactured in a continuous PBF-LB/M process. Single material regions showed qualities similar to the ones resulting from mono-material processes. A geometrically defined transition zone between the two materials was achieved that showed slightly higher porosity than mono-material regions. Nevertheless, defects such as porosity, cracks, and material cross-contamination were detected and must be overcome in further MM technology development.

In this review paper, the authors investigate the state of technology for hybrid- and multi-material (MM) manufacturing of metals utilizing additive manufacturing, in particular powder bed fusion processes. The study consists of three parts, covering the material combinations, the MM deposition devices, and the implications in the process chain. The material analysis is clustered into 2D- and 3D-MM approaches. Based on the reviewed literature, the most utilized material combination is steel-copper, followed by fusing dissimilar steels. Second, the MM deposition devices are categorized into holohedral, nozzle-based as well as masked deposition concepts, and compared in terms of powder deposition rate, resolution, and manufacturing readiness level (MRL). As a third aspect, the implications in the process chain are investigated. Therefore, the design of MM parts and the data preparation for the production process are analyzed. Moreover, aspects for the reuse of powder and finalization of MM parts are discussed. Considering the design of MM parts, there are theoretical approaches, but specific parameter studies or use cases are not present in the literature. Principles for powder separation are identified for exemplary material combinations, but results for further finalization steps of MM parts have not been found. In conclusion, 3D-MM manufacturing has a MRL of 4–5, which indicates that the technology can be produced in a laboratory environment. According to this maturity, several aspects for serial MM parts need to be developed, but the potential of the technology has been demonstrated. Thus, the next important step is to identify lead applications, which benefit from MM manufacturing and hence foster the industrialization of these processes.

During the metal-based additive manufacturing process “laser-based powder bed fusion“ (Short: PBF-LB/M) even minor deviations from the required process conditions, e.g. changes in the layer thickness or a reduction in the inert gas flow, can lead to defects and thus negatively affect the quality of the components. In the field of non-destructive testing, heat flow thermography is an established method for detecting defects close to the surface. In this paper, a method to investigate the potential of non-destructive testing by means of a laser as an excitation source for active thermography and the results for the material 1.4404 are presented.

Kurzfassung Die Prozesskette der additiven Fertigung bedarf fur die industrielle Serienproduktion einer Produktivitatssteigerung. Eine entsprechende Technologiekettenplanung wird jedoch aufgrund de...

We demonstrate that the output statistics of a quantum annealing protocol run on D-Wave 2000Q can be explained by static disorder garnishing an otherwise ideal device hardware. A Boltzmann-like distribution over distinct output states emerges with increasing problem size, and significantly reduces the chances for a correct identification of the sought-after optimal solutions.

Metal powder cross-contaminations are a hindrance in powder-based additive manufacturing (AM). Foreign particles can enter the powder feedstock when two different materials are processed on a single machine – either successively through material changes or simultaneously during multi-material AM. In order to evaluate the criticality of named powder impurities, this study investigates the influence of foreign particle inclusions on part quality during laser powder bed fusion of a material combination commonly processed in multi-material AM: copper alloy CW106C particles in maraging steel 1.2709 feedstock. Different contamination levels are examined regarding metallurgical structure, defect formation, and mechanical strength. It is observed that coppery inclusions are dissolved and do not cause cracks, porosity or other defects below three particle percent. Furthermore, ultimate tensile strength and fracture elongation show a slight negative trend for increasing contamination levels.

Man kann zwei Auffassungen über die normative Grundlage einer intergenerationellen unternehmensethischen Theorie (IUET) unterscheiden, akteursvariante und akteursinvariante IUET. Jede von ihnen ist mit jeweils einer spezifischen Schwierigkeit konfrontiert: Akteursvariante IUET sind dem inversen Nichtidentitätsproblem (INIP) ausgesetzt, akteursinvariante IUET dem Problem des moralischen Verdrängungseffekts (MVEP). Diese Schwierigkeiten sind besonders hartnäckig, wenn man in einem nicht-reduktionistischen Rahmen bleibt und Unternehmen als eigenständige moralische Akteure versteht, deren Verantwortung sich nicht auf die Verantwortung individueller Akteure oder übergeordneter Institutionen zurückführen lässt. Das könnte dafürsprechen, in intergenerationellen Kontexten eher einen reduktionistischen Ansatz zu verfolgen.

The in-situ integration of sensors into additive manufactured (AM) components is becoming increasingly important and moving into the focus of current research. However, manual sensor integration during the metal- and laser-based powder bed fusion (LPBF) process is usually associated with long process downtimes, the loss of the shielding gas atmosphere and a change in component temperature. The resulting effects are e.g. changed mechanical properties. Therefore, one way to avoid these effects is presented by automated sensor integration. A procedure for the design of kinematics to meet the requirements is presented and experimentally validated. As a result, a functional automation unit in an LPBF plant is presented.

During the metal-based additive manufacturing process “laser-based powder bed fusion” (short: PBF-LB/M) interruptions can occur throughout the build job. These interruptions may be planned to produce hybrid parts, e.g., to insert components or electronics into the part or to adapt the manufacturing process itself. But interruptions can also be fault-induced, which can occur due to system failures, insufficient available powder quantities or poor component and process characteristics. Depending on duration, temperature and ambient atmosphere, these interruptions can have major influences on the component’s properties. The effects of a process interruption on the microstructure and the tensile properties for the material AlSi10Mg are to be presented within this work. In addition the impact of process interruptions on the mechanical properties of the tested components is shown.

Multi-material additive manufacturing by laser powder bed fusion enables arbitrary material composition in components and thus opens new design possibilities. During the manufacturing process utilized powders are mixed and arising cross-contaminations are a hindrance for powder reuse. This paper investigates the possibility to process binary metal powder mixtures of different particle size distributions, which can be sorted and recycled by screening. Two different material combinations are processed over three multi-material manufacturing cycles and powder purities in the range of parts per thousand foreign particles can be achieved. Furthermore, material flow is calculated and general applicability of the recycling process is evaluated.

The main objective of ISO/TC 261 is to standardise the processes of Additive Manufacturing, the process chains (data, materials, processes, hard- and software, applications), test procedures, quality parameters, supply agreements, environment, health and safety, fundamentals and vocabularies. This section provides readers with news regarding the standardisation efforts of ISO/TC 261. Further up-to-date information regarding recently published documents, such as new standards, revised standards, the status of standards can be found in the ISO/TC261 webpages: https://www.iso.org/committee/629086.html and the committee webpages: https://committee.iso.org/sites/tc261/home/news.html.