Laser metal deposition of steel components using machining waste as build material
Gas atomised metal powders are generally used in laser cladding. However, costly new powders prompt the use of machining swarf as an alternative build material. This paper reports on this investigation and establishes its feasibility.
Multiple-layer laser deposition of steel components using gas- and water-atomised powders: The differences and the mechanisms leading to them
Functionally-graded or composite components have been recognised as having immense potential for many industries. The flexibility of direct metal deposition (DMD) has the potential to expand this to microstructurally graded components, but accurate control of the process is a problem. In this work, the effects of using different powder morphologies as a control mechanism for microstructure and other material properties are investigated experimentally. For the first time, comparison of the characteristics of two different gas-atomised (GA) and water-atomised (WA) materials is undertaken in order to evaluate the significance of the different DMD characteristics originating from the difference in atomisation method. 316L and H13 materials and a 1.2 kW CO2 DMD system are used. Three primary factors for the differences are identified: increased vaporisation of the powder, a hotter melt pool and less powerful outward Marangoni flow when using water-atomised powder. The reasons for these, the influence they have on process characteristics and final material properties, and the circumstances under which they occur are discussed. (c) 2005 Elsevier B.V All rights reserved.
Warm Hands in Cold Age – On the Need of a New World Order of Care
The world is aging as fertility and mortality are both decreasing. This article focuses on practical care work for the elderly. Such work is done primarily by women even though a larger portion than previously is paid rather than unpaid. All over the world, most elderly care work is organized within the family, most often unpaid. Men receive more care from partners than women, while women receive more care from female relatives. When care work is paid, the payment is generally low. A comparison between Germany, Spain, and Sweden demonstrates similar gender patterns, even though the role of the state in supporting care differs considerably as do care workers' conditions. The sustainability of today's distribution and organization of care work is questioned as the need for care increases, and the possibility of more equal sharing of care work between women and men is explored.