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An experimental and numerical study of thermal profiles of 316 L stainless steel during selective laser melting (SLM) was developed. This study aims to present a novel approach to determine the significance and contribution of thermal numerical modeling enhancement factors of SLM.

Surface and volumetric heat models were proposed to compare the laser interaction with the powder bed and substrate, considering the powder size, absorptance and propagation of the laser energy through the effective depth of the metal layer. The approach consists in evaluating the contribution of the thermal conductivity anisotropic enhancement factors to establish the factors that minimized the error of the predicted results vs the experimental data.

The level of confidence of the carried-out analysis is of 97.8% for the width of the melt pool and of 99.8% for the depth of the melt pool. The enhancement factors of the y and z spatial coordinates influence the most in the predicted melt pool geometry.

Nevertheless, the methodology presented in this study is not limited to 316 L stainless steel and can be applied to any metallic material used for SLM processes.

This study is focused on 316 L stainless steel, which is commonly used in SLM and is considered a durable material for high-temperature, high-corrosion and high-stress situations.

The additive manufacturing (AM) technology is a relatively new technology becoming global. The AM technology may have health benefits when compared to the conventional industrial processes, as the workers avoid extended periods of exposure present in conventional manufacturing.

This study presents a novel approach to determine the significance and contribution of thermal numerical modeling enhancement factors of SLM. It was found that the volumetric heat model and anisotropic enhancement thermal approaches used in the present research, had a good agreement with experimental results.

A key challenge found in additive manufacturing is the difficulty to produce components with replicable microstructure and mechanical performance in distinct orientations. This study aims to investigate the influence of build orientation on the fracture toughness of additively manufactured AlSi10Mg specimens.

The AlSi10Mg specimens were manufactured using the selective laser melting (SLM) technology. The fracture toughness was experimentally determined (under ASTM E399-09) using C(T) specimens manufactured in different orientations. The microstructure of the specimens was examined using metallography to determine the effects of grain orientation on fracture toughness.

The fracture toughness magnitude of manufactured specimens ranged between 36 and 50 MPam, which closely matched conventional bulk material and literature values regarding AlSi10Mg components. The C(T) specimens printed in the T-L orientation yielded the highest fracture toughness. The grain orientation and fracture toughness values confirm the anisotropic nature of SLM parts where the T-L-oriented specimen obtained the highest K_IC value. A clear interaction between the melt pool boundaries and micro-slipping during the loading application was observed.

The novelty of this paper consists in elucidating the relationship between grain orientation and fracture toughness of additively manufactured AlSi10Mg specimens because of the anisotropy generated by the different melting pool boundaries and orientations in SLM. The findings show that melt pool boundaries can behave as easier pathways for cracks to propagate and subsequently reduce the fracture toughness of specimens with cracks perpendicular to the build direction.

The academic literature and research lines exploring the effect of quality improvement methods on environmental performance still remain in early stages. The purpose of this paper is therefore to investigate, through a systematic review of the existing academic literature, the environmental (green) impact of using quality and operations improvement methods such as Lean, Six Sigma and Lean Six Sigma. This includes the impact on energy saving and the usage of natural resources.

This study follows a systematic literature review approach through which it analyses research papers published in top 16 operations and quality management journals. No specific time frame was established, but a set of keywords were used to short-list the articles. A sample of 70 articles was finally short-listed and analysed to provide a discussion on environmental concerns related to Lean, Six Sigma and Lean Six Sigma.

The comprehensive review of short-listed articles indicates that both Lean and Six Sigma can be considered effective methods to support the conservation of resources, combat global warming and saving energy. Various scholars provide evidence of this, and as such, organisations should not only consider these methods to manage quality and improve operational performance but also meet environmental regulations. A set of research questions that demands further investigation has also been proposed based on the findings of this research.

This study is limited to a sample of 70 articles collected from top 16 operations and quality management journals. The search of journals is also limited to a set of key words (“Lean”, “Green”, “Six Sigma”, “environment”, “sustainable” and “sustainability”) used to short-list the sample size.

The study shows that organisations can consider the adoption of Lean, Six Sigma and Lean Six Sigma to meet environmental regulations, save costs and also meet quality management standards. This will contribute in helping organisations to formulate more effective and inclusive strategies which do not only consider the quality and operational dimensions but also the environmental dimension.

Literature exploring the environmental/green impact of quality management methods commonly used in industry is limited. There is also a lack of studies aiming to investigate the green impact of Lean and Six Sigma in top operations and quality management journals. The study focusing on investigating the green impact of Lean, Six Sigma and Lean Six Sigma methods altogether is also a research first of its kind.

Equipment performance helps the manufacturing sector achieve operational and financial improvements despite process variations. However, the literature lacks a clear index or metric to quantify the monetary advantages of enhanced equipment performance. Thus, the paper presents two innovative monetary performance measures to estimate the financial advantages of enhancing equipment performance by isolating the effect of manufacturing fluctuations such as product mix price, direct and indirect characteristics, and cost changes.

The research provides two measures, ISB (Improvement Saving Benefits) and IEB (Improvement Earning Benefits), to assess equipment performance improvements. The effectiveness of the metrics is validated through a three stages approach, namely (1) experts' binary opinion, (2) sample, and (3) actual cases. The relevant data may be collected through accounting systems, purpose-built software, or electronic spreadsheets.

The findings suggest that both measures provide an effective cost–benefit analysis of equipment performance enhancement. The measure ISB indicates savings from performance increases when equipment capacity is greater than product demand. IEB is utilised when equipment capacity is less than product demand. Both measurements may replace the unitary cost variation, which is subject to manufacturing changes.

Manufacturing businesses may utilise the ISB and IEB metrics to conduct a systematic analysis of equipment performance and to appreciate the financial savings perspective in order to emphasise profitability in the short and long term.

The study introduces two novel financial equipment performance improvement indicators that distinguish the effects of manufacturing variations. Manufacturing variations cause cost advantages from operational improvements to be misrepresented. There is currently no approach for manufacturing organisations to calculate the financial advantages of enhancing equipment performance while isolating production irregularities.

This paper aims to explore synergies between lean production (LP) and six sigma principles to propose a lean six sigma (LSS) framework for continuous and incremental improvement in the oil and gas sector. The Three-dimensional LSS framework seeks to provide various combinations about the integration between LP principles, DMAIC (define–measure–analyse–improve–control) cycle and plan-do-check-act (PDCA) cycle to support operations management needs.

The research method is composed of two main steps: diagnosis of current problems and proposition of a conceptual framework that qualitatively integrates synergistic aspects of LP and six sigma and analysis of the application of the construct through semi-structured interviews with leaders from oil and gas companies to assess and validate the proposed framework.

As a result, a conceptual framework of LSS is developed contemplating the integration of LP and six sigma and providing a systemic and holistic approach to problem-solving through continuous and incremental improvement in the oil and gas sector.

This research is different from previous studies because it integrates LP principles, DMAIC and PDCA cycles into a unique framework that fulfils a specific need of oil and gas sector. It presents a customized LSS framework that guides wastes and cost reduction while enhancing quality and reducing process variability to elevate efficiency in operations management of this sector. This is an original research that presents new and original scientific findings.

The purpose of this paper is to explore the relationship between knowledge management and creation of intellectual property within the context of small and medium size manufacturing enterprises.

A hypothesis was formulated and tested using structural equation modelling. Data were collected through an instrument that was developed based on key constructs adapted from the literature and that was first validated using Confirmatory Factor Analysis. A Cronbach’s alpha test was also conducted and the Composite Reliability Index was calculated to ensure reliability of the theoretical model. The instrument was distributed among manufacturing small and medium enterprises (SMEs) in the Aguascalientes region of Mexico, from were 125 valid responses were obtained.

In general, the results indicate that knowledge management has positive effects on the creation of intellectual property in manufacturing SMEs. This suggests that SMEs can create more intellectual property if they dedicate more efforts to the management of knowledge.

The implication of this research and its findings may inform the strategies formulated by policy makers, and the managerial practices that manufacturing SMEs can adopt to protect their knowledge.

Evidence suggests that studies focused on investigating the relationship between knowledge and intellectual property are limited. This paper provides a refined understanding of the relationship between knowledge management and intellectual property creation.

The purpose of this paper is to explore how rising technologies from Industry 4.0 can be integrated with circular economy (CE) practices to establish a business model that reuses and recycles wasted material such as scrap metal or e-waste.

The qualitative research method was deployed in three stages. Stage 1 was a literature review of concepts, successful factors and barriers related to the transition towards a CE along with sustainable supply chain management, smart production systems and additive manufacturing (AM). Stage 2 comprised a conceptual framework to integrate and evaluate the synergistic potential among these concepts. Finally, stage 3 validated the proposed model by collecting rich qualitative data based on semi-structured interviews with managers, researchers and professors of operations management to gather insightful and relevant information.

The outcome of the study is the recommendation of a circular model to reuse scrap electronic devices, integrating web technologies, reverse logistics and AM to support CE practices. Results suggest a positive influence from improving business sustainability by reinserting waste into the supply chain to manufacture products on demand.

The impact of reusing wasted materials to manufacture new products is relevant to minimising resource consumption and negative environmental impacts. Furthermore, it avoids hazardous materials ending up in landfills or in the oceans, seriously threatening life in ecosystems. In addition, reuse of wasted material enables the development of local business networks that generate jobs and improve economic performance.

First, the impact of reusing materials to manufacture new products minimises resource consumption and negative environmental impacts. The circular model also encourages keeping hazardous materials that seriously threaten life in ecosystems out of landfills and oceans. For this study, it was found that most urban waste is plastic and cast iron, leaving room for improvement in increasing recycling of scrap metal and similar materials. Second, the circular business model promotes a culture of reusing and recycling and motivates the development of collection and processing techniques for urban waste through the use of three-dimensional (3D) printing technologies and Industry 4.0. In this way, the involved stakeholders are focused on the technical parts of recycling and can be better dedicated to research, development and innovation because many of the processes will be automated.

The purpose of this study was to explore how Industry 4.0 technologies are integrated with CE practices. This allows for the proposal of a circular business model for recycling waste and delivering new products, significantly reducing resource consumption and optimising natural resources. In a first stage, the circular business model can be used to recycle electronic scrap, with the proposed integration of web technologies, reverse logistics and AM as a technological platform to support the model. These have several environmental, sociotechnical and economic implications for society.

The sociotechnical aspects are directly impacted by the circular smart production system (CSPS) management model, since it creates a new culture of reuse and recycling techniques for urban waste using 3D printing technologies, as well as Industry 4.0 concepts to increase production on demand and automate manufacturing processes. The tendency of the CSPS model is to contribute to deployment CE in the manufacture of new products or parts with AM approaches, generating a new path of supply and demand for society.

The academic literature and motivational theory recognise the positive role of motivation on organisational performance and considers personal development as a key motivational factor. In practice, most organisations employ a personal development review (PDR) process to drive and plan the development of their staff. The purpose of this paper is to investigate the interrelation and impact of the PDR process, and its elements, on staff motivation.

The study is based on a case study research approach carried out in two large manufacturing-engineering departments of a world-class manufacturing organisation. A survey questionnaire was designed, validated and distributed to the engineering staff and its results were analysed using descriptive statistics.

The study's results indicate that in most of the cases, a PDR process does not by itself motivate staff. But it argues that a poorly designed and conducted PDR process may make motivation, through personal development, difficult to achieve.

This paper provides manufacturing managers with an opportunity to understand whether a common business process (i.e. PDR), and the elements that comprise it, can be employed as a method to aid in the motivation of their staff.

This research expands the current knowledge on motivational and manufacturing management theory by performing an initial and exploratory study that establishes the impact of the PDR process on staff motivation. It is among the very first investigations that correlate the PDR process and motivation, especially in the manufacturing industry.