Michael Nastasi

Bio: Michael Nastasi is an academic researcher from Texas A&M University. The author has contributed to research in topics: Amorphous solid & Thin film. The author has an hindex of 55, co-authored 527 publications receiving 15615 citations. Previous affiliations of Michael Nastasi include Los Alamos National Laboratory & Cornell University.

Handbook of modern ion beam materials analysis

Abstract: The Handbook of Modern Ion Beam Materials Analysis, Second Edition is a compilation of updated techniques and data for use in the ion-beam analysis of materials The information presented is unavailable collectively from any other source, and places a strong emphasis on practical examples of the analysis techniques as they are applied to common problems Revised and updated from the popular handbook previously released in 1995, this edition is written and compiled by over 30 leading authorities in the field of ion beam analysis The book is an excellent introduction to the fundamentals and lab practices of ion beam analysis and is also useful as a teaching text for undergraduate senior or first-year graduate students This text is a comprehensive collection of nuclear and atomic data for the applications of ion beam materials analysis In addition, the DVD includes bonus info - both the Ion Beam Analysis Nuclear Data Library (IBANDL) and GUPIX Subroutines (CSA and YLS) for X-ray Database

Efficient annealing of radiation damage near grain boundaries via interstitial emission.

Abstract: Although grain boundaries can serve as effective sinks for radiation-induced defects such as interstitials and vacancies, the atomistic mechanisms leading to this enhanced tolerance are still not well understood With the use of three atomistic simulation methods, we investigated defect-grain boundary interaction mechanisms in copper from picosecond to microsecond time scales We found that grain boundaries have a surprising "loading-unloading" effect Upon irradiation, interstitials are loaded into the boundary, which then acts as a source, emitting interstitials to annihilate vacancies in the bulk This unexpected recombination mechanism has a much lower energy barrier than conventional vacancy diffusion and is efficient for annihilating immobile vacancies in the nearby bulk, resulting in self-healing of the radiation-induced damage

Radiation effects in crystalline ceramics for the immobilization of high-level nuclear waste and plutonium

Abstract: This review provides a comprehensive evaluation of the state-of-knowledge of radiation effects in crystalline ceramics that may be used for the immobilization of high-level nuclear waste and plutonium. The current understanding of radiation damage processes, defect generation, microstructure development, theoretical methods, and experimental methods are reviewed. Fundamental scientific and technological issues that offer opportunities for research are identified. The most important issue is the need for an understanding of the radiation-induced structural changes at the atomic, microscopic, and macroscopic levels, and the effect of these changes on the release rates of radionuclides during corrosion.

Ion-Solid Interactions: Fundamentals and Applications

Abstract: 1. General features and fundamental concepts 2. Interatomic potentials 3. Dynamics of binary elastic collisions 4. Cross-section 5. Ion stopping 6. Ion range and range distribution 7. Radiation damage and spikes 8. Ion-solid simulations and irradiation enhanced transport 9. Sputtering 10. Order-disorder under irradiation and ion implantation metallurgy 11. Ion beam mixing 12. Phase transformations 13. Ion beam assisted deposition 14. Applications of ion beam processing techniques 15. Ion beam system features Appendices: A. Crystallography B. Table of contents C. Density of states D. Derivation of the Thomas-Fermi differential equations E. Centre-of-mass and laboratory scattering angles F. Miedema's semi-empirical model for the enthalpy of formation in the liquid and solid state G. Implantation metallurgy - study of equilibrium alloys.

Mechanical properties and deformation behavior of materials having ultra-fine microstructures

Abstract: Fundamental concepts structure and physical properties mechanical response superplasticity nanoindentation synthesis and processing characterization

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Surface modification of titanium, titanium alloys, and related materials for biomedical applications

Abstract: Titanium and titanium alloys are widely used in biomedical devices and components, especially as hard tissue replacements as well as in cardiac and cardiovascular applications, because of their desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, corrosion resistance, and biocompatibility. However, titanium and its alloys cannot meet all of the clinical requirements. Therefore, in order to improve the biological, chemical, and mechanical properties, surface modification is often performed. This article reviews the various surface modification technologies pertaining to titanium and titanium alloys including mechanical treatment, thermal spraying, sol–gel, chemical and electrochemical treatment, and ion implantation from the perspective of biomedical engineering. Recent work has shown that the wear resistance, corrosion resistance, and biological properties of titanium and titanium alloys can be improved selectively using the appropriate surface treatment techniques while the desirable bulk attributes of the materials are retained. The proper surface treatment expands the use of titanium and titanium alloys in the biomedical fields. Some of the recent applications are also discussed in this paper.