Measurement of the noibium/sapphire interface toughness via delamination (2003)
Je, H., Was, Gary S., Thouless, Michael D.
Niobium films were deposited on sapphire substrates using both physical vapor deposition (PVD) and ion beam assisted deposition (IBAD) at an ion energy of 1000 eV and an ion-to-atom arrival rate...
Ion Beam Modification of Surface for Improved High Temperature Performance. (1998)
A novel experimental technique, 'Thin Film Calorimetry' (TFC), has been developed to determine the enthalpy of transformation from metastable to stable equilibrium structures in thin films. This...
Lattice Location and Hardness of Ta-Implanted Ni3Al. (1998)
Was, Gary S., Mantl, Siegfried, Oliver, Warren
Implantation of Ta into single crystal Ni3Al was conducted to determine the degree of surface hardening in monolithic alloys in relation to its lattice location; Ta was implanted at 400 keV to doses...
Hardness-Damage Correlations in Ta Implanted Single Crystal Ni3Al. (1998)
Was, Gary S., Mantl, Siegfried, Oliver, Warren
Implantation of Ta into single crystal Ni3Al was conducted to determine whether this would be an effective means of producing surface hardening in monolithic alloys; Ta was implanted at 400 keV to...
Hardness of Ion-Implanted Ni3Al and TiAl. (1998)
Experiments were conducted to the effect of various implanted species on the hardness of single crystal Ni3Al (Ta, Al, B) and polycrystalline TiAl (Ta, N, B); implantations were conducted to yield...
Effect of Carbon on the Low-Temperature Creep Behavior of Ni-16Cr-9Fe. (1998)
Sung, Jin K., Jones, J. Wayne, Was, Gary S.
The effects of carbon on the low-temperature creep behavior of Ni-16Cr-9Fe were examined; a correlation between IG fracture and grain boundary cavitation and linkup which depends on carbon...
Crawford, Douglas C., Was, Gary S.
The effect of grain boundary misorientation on the intergranular cracking behavior of pure Ni-16Cr-9Fe was assessed by determining if low-angle boundaries (LABs) or coincident site lattice boundaries...
Microchemical and Microstructural Effects on Stress Corrosion Cracking of Nickel-Base Alloys. (1998)
This paper discusses the effects of acidic, caustic, high temperature water, and high temperature argon environments on intergranular cracking in nickel alloys from 22-360 C. Results show that the...
Effects of irradiation on intergranular stress corrosion cracking (1994)
Was, Gary S., Bruemmer, Stephen M.
Intergranular stress corrosion cracking (IASCC) is a pervasive and generic problem in current light water reactor and advanced reactor designs that can lead to widespread component failure. IASCC is...
Bruemmer, Stephen M., Was, Gary S.
This review paper examines mechanisms controlling IGSCC in selected LWR components. Emphasis is placed on identifying material microstructures and microchemistries which promote susceptibility to...
Was, Gary S., Demaree, J. D., Rotberg, V. H., Kim, K.
Ion implantation of AISI 52100 and 1070 steels was conducted in order to improve the corrosion, wear and ultimately the fretting behavior of the steels. Implantations consisted of 1 x 1017 Ta+ cm-2,...
Radiation-induced segregation in multicomponent alloys: Effect of particle type (1994)
The problem of irradiation-assisted stress-corrosion cracking (IASCC) in reactor cores is currently being addressed using different types of particle irradiation (electrons, protons, and heavy ions)...
Was, Gary S., Jones, J.W., Kalnas, C.E., Parfitt, L.J., Goldiner, M.
Multilayer metal-ceramic films have the potential to serve as strong, tough and environmentally resistant films and coatings for a wide variety of applications. They derive their properties from the...
Intercomparison of microchemical evolution under various types of particle irradiation (1993)
The problem of irradiation-assisted stress corrosion cracking (IASCC) in reactor cores is currently being addressed using different types of particle irradiation (electrons, heavy and light ions) to...
Carter, R. D., Damcott, D. L., Atzmon, Michael, Was, Gary S., Kenik, E. A.
A research program has been undertaken to determine the origins of irradiation-assisted stress corrosion cracking (IASCC) in austenitic alloys in light water reactors, and the effect of impurities on...
Irradiation assisted stress corrosion cracking of controlled purity 304L stainless steels (1993)
Cookson, J. M., Damcott, D. L., Atzmon, Michael, Was, Gary S.
The effect of chromium, phosphorus, silicon and sulfur on the stress corrosion cracking of 304L stainless steel in CERT tests in high purity water or argon at 288[deg]C following irradiation with 3.4...
Synthesis and properties of microlaminate structures by ion beam assisted deposition (1993)
Was, Gary S., Jones, J. W., Kalnas, C. E., Parfitt, L. J., Mashayekhi, A., Hoffman, D. W.
Films of Al, Al2O3, Mo and MoSix were formed by ion beam assisted deposition (IBAD) at R ratios between 0.004 and 0.1 and film thicknesses between 150 and 1100 nm. Al films were crystalline with a...
Demaree, J. D., Was, Gary S., Sorensen, N. R.
An experimental program was conducted to determine the mechanisms by which phosphorus affects the corrosion and passivation behavior of Fe-Cr-P alloys. To identify separately the effects of structure...
Application of a thermal spike model to experimental ion-induced grain growth data (1992)
Alexander, Dale E., Was, Gary S.
A model of ion-induced grain growth is developed incorporating the irradiation effect concept of thermal spikes. The results of the model predict that for normal grain growth the ion-induced mobility...
Crawford, Douglas C., Was, Gary S.
Selected area channeling patterns imaged on an SEM are digitized and displayed on the screen of a Macintosh computer, on which the user selects channeling bands that are measured to determine...
Ion-induced grain growth in multilayer and coevaporated metal alloy thin films (1991)
Alexander, Dale E., Was, Gary S., Rehn, L. E.
Irradiation experiments were conducted on multilayer (ML) and coevaporated (CO) thin films in order to examine the role that the heat-of-mixing ([Delta]Hmix) has in ion-induced grain growth....
Demaree, J. D., Was, Gary S., Sorensen, N. R.
An experimental program has been conducted to determine the effect of phosphorus on the corrosion and passivation behavior of Fe---Cr---P alloys. Chemically homogeneous 60 nm films of Fe---10Cr---xP...
Hardness and friction of N2+ and Al+ implanted B4C (1991)
Was, Gary S., DeKoven, Benjamin M.
Surfaces of boron carbide (B4C) were implanted with 200 keV N2+ or 100 keV Al+ ions to a dose of 8 x 1017 cm -2. Ultralow load indentation via the Nanoindenter was used to determine the changes in...
A novel experimental technique has been developed by which metastable phase transformations in thin films may be investigated. The technique is demonstrated by the determination of the enthalpies of...
Cyclic strain localization in ion beam microalloyed nickel (1990)
Morrison, D. J., Jones, J. W., Was, Gary S.
Peer Reviewed
Morrison, D. J., Jones, J. W., Alexander, Dale E., Kovach, C., Was, Gary S.
Flexural fatigue tests at surface strain amplitudes of +/-0.0012 were conducted on polycrystalline nickel to determine the effect of ion beam surface modifications of the Ni/Al system on fatigue...
The Michigan Ion Beam Laboratory for Surface Modification and Analysis (1989)
The Michigan Ion Beam Laboratory for Surface Modification and Analysis was established in October of 1986 for the purpose of advancing our understanding of ion-solid interactions on both the...
Alexander, Dale E., Was, Gary S., Eridon, James
Multilayers of Ni---21Al and Ni---20Cr---10Al were subjected to ion beam mixing using 350 keV Ni+ ions and/or thermal annealing at 440[deg]C to study the development of grain growth and phase...
Ion beam modification of metals: Compositional and microstructural changes (1989)
Ion implantation has become a highly developed tool for modifying the structure and properties of metals and alloys. In addition to direct implantation, a variety of other ion beam techniques such as...
Rotberg, V. H., Perry, A. J., Strandberg, C. C., Was, Gary S.
Charged particle beams have been used to extract data both on the composition and also on the thickness of two series of TiNx films (about 5 and 2 [mu]m thick respectively), where x varied from 0.3...
Kruger, R. M., Was, Gary S., Mansfield, John F., Martin, J. R.
A thermodynamic model has been constructed to explain the details of grain boundary chemistry in Ni-16Cr-9Fe doped with carbon and boron. In this model, Gibbs free energy of the precipitates is...
Laser-driven micro-explosive bonding of aluminium films to copper and silicon (1988)
Was, Gary S., Alexander, Dale E., Mayer, Frederick J.
Laser explosive microfabrication was used to bond micrometre-thick aluminium films to both copper and silicon substrates. Bonding was observed in both systems for laser intensities greater than about...
Metastable phase formation by ion beam mixing (1987)
There are essentially four basic types of metastable alloys which may be formed through heavy ion irradiation of crystalline structures: amorphous phases with no long range order; crystalline phases...
Smith, Richard W., Was, Gary S.
A computational framework for modeling irradiation creep and swelling is developed to estimate creep strains, swelling strains and the dose dependent evolution of microstructural characteristics such...
Automatic iterative fitting of Rutherford backscattering spectra from multielement samples (1985)
A computer code (BASF) has been constructed to perform automatic iterative fitting of Rutherford backscattering spectra using only the experimental spectrum and the parameter set defining the...
A thermodynamic and kinetic basis for understanding chromium depletion in Ni-Cr-Fe alloys (1985)
Thermodynamic and kinetic models are constructed to describe the development of the chromium depleted zone in Ni-Cr-Fe alloys heated in the range 773-1173 K. The models are interactive and constitute...
Improvements in the design and analysis of the segmented expanding mandrel test (1985)
Nobrega, B. N., King, John Swinton, Was, Gary S., Wisner, S. B.
The segmented expanding mandrel test is modified and improved to yield more quantitative information on the local stress and strain concentrations in Zircaloy tubing samples. The experimental...
Nobrega, B. N., King, John Swinton, Was, Gary S., Adamson, R. B.
The segmented expanding mandrel test is modified to provide additional information on the localized stresses and strains during ramp-hold tests. A chamfered specimen is designed with four flats on...
Application of adjoint sensitivity analysis to nuclear reactor fuel rod performance (1984)
Wilderman, Scott J., Was, Gary S.
Adjoint sensitivity analysis in nuclear fuel behavior modeling is extended to operate on the entire power history for both Zircaloy and stainless steel cladding via the computer codes FCODE-ALPHA/SS...
Fatigue crack growth retardation inconel 600 (1984)
Brog, T. K., Jones, J. W., Was, Gary S.
The effect of single-cycle overloads on the subsequent fatigue crack growth behavior of Inconel 600 is studied. Overloads ranging from 10 to 50% are applied to a sample undergoing baseline fatigue...
Adjoint sensitivity analysis in nuclear reactor fuel behavior modeling (1981)
Christensen, Ronald A., Eilbert, Richard F., Rohrer, Ronald A., Was, Gary S.
A computer program, SCODE, has been developed for calculating sensitivities for EPRI's SPEAR-ALPHA nuclear fuel performance code FCODE-ALPHA. Eleven critical parameters are assessed for the effects...