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Additive Manufacturing of cellular lattice structures offers opportunities to fine-tune the mechanical response by altering geometric variables. It is known that heat treatment cycles provide an effective way of altering mechanical properties while relieving residual stress. By exploiting the combined influence of these two variables, this study demonstrates the possibility of optimising energy absorption in AlSi10Mg honeycomb lattice structures, manufactured using selective laser melting. This finding indicates that heat treatment and powder quality have a significant influence on the mechanical response of the honeycomb. Additionally, this highlights the opportunity to establish an energy absorption diagram, via mapping the relative performance of variable lattice geometries and heat treatment cycles. At the same time, the consistency of powder quality can be tightly controlled.

Porous structures fabricated using additive manufacturing demonstrate significant advantages due to their mechanical properties and light weight. However, their manufacture using selective laser melting still requires considerable research. This study investigated the mechanical properties and the failure modes of Ti–6Al–4V-built Schwarz primitive structures. Samples with five different porosities, ranging from 60 to 85%, were designed and fabricated; all samples had a length of 20 mm and consisted of 2.5-mm porous units. Compression tests were conducted to study their mechanical properties. The results show that their elastic modulus ranged from 1239.63 ± 23.69 to 3453.20 ± 105.95 MPa, and their ultimate strength ranged between 44.82 ± 0.22 and 266.31 ± 0.73 MPa. A camera used to record the failure processes revealed that Ti–6Al–4V Schwarz primitive structures exhibit brittle behaviour. Two failure modes were observed; diagonal shear was found in the 60–80% porosity samples, while unit brittle fracturing was observed in the 85% samples. This study contributes new knowledge about the design of Schwarz primitive structures and provides guidelines for choosing the appropriate porosity to meet different application requirements.

Aluminium is the third most abundant material in the Earth’s crust and, along with its alloys, is essential in many engineering sectors, including aerospace, automotive, defence, marine, construction, and medicine, owing to its high damage tolerance, fatigue resistance, conductivity, corrosion resistance, and low density. Despite this, some mechanical properties of Aluminium do not yet satisfy increasing industrial demands. Reinforcing aluminium alloys with other elements is considered as a means of providing additional strength. This study aims to investigate the effect of milling speed and time on graphene-reinforced aluminium alloy powder, intended for use in selective laser melting (SLM), prepared using high-energy ball milling (HEBM). The experimental study indicates that using a slow milling speed (100 rpm) for up to 2 h does not affect the shape of the powder substantially, and the graphene nanoparticles (GNPs) do not adhere to the powder surface in a metal matrix composite (MMC). However, a faster milling speed (250 rpm) flattens and crumbles the powder, and adheres the graphene sheets to the alloying powder, due to the higher impact energy produced by centrifugal and Coriolis forces.

Additive Manufacturing technologies are becoming increasingly prevalent in commercial practice, and as a result more attention is gradually being devoted to their implications for supply chain management. One pertinent topic for these technologies that remains largely unexplored is that of Supply Chain Risk Management. This paper serves to provide an initial contribution in the form of a conceptual framework that may serve to underpin future research.

Sustainability in all its guises is important for the long term continuance of manufacturing. The ideas of local sustainability and resilience have become increasing popular topics for study. The drive for economic resilience is causing governments to look at regional strategies to improve economic sustainability and resilience. A recent example of this is the establishment of a Cardiff Capital Region (CCR) in Wales. This exploratory study takes an initial look at the resilience of manufacturing in the CCR vis-à-vis economic resilience using the FAME dataset and QuiScore measure. Results indicate that on the whole manufacturing looks broadly healthy. However, some potential areas of concern were identified, many of the biggest and healthiest companies are not headquartered in the CCR, whereas 98 % of the weakest companies are, and there are inter and intra sectorial differences. The study also suggests that measures such as QuiScore should perhaps not be used in isolation as its methodology is unknown and a large number of companies do not have QuiScores.

This paper outlines how the economic and environmental sustainability of SMEs in particular can be improved by ensuring that their manufactured product’s Sustainable Life Cycle Costs (SLCC) are minimised. It advocates that this may be achieved through the correct use of Manufacturing Management Informatics (MMI), initially to ensure the correct selection of engineering materials and subsequently for product-manufacturing system—process—recycling design. By adopting such an approach, which in essence employs Flexible Integrated Technology (FIT) it is proposed that a company can not only achieve a significant reduction in their operational costs but also establish a lasting improvement in their productivity, competitive position, economic and environmental sustainability and overall profitability. Within the paper, a proposed methodology for achieving minimum sustainable life cycle costs is outlined. This emphasises the requirement for and correct use of manufacturing management informatics in product, manufacturing system, process and recycling design, to ensure efficient low cost sustainable manufacture. A case study is included, which assesses the effectiveness of the approach proposed by utilising a comparative before and after example in a construction industry SME. This indicates how the proposed methodology can be implemented in an incremental and concurrent manner via the use of existing concepts, strategies, innovative thinking and suitable manufacturing management informatics software.

This paper presents the results from a survey of emerging and micro SMEs, along with entrepreneurs, creative practitioners, and the new group of ‘makers’, who are beginning to adopt (or consider adopting) the newer entry-level emergent technologies such as 3D printing. A number of key findings are discussed: including, the prevalence of ‘self-taught’ users of these technologies; major business activity in the creative industry space; the importance of shared equipment usage by micro organisations in comparison to small companies using external bureau services. Unsurprisingly cost is still cited as a factor for poor uptake of emergent technologies, closely followed by a low awareness of 3D printing and its capabilities, and 3D printing supply chains. Skill levels reported by the participants for each technology highlighted that 3D printing had the most pro-users, which may highlight the increased access to such technologies for micro enterprises, typically reserved for incumbent organisations.

Additive Manufacturing (AM) is gaining increasing interest as a sustainable manufacturing technology. One important aspect of AM is the opportunities it presents for customization by increasing involvement of customer in the design and manufacturing process. This paper presents a review of literature examining proposed future scenarios for AM implementation, with particular interest in the way customers are engaged in the process, and the effect that this might have on the future of AM supply chains. 27 distinct scenarios for future AM implementations were identified, with Engineer-to-Order and Make-to-Order proving most popular approaches, alongside a trend towards localized production. Although structured methods are available, a “genius” approach was found to have been employed in developing the majority of the scenarios evaluated.

Unlike subtractive manufacturing processes, by their own nature additive technologies offer the potential to reduce both raw material consumption and production waste. The positive impact of Additive Manufacturing on sustainability is more evident for those mass consumption products that are characterized by a short lifecycle. Nevertheless, in order to take full advantage of these technologies and let them achieve their full potential, a great change is needed in the behaviour and attitude of consumers. Compromises may be necessary to accommodate technological limitations, and customers may need to prioritize between functional and aesthetic product characteristics. The positive impact of additive manufacturing on sustainability is more evident for those mass consumption products that are characterized by a short lifecycle. The material flow and sustainability of 3D printing are described in this paper for the manufacturing of mobile case covers, and compared to those of mass production injection moulding.

The application of an integrated eco-design decision making tool is presented as a case study considering the design of an office chair base. This study brings together the analysis of factors relating to manufacturing processes, product usage and end-of-life strategy to demonstrate the operation of an eco-design case-based reasoning tool. This is shown to meet the requirement of the data storage, retrieval and re-use. A framework is provided to facilitate the application of sustainability criteria in the early design phase in a context with which designers are familiar. Such consideration can be made more understandable and relevant as more information is added. This makes all aspects of the process more rewarding for the participants and increases considerations of sustainability.

Sustainability within manufacturing is an increasingly important topic globally. One course of action being explored is to produce more parts ‘right first time’ so supporting an increasingly sustainable manufacturing process. This paper explores the Renishaw “productive process pyramid” and considers how it can be integrated into the ALM process. The pyramid is currently used to identify how layers of control can systematically remove variation from conventional machining processes. This application is focussed to consider how the variables that occur within the ALM manufacturing process can impact on the quality of the parts mechanically and geometrically. This approach can then inform the process foundation and process setting stages and enhance levels of in-process control.

This paper focuses on processing cross-domain document repositories, which is challenged by the word ambiguity and the fact that monosemic words are more domain-oriented than polysemic ones. The paper describes a semantically enhanced text normalization algorithm (SETS) aimed at improving document clustering and investigates the performance of the sk-means clustering algorithm across domains by comparing the cluster coherence produced with semantic-based and traditional (TF-IDF-based) document representations. The evaluation is conducted on 20 generic sub-domains of a thousand documents each randomly selected from the Reuters21578 corpus. The experimental results demonstrate improved coherence of the clusters produced by SETS compared to the text normalization obtained with the Porter stemmer. In addition, semantic-based text normalization is shown to be resistant to noise, which is often introduced in the index aggregation stage.