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The AMHUB vision is is to provide additive manufacturing as-a-service for customers needing high quality parts. In AMHUB pre-qualified service providers work efficiently together under a network of additive manufacturing HUBs to provide the required additive manufacturing and delivery end-to-end service for customers with one stop- shop principle.This report describes the AMHUB visionary concept created based on the collected key insights from company discussions.

Laser powder bed fusion additive manufacturing is used for demanding applications in industries such as aerospace. However, machine-specific, optimized process conditions and parameters are required to assure consistent part quality. In addition, differences in supplied powder can cause variation in the mechanical properties of the final parts. In this paper, the variability in mechanical properties of 316L stainless steel produced with two different laser powder bed fusion machines from two different powder batches was studied by producing an identical set of tensile and impact toughness test specimens. The samples were subjected to stress-relieving, solution annealing and hot isostatic pressing to assess the effectiveness of standardized heat-treatments in reducing variation in the mechanical properties of the built parts. Porosity, microstructure, tensile properties, and impact toughness of the specimens were measured to study the effect of changing the material, machine, and heat treatment. The maximum differences observed between the studied machine-powder combinations were approximately 7% for tensile properties and approximately 20% for impact toughness. HIP reduced the variability in all other studied properties except elongation. All the specimens fulfil the minimum requirements set in ASTM F3184-16 for AM 316L.

The report summarises the results of the New Business From Digital Spare Parts project (DIVALIITO), managed and implemented by VTT and Aalto University during the years 2018-2020. In the project, methods for identification of 3D printable parts from the spare parts libraries were developed, and information available on materials for additive manufacturing were compiled, produced and compared with the conventional manufacturing materials and methods. New spare part concepts such as smart spare parts with embedded intelligence were investigated, and the connections of the process steps of the whole manufacturing chain of the digital spare part were clarified, especially from the workflow, quality control and automation perspectives. The report is a compilation of results and it contains links to original documents where the results are presented more widely.

The purpose of this paper is to verify the conceptual benefits of the implementation of additive manufacturing (AM) in spare part supply chains from the point of view of industry. Focus group interviews consisting of five sessions and 46 experts in manufacturing were conducted for this study. The focus group interviews served to identify the issues in the adoption of digital spare parts (DSP) and to expand on the available literature. The benefits found in the reviewed literature were partially verified by the participants but certain limitations, such as the excessive need of post processing, supplier quality parity, and ICT inadequacies, were presented that were absent or not highlighted in literature. The information gathered from the participants made it possible to create a realistic model of a digital spare part distribution network. According to the focus group interviews, digital spare parts could be deployed immediately for a specific type of product in the long tails of company spare part catalogues. However, improvements in AM, company ICT infrastructure, and 3D model file formats need to be achieved for a larger deployment of DSP.

Metallien AM-prosessin (jauhepetimenetelmä) tuotannolliseen käyttöönottoon ja tuotantoon integroimiseen liittyy paljon erilaisia työvaiheita. AM-laitehankintaa suunniteltaessa onkin olennaista ottaa huomioon kaikki ne työvaiheet, jotka tarvitaan haluttujen osien valmistamisessa. Lähes aina tarvitaan tiettyjä työvaiheita jauhepetivalmistuksessa kuten tukien poisto, mutta toisaalta osa työvaiheista määräytyy sen mukaan, millaisia vaatimuksia lopputuotteille on asetettu mm. pinnanlaadun ja mittatarkkuuden suhteen. Tässä raportissa kuvataan jauhepetimenetelmällä tapahtuvan metallien lisäävään valmistukseen liittyvät työvaiheet. AM-prosessin työvaiheet voidaan jakaa ennen varsinaista valmistusprosessia tapahtuviin ohjelmointiin ja suunnitteluun liittyviin tehtäviin, itse AM-valmistukseen sekä valmistuksen jälkeisiin toimenpiteisiin. Varsinaiseen valmistusvaiheeseen liittyvät olennaisesti materiaalien kuten jauheiden hallinta sekä itse prosessiin liittyvät tekijät. Varsinkin metalliosien AM-valmistukseen liittyy suuri joukko erilaisia jälkikäsittelyprosesseja, joista tarpeelliset valitaan käytettyjen materiaalien ja valmistusprosessin sekä valmistettavien osien vaatimusten mukaan. Laadunvalvonta on myös tärkeä osa AM-valmistusprosessia. Laadunvalvonta jakautuu valmistusmateriaalien, itse valmistusprosessin sekä jälkikäsitellyn lopputuotteen laadunvalvontaan. Hyvän AM-prosessin suunnittelun ja toteutuksen sekä laadunvalvonnan tavoite on, että lopputuotteet ovat niille kohdistettujen vaatimusten mukaisia, ja että tuotanto on tehokasta ja kannattavaa.

3D printing is changing the whole manufacturing concept of components and products. The freedom of design in 3D printing opens new ways to produce structures with advanced properties. Additive manufacturing is nowadays utilised in some industrial applications, however, there is a need to develop new materials with high quality properties. New tailored materials and optimised 3D printing techniques will make the utilisation of additive manufacturing possible in many new applications. In this project, the biomimetic multi-scale hierarchical approach was the inspiration for design of materials and structures. In macro to micro-level, the project focused on utilising advanced functional printing technologies in the development of new kinds of ceramic- and cement-based materials with high specific strength. In addition, some organic materials were produced and printed In micro to nano-level, the formation of cementitious materials was studied, and routes for controlling the crystal growth were examined. The experimental part of the project consisted of production of printable paste-like materials, numerous 3D printing trials and crystal growth manipulation experiments. Results of the project showed the controlling of crystal growth in some extent possible in nano and micro-level. The development of paste materials made the printing of structures possible and the strength of the cement samples with large volumetric porosity was at the same level than that of the casted samples. The result indicates that a structurally designed material possesses far higher strength than materials with random porosity and 3D printing proved to be a viable method for the manufacturing of such material. The work will be continued in additive manufacturing platform at VTT.

An industrial-scale thermal modification method for wood has been developed in Finland at VTT together with Finnish industry. The Finnish thermal modification method is based on heating the wood material for a few hours at high temperatures over 180°C under normal pressure while protecting it with water vapour. Thermal modification changes the chemical and physical properties of wood. During thermal modification the colour of wood darkens, the dimensional stability enhances, equilibrium moisture content reduces and the biological durability increases. On the other hand, as a result of thermal modification, the wood becomes more brittle and bending and tension strength decrease in relation to the level of heat-treatment. Thermally modified wood is used in many applications, where enhanced dimensional stability and biological durability are required. Also, the brown colour of the thermally modified wood is experienced as a benefit in furnishing. There are plenty of good experiences of using thermally modified timber in many different applications like exterior cladding, decking, flooring, garden furniture, panelling, kitchen furnishing and the interiors of bathrooms and saunas.