With Additive Manufacturing (AM), manufacturing companies have the potential to develop more geometrically and functionally complex products. Design for AM (DfAM) has become an expression implying the need to design differently for the AM process, compared to for conventional, usually "subtractive" manufacturing methods. There is a need to understand how AM will influence the product development process and the possibilities to create innovative designs, from the perspective of the product development engineer. This paper explores the expected influence of AM on the product development process in a space industry context. Space industry is characterized by small-scale production, and is increasingly cost-oriented. There is a general belief that AM could pave the way for more efficient product development. Three companies have been studied through interviews, observations and workshops. Results show that engineers' expected implications of introducing AM in the space industry are: The involvement and influence of customers and politics on innovativeness; the need for process understanding and usage of new tools for DfAM-thinking; the need for qualification of AM processes.

Additive Manufacturing (AM) has the potential to remove boundaries that traditional manufacturing processes impose on engineering design work. The space industry pushes product development and technology to its edge, and there can be a lot to gain by introducing AM. However, the lack of established qualification procedures for AM parts has been highlighted, especially for critical components. While the space industry sees an advantage in AM due to expensive products in low volumes and long lead-times for traditional manufacturing processes (e.g. casting), it also acknowledges the issue of qualifying mission critical parts within its strict regulations. This paper focuses on the challenges with the qualification of AM in space applications. A qualitative study is presented where conclusions have been drawn from interviews within the aerospace industry. The results highlight important gaps that need to be understood before AM can be introduced in critical components, and gives insight into conventional component qualification.

In recent years, reducing cost and lead time in product development and qualification has become decisive to stay competitive in the space industry. Introducing Additive Manufacturing (AM) could potentially be beneficial from this perspective, but high demands on product reliability and lack of knowledge about AM processes make implementation challenging. Traditional approaches to qualification are too expensive if AM is to be used for critical applications in the near future. One alternative approach is to consider qualification as a design factor in the early phases of product development, potentially reducing cost and lead time for development and qualification as products are designed to be qualified. The presented study has identified factors that drive qualification activities in the space industry and these “qualification drivers” serve as a baseline for a set of proposed strategies for developing “Design for Qualification” guidelines for AM components. The explicit aim of these guidelines is to develop products that can be qualified, as well as appropriate qualification logics. The presented results provide a knowledge-base for the future development of such guidelines.

The use of metal Additive Manufacturing (AM) has increased in recent years with potential benefits for novel design solutions and efficient manufacturing. In order to utilise these potentials, engineers need to address uncertainties related to product design and the AM process. This paper presents a design process utilising product specific AM Design Artefacts (AMDAs) to assess uncertainties identified during design. The process emphasises the importance of concurrently developing the product and AM knowledge. Based on a research collaboration with industry, three case studies describe the use of this process in the development of products for AM. In total, six different types of AMDAs show how AM-related uncertainties are resolved to provide confidence in design solutions and manufacturability. The contributions of this paper are: (i) a design process where AMDAs are used as support in evolving and defining an AM design specification, (ii) an example of how DfAM is practiced in industry and of typical AM uncertainties that are encountered and addressed, and (iii) an example of how collaborative research can facilitate new knowledge for both industry and academia. The practical implication is a DfAM process for engineers to use and adapt according to existing AM knowledge.

Qualification of components and processes is crucial for implementing additive manufacturing (AM) as part of a company’s manufacturing process portfolio. Currently, extensive research is ongoing in industry and academia to understand the capabilities and limitations of AM in order to enable qualification. For critical structural components, understanding the impact of the AM process and material on mechanical properties is essential. While an overall logic for qualification of AM parts is sought for, the complexity of these multidisciplinary end-to-end manufacturing processes requires comprehensive knowledge to be built in the pursuit of such a logic. As part of this work, GKN Aerospace is using demonstrator hardware to mature the AM process.

While early expectations on AM often considered it as a universal manufacturing process, the hype has now subdued and it is generally accepted that AM is not suitable for all products. However, in the cases where AM is a good match, it has potential for cost and lead time reduction, while maintaining performance and reliability. GKN has identified liquid rocket engine turbines with highly loaded parts, complex designs, and that are manufactured in low volumes, as a perfect fit for AM. Currently, GKN is designing a new ultra-low-cost turbine demonstrator relying on three objectives; (1) low number of components, suppliers and processes, (2) robust design, and (3) efficient manufacturing. The fully laser powder bed fusion (LPBF) manufactured turbine demonstrator scheduled for engine test in 2020, is an important step in the GKN AM technology demonstration for highly loaded aerospace parts. The verification and demonstration of the AM turbine rests on three pillars; (i) material data, (ii) analysis, and (iii) hardware. Analytical verification using AM material data is the foundation in the verification of the AM turbine. To support this, material testing is an important part of verifying the AM material, as is component testing to check design margins in relation to prediction. Additional testing includes traveler specimens or structures built simultaneously as the full part. Non-destructive inspection of components and travelers verify material quality, and destructive inspections validate the results from non-destructive inspections.

This paper presents the use of this verification approach on a LPBF turbine, where correlation of material data, component testing and inspection to analyses are discussed. Furthermore, conclusions are drawn on future needs for the development of a qualification logic for serial production AM hardware.

Additive Manufacturing (AM) provides several benefits for aerospace companies in terms of efficient and innovative product development. However, due to the general lack of AM process understanding, engineers face many uncertainties related to product qualification during the design of AM components. The purpose of this paper is to further the understanding of how to cope with the need to develop process understanding, while at the same time designing products that can be qualified. A qualitative action research study has been performed, using the development of an AM rocket engine turbine demonstrator as a case study. The results show that the qualification approach should be developed for the specific application, dependent on the AM knowledge within the organisation. AM knowledge is not only linked to the AM process, but to the complete AM process chain. Therefore, it is necessary to consider the manufacturing chain during design, and to develop necessary knowledge concurrently with the product in order to define suitable requirements. The paper proposes a Design for Qualification framework, supported by six design tactics. The framework encourages proactive consideration for qualification and the capabilities of the AM process chain, as well as the continuous development of AM knowledge during product development.