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Mechanical Engineering. 2009;131(01):22-27. doi:10.1115/1.2009-JAN-1.
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This review focuses on the fact that there are many ways to be green, and American manufacturers are trying them all. From reducing energy use and recycling water to implementing ISO 14001 sustainability programs and reusing packaging, US factories are embracing a more environmentally sensitive manufacturing ethos as fast as they can. There are many ways to be green. Ratcheting down energy use, for example, automatically reduces a plant’s carbon footprint, because either it burns less natural gas or it buys less electricity from a power plant that burns coal or gas. Companies around the nation have also turned their Six Sigma, lean manufacturing, and other tools on solid waste. If a material does not add value to a product, they eliminate it. Many work with vendors to reduce packaging. The less packaging, the less energy is used in a product. Capital projects are even harder to push through, yet they are necessary for further gains once companies have plucked waste reduction’s low-hanging fruit.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(01):30-35. doi:10.1115/1.2009-JAN-2.
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This paper explores the increase in micromanufacturing in diverse Swiss industries. Switzerland Trade and Investment Promotion, in collaboration with the promotional bureaus of Geneva and other cantons, arranged a tour through several of the country’s micromachining businesses and laboratories. A tour of Swiss precision manufacturing included visits to institutions engaged in research and development of micromachining. The technology they are developing into new fields is grounded in the watch business. Oerlikon Space AG in Zurich makes a variety of high-tech products for space programs, including the payload fairings for vehicles that carry cargo into space. In order to qualify as Swiss made, the major parts of a watch must be assembled in Switzerland, and at least half the tiny parts of the movement have to be made in the country. To do that, the Swiss need an industry that can make things that small, and do it reliably.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(01):36-40. doi:10.1115/1.2009-JAN-3.
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This article highlights three-dimensional printing as a rapid pro to typing process that builds objects by depositing a material such as thermoset resin in layers one on the other. Desktop 3D printers are now relatively inexpensive. Traditionally, printed models have been dipped in an epoxy resin. FigurePrints uses an automated system from xlaForm that allows parts to be infused in bulk in a heating machine. This method cuts processing time and labor costs, but is still time-consuming and allows processing only in batches. Wohlers is also watching Shapeways of Eindhoven in the Netherlands, which has married 3D printing with the crowdsourcing model now being blazed on the Internet. This model asks Internet users to design or create products and then rank the results. At Shapeways, which is actually a business incubator sponsored by Koninklijke Philips Electronics NV, consumers upload their own 3D models, which are then printed and shipped. Users can also purchase models.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2009;131(01):41-45. doi:10.1115/1.2009-JAN-4.
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This article reviews the mechanical design and a set of practical guidelines for design engineers. Engineers have plenty of technology for controlling friction and wear, including naturally lubricious materials, high-performance lubricants, and rolling element bearings. But where friction is concerned, good mechanical design starts with guidelines. Friction changes with time, reflecting sliding-induced changes to the interface. The traditional single static and single dynamic coefficients of friction are misleading because they do not reflect fluctuations and transitions in friction. The friction coefficient, static or dynamic, has no single, unique value for a given material pair, but rather is a characteristic of those materials when rubbed together under specific conditions. Friction and wear are not material properties; they are system properties. So many test protocols, such as thrust washer tests, will give one result, but actual systems will have different results.

Topics: Friction , Wear , Stress
Commentary by Dr. Valentin Fuster

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