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Engineering Science and Materials Commons™

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Series

1995

Articles 1 - 6 of 6

Full-Text Articles in Engineering Science and Materials

Process For The Formation Of Wear- And Scuff-Resistant Carbon Coatings, Gerard W. Malaczynski, Xiaohong Qiu, Joseph V. Mantese, Alaa A. Elmoursi, Aboud H. Hamdi, Blake P. Wood, Kevin C. Walter, Michael Nastasi Oct 1995

Process For The Formation Of Wear- And Scuff-Resistant Carbon Coatings, Gerard W. Malaczynski, Xiaohong Qiu, Joseph V. Mantese, Alaa A. Elmoursi, Aboud H. Hamdi, Blake P. Wood, Kevin C. Walter, Michael Nastasi

Department of Mechanical and Materials Engineering: Faculty Publications

A process for forming an adherent diamond-like carbon coating on a workpiece of suitable material such as an aluminum alloy is disclosed. The workpiece is successively immersed in different plasma atmospheres and subjected to short duration, high voltage, negative electrical potential pulses or constant negative electrical potentials or the like so as to clean the surface of oxygen atoms, implant carbon atoms into the surface of the alloy to form carbide com pounds while codepositing a carbonaceous layer on the surface, bombard and remove the carbonaceous layer, and to thereafter deposit a generally amorphous hydrogen-containing carbon layer on the surface …

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Design Of A Structured Light Sensor For In Situ Calibration, Fred W. Depiero, Reid L. Kress Aug 1995

Design Of A Structured Light Sensor For In Situ Calibration, Fred W. Depiero, Reid L. Kress

Electrical Engineering

This paper highlights a ranging sensor that can be calibrated at standoffs of 1 to 3 feet with a depth of field of ≈ 1 ft. Tests at a 16" standoff have produced a 0.004 inch standard deviation in height measurement errors. The data density and field of view are programmable. The sensor is positioned robotically, allowing it to provide accurate, short-range measurements prior to manipulation tasks. The sensor head is relatively inexpensive (≈ $10k) and is designed for in situ calibration. This approach is intended to allow replacement components to be installed, calibrated, and validated without decontamination. Calibration, validation …

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Method Of Making Quasicrystal Alloy Powder, Protectivecoatings And Articles, Jeffrey E. Shield, Alan I. Goldman, Iver E. Anderson, Timothy W. Ellis, R. William Mccallum, Daniel J. Sordelet Jul 1995

Method Of Making Quasicrystal Alloy Powder, Protectivecoatings And Articles, Jeffrey E. Shield, Alan I. Goldman, Iver E. Anderson, Timothy W. Ellis, R. William Mccallum, Daniel J. Sordelet

Department of Mechanical and Materials Engineering: Faculty Publications

A method of making quasicrystalline alloy particulates wherein an alloy is superheated and the meltis atomized to form generally spherical alloy particulates free of mechanical fracture and exhibiting a predominantly quasicrystalline in the atomized condition structure. The particulates can be plasma sprayed to form a coating or consolidated to form an article of manufacture.

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Distortion And Evolution Of A Localized Vortex In An Irrotational Flow, Joseph F. Lingevitch, Andrew J. Bernoff May 1995

Distortion And Evolution Of A Localized Vortex In An Irrotational Flow, Joseph F. Lingevitch, Andrew J. Bernoff

All HMC Faculty Publications and Research

This paper examines the interaction of an axisymmetric vortex monopole, such as a Lamb vortex, with a background irrotational flow. At leading order, the monopole is advected with the background flow velocity at the center of vorticity. However, inhomogeneities of the flow will cause the monopole to distort. It is shown that a shear‐diffusion mechanism, familiar from the study of mixing of passive scalars, plays an important role in the evolution of the vorticity distribution. Through this mechanism, nonaxisymmetric vorticity perturbations which do not shift the center of vorticity are homogenized along streamlines on a Re1/3 time scale, much faster …

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Development Of Nial-Based Intermetallic Alloys: Effect Of Chromium Addition, R. Tiwari, Surendra N. Tewari, R. Asthana, A. Garg Feb 1995

Development Of Nial-Based Intermetallic Alloys: Effect Of Chromium Addition, R. Tiwari, Surendra N. Tewari, R. Asthana, A. Garg

Chemical & Biomedical Engineering Faculty Publications

The mechanical behavior of dual-phase NiAl(Cr) microstructures, consisting of elongated primary NiAl grains aligned with an intergranular NiAl-Cr eutectic phase, produced by extrusion of a cast NiAl(Cr) alloy, has been examined. Chromium addition to create a dual phase NiAl-based aligned microstructure leads to large increases in the yield strength but no significant toughness improvement. This is achieved primarily by solid solution hardening and precipitation hardening. The constitutional hardening rate resulting from deviations from stoichiometry in the nickel-rich NiAl was estimated to be about 66 MPa per atomic per cent of nickel.

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Using Matlab To Illustrate The 'Phenomenon Of Aliasing', Sol Neeman, Ph.D. Jan 1995

Using Matlab To Illustrate The 'Phenomenon Of Aliasing', Sol Neeman, Ph.D.

Engineering Studies Faculty Publications and Creative Works

The phenomenon of aliasing is important when sampling analog signals. In cases where the signal is bandlimited, one can avoid aliasing by ensuring that the sampling rate is higher than the Nyquist rate . But in cases where the signal is not bandlimited , aliasing is unavoidable if the signal is not filtered before it is sampled. It is then crucial to understand the phenomenon in order to estimate the distortion generated when the signal is reconstructed from its samples. Using the software package MATLAB by MathWorks, Inc ., two examples are presented. The first is a pure sinusoid which …

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