Peter Kenesei | Argonne National Laboratory (original) (raw)

Papers by Peter Kenesei

Journal of Applied Crystallography, 2016

Metallurgical and Materials Transactions A, 2016

Materials Characterization, 2016

Journal of Applied Physics, 2016

Scripta Materialia, Oct 1, 2005

A mean-field and a multiscale model of a particle reinforced metal-matrix composite were develope... more A mean-field and a multiscale model of a particle reinforced metal-matrix composite were developed based on the knowledge of its three-dimensional microstructure obtained by holotomography. Both the mean-field and the multiscale model accounting for the distribution of particlesÕ local volume fractions approximate well the experimental stress-strain curves.

$Research paper thumbnail of Combined near- and far-field high-energy diffraction microscopy dataset for Ti-7Al tensile specimen elastically loaded in situ$

Integrating Materials and Manufacturing Innovation, 2016

57th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, 2016

Acta Materialia, Jun 1, 2006

A new approach for the estimation of the effective properties of real particle-reinforced metal-m... more A new approach for the estimation of the effective properties of real particle-reinforced metal-matrix composites is presented. The methodology relies on statistical functions of the three-dimensional structure of the composites, as obtained from microtomographic investigations, and uses an ergodic principle for the calculation of the overall properties. Based on the symmetrical functional form of the local volume fraction and results of finite element calculations we develop the so-called ''mean window technique'', which leads to the remarkable result that the effective linear or nonlinear mechanical properties of a composite can be obtained by averaging randomly selected windows from the real structure. Such windows should have a size at least equal to the correlation length of the microstructure and the volume fraction of the particles equal to the mean value of the distribution of the local volume fraction.

A study of the stress gradient developed in a Ti-7AL sample is examined using the technique of Hi... more A study of the stress gradient developed in a Ti-7AL sample is examined using the technique of High-Energy Diffraction Microscopy. The experiment is conducted at beamline 1-ID of the Advanced Photon Source of Argonne National Laboratory, using high-resolution monochromator. A map of grain orientation in the cross-section of the sample is determined through use of a near-fi eld technique. The near-fi eld study is complemented by analysis using data from a far-fi eld detector to develop lattice strain on a grain-by-grain basis. A state of bending with superposed tension is revealed through correlation of the near-fi eld grain map with the far-fi eld center of mass result. A comparison of "macro" stress and the "grain scale" stresses is featured. An assessment is given on the benefi ts and limitations of using the high-resolution monochromator in the strain analysis of far-fi eld detector images.

Medical Applications of Radiation Detectors V, 2015

Journal of Materials Research, 2015

ABSTRACT High performance materials that can withstand radiation, heat, multiaxial stresses, and ... more ABSTRACT High performance materials that can withstand radiation, heat, multiaxial stresses, and corrosive environment are necessary for the deployment of advanced nuclear energy systems. Nondestructive in situ experimental techniques utilizing high energy x-rays from synchrotron sources can be an attractive set of tools for engineers and scientists to investigate the structure-processing-property relationship systematically at smaller length scales and help build better material models. In this study, two unique and interconnected experimental techniques, namely, simultaneous small-angle/wide-angle x-ray scattering (SAXS/WAXS) and far-field high-energy diffraction microscopy (FF-HEDM) are presented. The changes in material state as Fe-based alloys are heated to high temperatures or subject to irradiation are examined using these techniques.

Current Opinion in Solid State and Materials Science, 2014

ABSTRACT An important advance in understanding the mechanics of solids over the last 50 years has... more ABSTRACT An important advance in understanding the mechanics of solids over the last 50 years has been development of a suite of models that describe the performance of engineering materials while accounting for internal fluctuations and anisotropies (ex., anisotropic response of grains) over a hierarchy of length scales. Only limited engineering adoption of these tools has occurred, however, because of the lack of measured material responses at the length scales where the models are cast. Here, we demonstrate an integrated experimental capability utilizing high energy X-rays that provides an in situ, micrometer-scale probe for tracking evolving microstructure and intergranular stresses during quasi-static mechanical testing. We present first-of-a-kind results that show an unexpected evolution of the intergranular stresses in a titanium alloy undergoing creep deformation. We also discuss the expectation of new discoveries regarding the underlying mechanisms of strength and damage resistance afforded by this rapidly developing X-ray microscopy technique.

Advances in X-Ray/EUV Optics and Components IX, 2014

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$Research paper thumbnail of Demonstration of near Field High Energy X-Ray Diffraction Microscopy on High-Z Ceramic Nuclear Fuel Material$

Materials Science Forum, 2014

ABSTRACT Near-field high energy x-ray diffraction microscopy (nf-HEDM) and high energy x-ray micr... more ABSTRACT Near-field high energy x-ray diffraction microscopy (nf-HEDM) and high energy x-ray micro-tomography (μT) have been utilized to characterize the pore structure and grain morphology in sintered ceramic UO2 nuclear fuel material. μT successfully images pores to 2-3μm diameters and is analyzed to produce a pore size distribution. It is apparent that the largest number of pores and pore volume in the sintered ceramic are below the current resolution of the technique, which might be more appropriate to image cracks in the same ceramics. Grain orientation maps of slices determined by nf-HEDM at 25 μm intervals are presented and analyzed in terms of grain boundary misorientation angle. The benefit of these two techniques is that they are non-destructive and thus could be performed before and after processes (such as time at temperature or in-reactor) or even in-situ.

$Research paper thumbnail of Combined high-energy synchrotron X-ray diffraction and computed tomography to characterize constitutive behavior of silica sand$

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2014