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The purpose of this paper is to investigate the combination of selective laser melting (SLM) and 5-axis CNC milling to produce parts from titanium powder. The aim is to achieve a more resource-efficient manufacturing process by reducing material wastage and machining time, while adhering to quality requirements.

A benchmark titanium aerospace component is manufactured with two different approaches using subtractive and additive manufacturing technologies. The first component is produced from a solid billet using only 5-axis CNC milling. The second component is grown from powder using SLM to produce a net-shaped part of which the final shape and part accuracy are achieved through 5-axis CNC milling. The potential saving of material and machining time of the process combination is evaluated by comparing it to the conventional purely CNC approach. The form accuracy, surface finish, mechanical properties and tool wear for the two processes are also compared.

The results show that the process combination can be used to produce Ti components that adhere to aerospace standards. With the process combination, a material saving of 87 per cent was achieved along with a reduction of 21 per cent in machining time. Further improvements are possible using optimized SLM build and machining strategies.

This paper presents the results of a resource efficiency assessment on the combination of SLM and 5-axis CNC milling for the titanium alloy, Ti6Al4V. It is expected that this process combination can make a significant contribution towards reducing material wastage and machining time for aerospace applications.

Selective laser melting (SLM) is a process that produces near net shape parts from metallic powders. A concern with SLM-produced metals is the achievable materials performance with respect to mechanical properties. Particularly, three important aspects strongly affect the mechanical properties of the material: internal stresses resulting from steep temperature gradients and high cooling rates, the resulting microstructure and the occurrence of pores and flaws.

This paper presents SLM-produced maraging steel 300 (18Ni-300), an iron-nickel steel alloy often used in applications where high fracture toughness and strength are required. The steel’s achievable tensile, crack growth and hardness properties and the manner in which these compare to the wrought counterpart are reported. In addition, this paper investigates the porosity distribution and achievable density, residual stress levels and post-processing procedures using heat-treatments.

It is found that tensile properties, hardness and microstructure compare well to its wrought counterpart. Fatigue growth rates are also comparable, though they are influenced by residual stresses and microstructure.

The investigation into the mechanical performance addresses two issues: the achievable mechanical properties and the understanding of the link between the manufacturing process and the achievable material performance.

In a previous Rapid Prototyping Journal paper, the authors reviewed the first decade of rapid prototyping (RP) use within the Republic of South Africa (RSA). The paper analysed its strengths, weaknesses, opportunities and threats, and proposed a “road map” for future development. Much has happened in the intervening years since that article was published and this paper seeks to update readers on the current situation in RSA. In particular, it reports the extensive development of research in the field of RP and additive manufacturing (AM).

The paper uses a literature review approach combined with reflective analysis to distill the most important developments within the RP community in RSA since 2004. These are compared to the previous road map to ascertain if there are any required actions that have been overlooked or any additional lessons that have been learnt.

The paper shows that there has been good progress against the previous road map and that current plans should remain in place with the addition of a greater educational dimension.

This paper provides readers with an overview of important RP/AM developments in the RSA. The analysis from this paper will aid RSA academics, industrialists and government agencies to assess their performance and to plan for their future roles within the RP community.

As with the previous paper, this paper provides a useful model for other countries to follow since it demonstrates both good practice but also the need to learn from past experience.

The main aim of the paper is the application of the selective laser sintering (SLS) method for fabrication of hydrodynamic torque converter (HTC) impellers.

Establishing of assumptions for the impeller design process based on the HTC characteristics analysis, creation of the virtual solid model of HTC impellers, fabrication of HTC impellers by using the SLS method, investigation of the performance of HTC with fabricated impellers by using a test rig.

The test results show that the SLS method can be successfully used for the fabrication of HTC impellers with 3D and flat blades.

The method application is limited to small diameters of HTC impellers depending on working area dimensions of SLS machine.

The method can decrease the time and cost of fabrication of HTC impellers by using the SLS method.

The application of the SLS method for fabrication of HTC impellers with 3D and flat blades.

This paper surveys the current state and capabilities of three dimensional printing (3DP). A comprehensive review of 3D Printing applications is presented. The scope of the applications includes design, manufacturing, the medical field and architecture.

A large variety of manufacturing applications such as rapid pattern making and rapid tooling using the 3DP process directly or as core technology, as well as further implications in design and engineering analysis, medicine, and architecture are presented and evaluated.

Some research issues are also discussed. An attempt, based on the state of the art, to show weaknesses and opportunities, and to draw conclusions about the future of this important process rounds up this paper.

The scope of this research survey is limited to evaluation and comparison of processes that may be characterised as 3D printing technologies.

The study is very useful as a basis for matching evaluated 3D printing machine and process capabilities to user requirements, and forms a framework on which future comparative studies can build.

A comprehensive overview of the capabilities of 3DP processes is presented and evaluated. It shows the application of 3D printing beyond concept modelling. The paper is valuable for researchers as well as individuals, who require adequate and relevant comparative information during decision making.

This study has demonstrated how technology may contribute to integrated care solutions by comparing conventional ward telemetry (WT) to a wearable ECG monitor (S-Patch) to detect atrial fibrillation (AF) in patients with stroke.

51 patients admitted for stroke workup were recruited across two major tertiary centres to compare WT monitoring for two days versus S-Patch for four days in the detection of AF. The efficacy to detect AF using both technologies was assessed via data extractions and medical officer review. A matrix was used to measure nursing/patient satisfaction and setup/resource times were assessed.

Patients (84–94%) and nursing staff (75–95%) preferred the S-Patch wearable technology. Non-parametric tests indicated significant time saving for removal of S-Patch versus WT [2.2 min vs 5.1 min (p = 0.00)]. Efficacy of S-Patch to detect AF following medical officer review was greater than WT, with seven patients identified with AF by S-Patch versus one using WT. The S-patch had a false positive rate of 78%.

The S-Patch is sensitive in the detection of AF; however, it showed a high false-positive rate with automated reporting. This study has provided insight into the details of delivery of integrated healthcare using wearable technology.

The technology and partnership were the first-in-kind in Australia. The S-Patch had a higher detection rate of AF compared to WT which allows patients to be anti-coagulated appropriately for the prevention of further stroke. The results of this study will be ideally placed to inform future policy in integrated healthcare using new technologies.

To review the state-of-the-art in smart remanufacturing, highlighting key elements of an Industry 4.0 (I4.0) future that supports circular economy (CE) principles and offer a conceptual framework and research agenda to accelerate digitalisation in this sector.

The Scopus, Web of Science and ScienceDirect databases and search terms “Industry 4.0”, “Internet of things”, “Smart manufacturing” and “Remanufacturing” were used to identify and select publications that had evidence of a relationship between those keywords. The 329 selected papers were reviewed with respect to the triple bottom line (economic, social and environmental). The study benefited from advanced text quantitative processing using NVivo software and a complete manual qualitative assessment.

Changes in product ownership models will affect the remanufacturing industry, with the growth of product-service-systems seen as an opportunity to re-circulate resources and create value. This is being supported by changes in society, user expectations and workforce attributes. Key to the success of remanufacturing in an I4.0 future is the uptake of existing and emerging digital technologies to shorten and strengthen links between product manufacturers, users and remanufacturers.

Remanufacturing is recognised as a key CE strategy, which in turn is an important research area for development in our society. This article is the first to study “smart remanufacturing” for the CE. Its uniqueness lies in its focus on the remanufacturing industry and the sustainable application of I4.0 enablers. The findings are used to create a framework that links to the research agenda needed to realise smart remanufacturing.