Increasing attention has recently been drawn to the energy consumption of the manufacturing process. Manufacturers are facing challenges from society of reducing emissions and operating more efficiently because of rising raw material prices and energy costs. Manufacturers are trying to balance among the total energy, economic and environmental targets simultaneously, a strategy that can be self-conflicting at times. This paper focuses on the objective optimizations of a plantlevel energy supply system, and describes how a multiobjective optimization strategy can be effectively formulated for making the best use of energy delivered to the manufacturing process. An example from an automotive assembly manufacturer is described.

Increasingly strict fuel efficiency standards have driven the aerospace and automotive industries to improve the fuel economy of their fleets. A key method for feasibly improving the fuel economy is by decreasing the weight, which requires the introduction of materials with high strength to weight ratios into airplane and vehicle designs. Many of these materials are not as formable or machinable as conventional low carbon steels, making production difficult when using traditional forming and machining strategies and capital. Electrical augmentation offers a potential solution to this dilemma through enhancing process capabilities and allowing for continued use of existing equipment. The use of electricity to aid in deformation of metallic materials is termed as electrically assisted manufacturing (EAM). The direct effect of electricity on the deformation of metallic materials is termed as electroplastic effect. This paper presents a summary of the current state-of-the-art in using electric current to augment existing manufacturing processes for processing of higher-strength materials. Advantages of this process include flow stress and forming force reduction, increased formability, decreased elastic recovery, fracture mode transformation from brittle to ductile, decreased overall process energy, and decreased cutting forces in machining. There is currently a lack of agreement as to the underlying mechanisms of the electroplastic effect. Therefore, this paper presents the four main existing theories and the experimental understanding of these theories, along with modeling approaches for understanding and predicting the electroplastic effect.

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Dramatic advancements and adoption of computing capabilities, communication technologies, and advanced, pervasive sensing have impacted every aspect of modern manufacturing. Furthermore, as society explores the Fourth Industrial Revolution characterized by access to and leveraging of knowledge in the manufacturing enterprise, the very character of manufacturing is rapidly evolving, with new, more complex processes, and radically, new products appearing in both the industries and academe. As for traditional manufacturing processes, they are also undergoing transformations in the sense that they face ever-increasing requirements in terms of quality, reliability, and productivity, needs that are being addressed in the knowledge domain. Finally, across all manufacturing we see the need to understand and control interactions between various stages of any given process, as well as interactions between multiple products produced in a manufacturing system. All these factors have motivated tremendous advancements in methodologies and applications of control theory in all aspects of manufacturing: at process and equipment level, manufacturing systems level, and operations level. Motivated by these factors, the purpose of this paper is to give a high-level overview of latest progress in process and operations control in modern manufacturing. Such a review of relevant work at various scales of manufacturing is aimed not only to offer interested readers information about state-of-the art in control methods and applications in manufacturing, but also to give researchers and practitioners a vision about where the direction of future research may be, especially in light of opportunities that lay as one concurrently looks at the process, system and operation levels of manufacturing.

Tool condition monitoring (TCM) is an important aspect of condition based maintenance (CBM) in all manufacturing processes. Recent work on TCM has generated significant successes for a variety of cutting operations. In particular, lower cost and on-board sensors in conjunction with enhanced signal processing capabilities and improved networking has permitted significant enhancements to TCM capabilities. This paper presents an overview of TCM for drilling, turning, milling, and grinding. The focus of this paper is on the hardware and algorithms that have demonstrated success in TCM for these processes. While a variety of initial successes are reported, significantly more research is possible to extend the capabilities of TCM for the reported cutting processes as well as for many other manufacturing processes. Furthermore, no single unifying approach has been identified for TCM. Such an approach will enable the rapid expansion of TCM into other processes and a tighter integration of TCM into CBM for a wide variety of manufacturing processes and production systems.

Currently, the automotive and aircraft industries are considering increasing the use of magnesium within their products due to its favorable strength-to-weight characteristics. However, the implementation of this material is limited as a result of its formability. Partially addressing this issue, previous research has shown that electrically-assisted forming (EAF) improves the tensile formability of magnesium sheet metal. While these results are highly beneficial toward fabricating the skin of the vehicle, a technique for allowing the use of magnesium alloys in the production of the structural/mechanical components is also desirable. Given the influence that FAF has already exhibited on tensile deformation, the research herein focuses on incorporating this technique within compressive operations. The potential benefit of using FAF on compressive processes has been demonstrated in related research where other ntaterials, such as titanium artd aluminum, have shown improved compressive behavior. Therefore, this research endeavors to amalgamate these findings to Mg AZ31B-0, which is traditionally hard to forge. As such, to demonstrate the effects of FAF on this alloy, two series of tests were petformed. First, the sensitivity of the alloy to the FAF process was determined by varying the current density and platen speed during an upsetting process (flat dies). Then, the ability to utilize impression (shaped) dies was examined. Through this study, it was shown for the first time that the FAF process increases the forgeability of this magnesium alloy through improvements such as decreased machine force requirements and increased achievable deformation. Additionally, the ability to form the desired final specimen geometry was achieved. Furthermore, this work also showed that this alloy is sensitive to any deformation rate changes when utilizing the FAF process. Last, a threshold current density was noted for this material where significant forgeability improvements could be realized once exceeded.

The process of friction stir welding involves high tool forces and requires robust machinery; the forces involved make tool wear a predominant problem. As a result, many alternatives have been proposed in decreasing tool forces such as laser assisted friction stir welding and ultra-sound assisted friction stir welding. However, these alternatives are not commercially successful on a large scale due to scalability and capital/maintenance costs. In an attempt to reduce forces in a cost-feasible manner, electrically-assisted friction stir welding (EAFSW) is studied in this work. EAFSW is a result of applying the concept of electrically-assisted manufacturing (i.e., passing high direct electrical current through a workpiece during processing) to the conventional friction stir welding process. The concept of EAFSW is a relatively new adaptation of conventional frictional stir welding, which is well established. The expected benefits are reduction in the feed force and torque, which allow for improved processing productivity as well as the possibility for deeper penetration of the weld.