Understanding surface roughness generation in machining is critical to estimate the final quality of the part, optimize cutting conditions, reduce costs and improve manufacturing sustainability in industry. This work presents a review of the factors that affect surface roughness generation in machining (turning/milling) processes. Up to twenty-five different factors were identified, which were classified as setup factors (cutting tool, machine tool/fixturing and workpiece factors), operational factors (cutting and process parameters) and processing factors, which are related to the resulting cutting processes, such as built-up edge, chatter or tool wear. The importance of understanding these factors to improve machining sustainability is highlighted through three case studies, ranging from a simple change in the cutting insert to a more complex case where a controlled surface roughness leads to the elimination of a grinding stage. A case study illustrating the potential benefit of MQL in the sustainability of the machining process is also reported from the mold manufacturing industry. In all of the cases, the improvement in sustainability in terms of the reduction in kg of CO₂ equivalent is notable, especially when grinding operations are reduced or eliminated from the manufacturing process. This paper can be of interest to practitioners in finishing operations at milling and turning operations that want to increase machining sustainability through a deep understanding of surface roughness generation.

Manual tasks play an important role in social sustainable manufacturing enterprises. Commonly, manual operations are used for low volume productions, but are not limited to. Operational models in manufacturing systems based on “x-to-order” paradigms (e.g. assembly-to-order) may require manual operations to speed-up the ramp-up time of new product configuration assemblies. The implications of manual operations in any production line may imply that any manufacturing or assembly process become more susceptible to human errors and therefore translate into delays, defects and/or poor product quality. In this scenario, virtual and augmented realities can offer significant advantages to support the human operator in manual operations. This research work presents the development of a mixed (virtual and augmented) reality assistance system that permits real-time support in manual operations. A review of mixed reality techniques and technologies was conducted, where it was determined to use a projection mapping solution for the proposed assistance system. According to the specific requirements of the demonstration environment, hardware and software components were chosen. The developed mixed reality assistance system was able to guide any user without any prior knowledge through the successful completion of the specific assembly task

Despite the copious amount of research on the design and operation of micromixers, there are few works regarding manufacture technology aimed at implementation beyond academic environments. This work evaluates the viability of xurography as a rapid fabrication tool for the development of ultra-low cost microfluidic technology for extreme Point-of-Care (POC) micromixing devices. By eschewing photolithographic processes and the bulkiness of pumping and enclosure systems for rapid fabrication and passively driven operation, xurography is introduced as a manufacturing alternative for asymmetric split and recombine (ASAR) micromixers. A T-micromixer design was used as a reference to assess the effects of different cutting conditions and materials on the geometric features of the resulting microdevices. Inspection by stereographic and confocal microscopy showed that it is possible to manufacture devices with less than 8% absolute dimensional error. Implementation of the manufacturing methodology in modified circular shape- based SAR microdevices (balanced and unbalanced configurations) showed that, despite the precision limitations of the xurographic process, it is possible to implement this methodology to produce functional micromixing devices. Mixing efficiency was evaluated numerically and experimentally at the outlet of the microdevices with performances up to 40%. Overall, the assessment encourages further research of xurography for the development of POC micromixers.