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Additive manufacturing (AM) is commonly defined as the production of a functional engineering component built one layer at a time from computer aided design (CAD) data. Applicable metal AM technologies [...]

Demand for power is growing everyday, mainly due to emerging economies in countries such as China, Russia, India, and Brazil. During the last 50 years steam pressure and temperature in power plants have been continuously raised to improve thermal efficiency. Recent efforts to improve efficiency leads to the development of a new generation of heat recovery steam generator, where the Benson once-through technology is applied to improve the thermal efficiency. The main purpose of this paper is to analyze the mechanical behavior of a high pressure superheater manifold by applying finite element modeling and a finite element analysis with the objective of analyzing stress propagation, leading to the study of damage mechanism, e.g., uniaxial fatigue, uniaxial creep for life prediction. The objective of this paper is also to analyze the mechanical properties of the new high temperature resistant materials in the market such as 2Cr Bainitic steels (T/P23 and T/P24) and also the 9-12Cr Martensitic steels (T/P91, T/P92, E911, and P/T122). For this study the design rules for construction of power boilers to define the geometry of the HPSH manifold were applied. [DOI: 10.1115/1.3204563] Keywords: heat recovery steam generator, Benson once-through technology, finite element modeling, finite element analysis, stress analysis, uniaxial fatigue life assessment, uniaxial creep life assessment, steel alloy mechanical properties, 2 1/4 Cr Bainitic steels, 9-12Cr Martensitic steels

The Oak Ridge National Laboratory. (ORNL) has been involved in research and development related to improved performance of recuperators for industrial gas turbines since about 1996, and in improving recuperators for advanced microturbines since 2000. Recuperators are compact, high efficiency heat-exchangers that improve the efficiency of smaller gas turbines and microturbines. Recuperators were traditionally made from 347 stainless steel and operated below or close to 650[degrees]C, but today are being designed for reliable operation above 700[degrees]C. The Department of Energy (DOE) sponsored programs at ORNL have helped defined the failure mechanisms in stainless steel foils, including creep due to fine grain size, accelerated oxidation due to moisture in the hot exhaust gas, and loss of ductility due to aging. ORNL has also been involved in selecting and characterizing commercial heat-resistant stainless alloys, like HR120 or the new AL20-25+Nb, that should offer dramatically improved recuperator capability and performance at a reasonable cost. This paper summarizes research on sheets and foils of such alloys over the last few years, and suggests the next likely stages for manufacturing recuperators with upgraded performance for the next generation of larger 200-250 kW advanced microturbines.

The increasing worldwide demand for oil and gas coupled with the fact that the peak of oil production has been reached or soon will be, has pushed the petroleum industry […]

High-strength face insert materials are key to improving performance of golf club woods and irons, because they permit the design of heads that are lighter, larger, and offer greater energy […]

Byline: D. Biermann, K. Weinert, T. Jansen, M. Noyen High alloyed steels are used in areas where special material properties are demanded. Providing a high strength and a high wear resistance, these steel's main application area is forming technology, e.g., for dies or plungers. The mentioned material characteristics and the required high shape and surface quality result in a difficult machinability of these hard materials. This machining process is mostly performed by grinding, applying highly efficient and wear-resistant Cubical Boron Nitride (CBN) grinding wheels. On the one hand, when grinding frequently changing profile shapes, the use of conventional grinding abrasives, such as fused corundum, is more economic because the grinding wheels can be profiled easily. On the other hand, a toroidic CBN grinding wheel, in combination with an NC-shape grinding process, has a large flexibility pertaining to the grinding of free-form surfaces. In addition the utilisation of the Finite Element Analysis (FEA) for the two grinding processes is presented.

Research has been conducted into the effects of particle size on the core losses of soft magnetic materials. Various types of micro PM BLDC motors, produced with solid hog-out alloy steel, laminated alloy steel and Metal Injection Molding alloy steel powders have been studied. The results show that the core loss of micro PM BLDC motors made by the MIM technique is in the acceptable level when compared with the laminated core motor. Index Terms--Core losses, micro PM BLDC motor, MIM technology, soft magnetic material.

NASCAR and NHRA drivers will square off against one another in a race that has it all - speed, danger, technique, high-performance machines, and merciless punishment for mistakes - in […]