Download or read book The Microstructure and Fatigue Behavior of In situ Directionally Solidified NiAl Cr Mo Eutectic Composite written by Kirk Beng-Tek Cheng and published by . This book was released on 1996 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Processing and Mechanical Properties of NiAl based In situ Composites written by David Ray Johnson and published by . This book was released on 1994 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microstructure and Fatigue Behavior of Three Nickel Base Eutectic Composites written by K. A. Dannemann and published by . This book was released on 1982 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: The high cycle fatigue behavior of three advanced unidirectionally solidified nickel-base eutectic alloys has been studied. AG-170, strengthened by Alpha-Mo fibers, and brittle carbide reinforced Nitac 14B and Cotac 744 were tested in vacuum under axial tension-tension, sinusoidal loading at 20 Hz. Fatigue properties of the as D.S. and heat treated conditions were examined at both 25 deg C and 825 deg C. In addition, the effects of reduced frequency on the high temperature fatigue life of aged Nitac 14B have been determined. Fatigue resistance of the as D.S. material decreased between 25 deg C and 825 deg C. This has been related to a variation in the mode of cracking. Room temperature failures were surface initiated and propagation proceeded along crystallographic planes, wheras Stage II crack propagation was observed at 825 deg C. Nitac 14B was shown to be superior at both temperatures owing to its high matrix strength and large Gamma' volume fraction. The elevated temperature fatigue life of aged Nitac 14B was substantially reduced at low test frequencies in vacuum. The decrease in frequency caused a shift from surface initiated failure to an almost featureless fracture surface where the initiation, fatigue, and overload zones were not easily identified. Reduced specimen life was postulated to be the result of enhanced creep.

Download or read book Microstructure and Fatigue Behavior of Three Ni base Eutectic Composites written by Kathryn A. Dannemann and published by . This book was released on 1982 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Efficient fast Fourier transform based solvers for computing the thermomechanical behavior of applied materials written by Wicht, Daniel and published by KIT Scientific Publishing. This book was released on 2022-10-11 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mechanical behavior of many applied materials arises from their microstructure. Thus, to aid the design, development and industrialization of new materials, robust computational homogenization methods are indispensable. The present thesis is devoted to investigating and developing FFT-based micromechanics solvers for efficiently computing the (thermo)mechanical response of nonlinear composite materials with complex microstructures.

Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2018 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fatigue Behavior in Torsion of an Unidirectionally Solidified Eutectic written by W. G Ovens (Jr) and published by . This book was released on 1972 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fatigue behavior of the directionally-solidified eutectic-alloy Al-Al3Ni was studied under cyclic-torsional loading. The fatigue process is largely confined to the matrix, with the rod-like reinforcing phase influencing the crack path. Grain boundaries are foung to be preferred sites for cracking. An observed cyclic softening process is related to the initial distribution of dislocations along the fibers. A surface wrinkling effect is the result of a second-order effect in cyclic torsion. Fatigue properties of the composite are better than might be expected on the basis of axial tests. (Author).

Download or read book Metals Abstracts written by and published by . This book was released on 1998 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Directional Solidification Microstructures and Mechanical Properties of Cr Cr3Si Eutectic Alloys written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Alloys based on intermetallics have been considered for high temperature structural applications. However, many of these alloys suffer from intrinsic brittleness and low fracture toughness at ambient temperature. Therefore, ductile-phase-toughened intermetallic composites are being investigated as a means to improve the fracture toughness. A subset of this class of materials is in-situ composites produced by directional solidification of intermetallic eutectics. In this study, the Cr-Cr3Si eutectic system is selected as a model system to investigate composites by directional solidification, where the strong, but brittle Cr3Si is combined with a more ductile Cr-rich solid solution. A series of binary Cr-Si alloys with silicon concentrations ranging from 13 to 24 at.% were produced by arc melting and drop casting. These compositions span the composition (15 at.% Si) at which a eutectic reaction is reported in the phase diagram. The microstructure of the Cr-16.05 at.% Si alloy is fully lamellar and devoid of any proeutectic phases suggesting that the best composition for obtaining a fully lamellar structure is Cr-16.05 at.% Si rather than the eutectic composition (Cr-15 at.% Si) indicated in the phase diagram. The eutectic microstructure consists of alternating lamellae of Cr (solid solution) and Cr3Si (intermetallic). Uniform and well-aligned lamellar structures were obtained over a fairly wide range of solidification conditions, but not at very low or very high growth rates where degenerate and cellular structures, respectively, were obtained. The lamellar spacing was found to increase with decreasing solidification rate, in agreement with the Jackson-Hunt theory. In addition, for a fixed growth rate, the lamellar spacing was found to increase with increasing rotation rate. The growth directions in the lamellar eutectic were found to be 100 for the Cr3Si phase and 111 for the Cr solid solution phase. Eutectic microstructures (rod or lamellar) could also be produced at off-eutectic compositions, but only for a limited range of growth conditions. The mechanical properties of the individual lamellae and the Cr-Cr3Si composites were examined by nanoindentation, Vicker's hardness testing and three-point bend testing. It was found that the Vicker's hardness of Cr-Cr3Si composites is about HV847, independent of the lamellar spacing. The Young's modulus of the Cr-Cr3Si eutectic composites measured by ultrasonic techniques is 312 GPa, which is in reasonably good agreement with the nanoindentation results (within 5%). The fracture toughness of single crystals of Cr3Si is very low (2.6 MPa[square root]m).

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Engineering Index Annual written by and published by . This book was released on 1988 with total page 2282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since its creation in 1884, Engineering Index has covered virtually every major engineering innovation from around the world. It serves as the historical record of virtually every major engineering innovation of the 20th century. Recent content is a vital resource for current awareness, new production information, technological forecasting and competitive intelligence. The world?s most comprehensive interdisciplinary engineering database, Engineering Index contains over 10.7 million records. Each year, over 500,000 new abstracts are added from over 5,000 scholarly journals, trade magazines, and conference proceedings. Coverage spans over 175 engineering disciplines from over 80 countries. Updated weekly.

Download or read book Metals Abstracts Index written by and published by . This book was released on 1995 with total page 1390 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Solidification Processing written by Merton C. Flemings and published by McGraw-Hill Companies. This book was released on 1974 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applied Science Technology Index written by and published by . This book was released on 2000 with total page 1688 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Superplasticity in Metals and Ceramics written by T. G. Nieh and published by Cambridge University Press. This book was released on 1997-01-23 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes advances in the field of superplasticity, the ability of certain materials to undergo very large tensile strains. This phenomenon has increasing commercial applications, but also presents a fascinating scientific challenge in attempts to understand the physical mechanisms that underpin it. The authors emphasize the materials aspects of superplasticity. Beginning with a brief history of the phenomenon, they describe the two major types of superplasticity-- fine-structure and internal-stress superplasticity-- and discuss their operative mechanisms. They also present microstructural factors controlling the ductility and fracture in superplastic materials. Observations of superplasticity in metals (including aluminum, magnesium, iron, titanium and nickel), ceramics (including monoliths and composites), intermetallics (including iron, nickel, and titanium base), and laminates are thoroughly described. This is a valuable text for graduate students and researchers in materials science and engineering.

Download or read book Carbon Nanotubes written by Andy Nieto and published by CRC Press. This book was released on 2021-05-18 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: This discovery of carbon nanotubes (CNT) three decades ago ushered in the technological era of nanotechnology. Among the most widely studied areas of CNT research is their use as structural reinforcements in composites. This book describes the development of CNT reinforced metal matrix composites (CNT-MMCs) over the last two decades. The field of CNT-MMCs is abundant in fundamental science, rich in engineering challenges and innovations and ripe for technological maturation and commercialization. The authors have sought to present the current state of the-art in CNT-MMC technology from their synthesis to their myriad potential end-use applications. Specifically, topics explored include: • Advantages, limitations, and evolution of processing techniques used to synthesize and fabricate CNT-MMCs • Emphasizes dispersion techniques of CNTs in metallic systems, a key challenge to the successful and widespread implementation of CNT-MMCs. Methods for quantification and improved control of CNT distributions are presented • Methods for quantification and improved control of CNT distributions are presented • Characterization techniques uniquely suited for charactering these nanoscale materials and their many chemical and physical interactions with the metal matrix, including real-time in-situ characterization of deformation mechanisms • Electron microscope images from premier studies enrich discussions on micro-mechanical modeling, interfacial design, mechanical behavior, and functional properties • A chapter is dedicated to the emergence of dual reinforcement composites that seek to enhance the efficacy of CNTs and lead to material properties by design This book highlights seminal findings in CNT-MMC research and includes several tables listing processing methods, associated CNT states, and resulting properties in order to aid the next generation of researchers in advancing the science and engineering of CNT-MMCs. In addition, a survey of the patent literature is presented in order to shed light on what the first wave of CNT-MMC commercialization may look like and the challenges that will have to be overcome, both technologically and commercially.