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Showing 1 to 20 of 81 for “"base material"”.
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Characterization of Recycled Concrete for use as Pavement Base Material
The use of recycled concrete material (RCM) as pavement base material is a promising but unproven technique for road rehabilitation and construction. A telephone survey conducted to investigate the state of the practice concerning RCM usage in Utah County revealed that RCM is infrequently used in …
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Base material electrocatalysts for oxygen cathodes in low temperature acid fuel cells
This thesis investigated the potential use of base material electrocatalysts for the oxygen cathode of a low-temperature acid fuel cell. Pt-based oxygen reduction electrocatalysts have so far been the only materials meeting the requirements of electrocatalytic activity, stability in the acidic …
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Pavement thickness design using reclaimed hydrated Iowa class C fly ash as a base material
… using reclaimed hydrated class C fly ash as a base material. Reclaimed fly ash from four Iowa sources was investigated, in an untreated state as well as stabilized with lime and raw fly ash. Standard tests, including proctor density, gradation, and specific gravity were performed to compare the …
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Nickel-based superalloy operating temperature determination via analysis of gamma/gamma' microstructure and coating/base material interdiffusion
… via [gamma]/[gamma]' microstructure and coating/base metal interdiffusion methods. The [gamma]' volume fraction was measured by point counting and direct area measurement. The data, however, were found inadequate to accurately determine the operating temperature. The interdiffusion between the …
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Use of the Clegg Impact Soil Tester to Access Rutting Susceptiblity of Cement-Treated Base Material Under Early Trafficking
… occurrence of early-age damage, cement-treated base (CTB) materials must be allowed to cure for a period of time before the pavement can be opened to traffic. Trafficking of a CTB before sufficient strength gain has occurred can lead to marring or rutting of the treated layer. The specific …
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Sulfate Leaching from Sulphur Binding Agents in Experimental Asphalt Pavement, Angelina County, Texas
… four layers of a mixture of a single aggregate base material of hot sand, when compared to all other treatments. Analysis of the data showed that the other treatments had no overall effect on the soil sulfates. Four layers of a single aggregate of hot sand increased the quantity of sulfates in …
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Applications of powder interlayers for large gap joining
… of the melting point depressant (MPD) and the base material, from which a great amount of MPD (>30 vol.%) usually has to be used to eliminate residual porosity. To reduce the MPD in the joint, the liquid infiltrated powder interlayer bonding (LIPB) process was developed. For a material system …
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Effects of Friction Stir Welding on Polymer Microstructure
… created for this work maintained 80-92% of base material flexural strength. In the majority of the welds, the strength was between 85 and 90% of base material. The FSW joints showed a flexural strength of 10500 psi, compared to a base material strength of 12400 psi. <p>Four microstructural …
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Microstructure and Mechanical Properties of WE43 Alloy Produced Via Additive Friction Stir Technology
… ratio. Further efforts to save on material use and machining time have focused on the use of additive manufacturing. However, anisotropic properties can be caused by both the HCP structure of magnesium alloys as well as by layered effects left by typical additive manufacturing …
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An Investigation of Improving Wear of 390 Die-cast Aluminum Through Hardcoat Anodizing
… may be reduced by changing the hardness of the materials involved. Archard's equation gave tangible evidence of this fact, but related to the base material and not a surface coating. It was hypothesized that Hardcoat anodizing would follow the theory of Archard's equation and increase the wear …
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Minority Electron Base Transport in Heterojunction Bipolar Transistors Determined by Magneto-Transport Measurements
… of the minority electron mobility in the base of the HBT and the dc current gain of the device. The minority electron lifetime can be determined using these two measurements. Therefore, this technique is very valuable for its ability to characterize the quality of the base material in …
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Fatigue properties of dissimilar metal laser welded lap joints.
… lap face and the early crack growth rate of the material at the internal lap face. The lap joint rotation, in turn, is controlled by sheet thickness, weld width and interfacial gap. Laser welded lap joint fatigue properties are found to be independent of base material properties, allowing …
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The rheology of liquid crystal polymer blends.
… rheological and morphological properties of the base material. This indicates the liquid crystal polymer can be used as a processing aid. A reduction of viscosity was noticed in all of the tests carried out and is attributed to the change in morphology induced by the addition of liquid crystal …
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Friction Stir Welding of High-Strength Automotive Steel
… welds were created in the DP 780 and DP 980 materials. A series of microhardness measurements were taken across weld samples to gain understanding as to the causes of failure. These data indicate that softening, caused by both excessive heat and insufficient heat can result in weld failure. …
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Estudo do comportamento de lastros de materiais granulares sobre estacas com capitéis através de modelos reduzidos
The present work aimed at the behaviour of bases for oil tanks, warehouses and storage yards made of granular material placed over piles with small circular caps. The importance of the following parameters has been evaluated with the aid of a small scale model: critical thickness of the base in …
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Evaluation of jointed plain concrete pavement (JPCP) with FRP dowels
… dowels by varying dowel diameter, spacing, dowel material properties, joint width, and base material properties. (Abstract shortened by UMI.).
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Fabrication and Compressive Behavior of Corrugated Aramid-Epoxy Cellular Solids
<p>Cellular solids are materials whose base material does not always occupy the entire solid fraction available. A number of cellular solids can provide blast protection and absorb impact energy, but few perform well resisting blunt object (ballistic) penetration. In this thesis, a method is …
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Analysis of the Interface Properties of Multi-material 3D Printed Structures
Multi-material 3D printed (MM3DP) samples offer enhanced mechanical performance with the added benefit of being customizable for specific applications. However, MM3DP structures have weak adhesion at the boundary interface. So, the interface characteristics in those structures are a critical factor …
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Application and economic feasibility of functionally graded composite for lead-bismuth service
Use of materials in liquid Pb/Pb-Bi systems in the higher temperature (550°C-700°C) in advanced liquid metal cooled advanced reactor systems is limited by their corrosion resistance. To address this issue, an Fe-12Cr-2.55Si alloy system is being developed and researched, and when used along with …
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The Influence of Reinforcement Architecture on the Fracture Behavior of Selectively Reinforced Materials
A computer-based parametric study of the effect of reinforcement architectures on fracture response of aluminum compact-tension (CT) specimens was performed using the finite element code ABAQUS. A three-dimensional crack propagation procedure based on the crack tip opening angle (CTOA) was …
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