The Experts below are selected from a list of 93 Experts worldwide ranked by ideXlab platform
Matt Cullin - One of the best experts on this subject based on the ideXlab platform.
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modeling and simulation of Constituent Particle clustering and distribution in rolled aluminum alloys
Modelling and Simulation in Materials Science and Engineering, 2011Co-Authors: Matt Cullin, D G Harlow, R P WeiAbstract:It is recognized that corrosion damage in aluminum alloys is the direct result of local galvanic coupling between Constituent Particles and the metal matrix. Heavily clustered groups of Constituent Particles have been shown to form the most severe corrosion pits, and the morphology of these pits has been found to exhibit a strong correlation with that of the instigating Particle cluster. To predict damage evolution accurately in three dimensions, the spatial distribution of the Constituent Particles in a given material must be quantified. The tomographic reconstruction methods currently available are time consuming and possess characteristic length scales that are insufficient for large-scale corrosion studies. To accommodate this larger length scale, a model for three-dimensional Constituent Particle microstructure is proposed. This model employs a fusion of classic stereological techniques and qualitative observations to describe the Constituent Particle microstructure of rolled aluminum alloys in three dimensions. A method is described for generating statistically representative three-dimensional Constituent Particle microstructure from two-dimensional orthogonal cross sections. This novel simulation algorithm allows for detailed three-dimensional Particle microstructure simulations to be carried out using standard optical microscopy and image analysis techniques.
B M Hillberry - One of the best experts on this subject based on the ideXlab platform.
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effects of Constituent Particle clusters on fatigue behavior of 2024 t3 aluminum alloy
International Journal of Fatigue, 1998Co-Authors: E A Debartolo, B M HillberryAbstract:Abstract Fatigue tests of 2024-T3 aluminum sheet were run to determine the effects of Constituent Particles and Particle clusters on fatigue life for all three metallurgical planes. In addition, a model to account for crack coalescence within Particle clusters was developed to determine if Particle clusters can be more damaging than single Particles as crack nucleation sites. On the LS and ST planes, cracks formed primarily at single Particles or holes, indicating that coalescence was not an issue. On the LT plane, coalescence was observed when the Particle clusters were aligned with the crack growth direction, and the life was reduced about 30%. The crack coalescence and growth model showed that varying the initial separation between two Particles (potential cracks) causes at most about a 15–20% change in fatigue life over a separation range of 5 μm to 1200 μm for a pair of 50 μm 2 Particles.
R P Wei - One of the best experts on this subject based on the ideXlab platform.
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modeling and simulation of Constituent Particle clustering and distribution in rolled aluminum alloys
Modelling and Simulation in Materials Science and Engineering, 2011Co-Authors: Matt Cullin, D G Harlow, R P WeiAbstract:It is recognized that corrosion damage in aluminum alloys is the direct result of local galvanic coupling between Constituent Particles and the metal matrix. Heavily clustered groups of Constituent Particles have been shown to form the most severe corrosion pits, and the morphology of these pits has been found to exhibit a strong correlation with that of the instigating Particle cluster. To predict damage evolution accurately in three dimensions, the spatial distribution of the Constituent Particles in a given material must be quantified. The tomographic reconstruction methods currently available are time consuming and possess characteristic length scales that are insufficient for large-scale corrosion studies. To accommodate this larger length scale, a model for three-dimensional Constituent Particle microstructure is proposed. This model employs a fusion of classic stereological techniques and qualitative observations to describe the Constituent Particle microstructure of rolled aluminum alloys in three dimensions. A method is described for generating statistically representative three-dimensional Constituent Particle microstructure from two-dimensional orthogonal cross sections. This novel simulation algorithm allows for detailed three-dimensional Particle microstructure simulations to be carried out using standard optical microscopy and image analysis techniques.
Michael D. Sangid - One of the best experts on this subject based on the ideXlab platform.
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Measuring fatigue crack deflections via cracking of Constituent Particles in AA7050 via in situ x-ray synchrotron-based micro-tomography
International Journal of Fatigue, 2018Co-Authors: Stephen T. Carter, John Rotella, Ronald F. Agyei, Xiaghui Xiao, Michael D. SangidAbstract:Abstract Brittle Constituent Particles play a significant role in the fatigue behavior of 2XXX and 7XXX series aluminum alloys. In this work, in situ fatigue crack growth combined with x-ray synchrotron computed micro-tomography (μXSCT) characterization is used to observe and quantify three dimensional propagating fatigue cracks interacting with Constituent Particles. A relationship is observed with the size of the Constituent Particle ahead of the crack tip and the maximum distance the crack path deflects to interact with the Particle. This crack deflection behavior agrees with the Murakami and Endo model, for the effect of small defects on fatigue performance. A stress field analysis, based on (i) an Eshelby inhomogeneity solution of a perfectly bonded Particle, and (ii) a cracked Particle, based on the Westergaard solution, indicates the stress concentration developed by the presence of a Constituent Particle contributes to crack path deflections. This finding has implications for modeling fatigue crack growth in AA7050-T7451, specifically in determining the actual crack length in terms of a tortuous crack topography, as opposed to a flat projected length.
Rajiv S. Mishra - One of the best experts on this subject based on the ideXlab platform.
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Effect of tool rotation rate on Constituent Particles in a friction stir processed 2024Al alloy
Materials Letters, 2015Co-Authors: Somayeh Pasebani, Indrajit Charit, Rajiv S. MishraAbstract:Abstract Friction stir processing (FSP) carried out on a commercial AA2024Al alloy using different tool rotation rates (200–1000 rpm) led to significant change in size and morphology of the Constituent Particles. The size of insoluble Al 6 (Cu,Mn,Fe) Particles presentin the stir zone was substantially reduced as a function of tool rotation rate whereas smaller soluble Al–Cu–Mg based Particles exhibited significant reduction in amount only at higher tool rotation rates. Severe plastic deformation, peak temperature and Constituent Particle characteristics influenced their evolution.