Abstract: A method of non-destructive detection of solid inclusions with varying sensitivities but highly congruent positional identification by both short-wavelength and long-wavelength methods. The short-wavelength method consists of lateral scatter (LS) and the long-wavelength method consists of THz imaging. The LS method was able to detect all agglomerated inclusions, transparency variations, voids, and localized phase differences. The THz imaging was able to routinely detect solid inclusions and index inhomogeneity. In combination, the LS and THz imaging methods were able to detect all relevant types of material variation, so that the combination of the two non-destructive testing methods provides a solution capable of detecting the full array of critical material variations in transparent polycrystalline ceramic materials.
Abstract: A method of non-destructive detection of solid inclusions with varying sensitivities but highly congruent positional identification by both short-wavelength and long-wavelength methods. The short-wavelength method consists of lateral scatter (LS) and the long-wavelength method consists of THz imaging. The LS method was able to detect all agglomerated inclusions, transparency variations, voids, and localized phase differences. The THz imaging was able to routinely detect solid inclusions and index inhomogeneity. In combination, the LS and THz imaging methods were able to detect all relevant types of material variation, so that the combination of the two non-destructive testing methods provides a synergistic solution capable of detecting the full array of critical material variations in transparent polycrystalline ceramic materials.
Abstract: Targets for the fabrication of quasicrystalline films are prepared from powders of the elemental constituents of the objective quasicrystalline material that have been pressed into a required target shape. The temperature of target fabrication is maintained sufficiently low that quasicrystalline alloy formation does not occur during target fabrication. Due to the high thermal shock resistance of each of the individual constituents and due to the dispersed form of the powders comprising the target, the target demonstrates very high resistance to thermal shock.
Abstract: Material compositions for use in orthopedic implants comprising blends of ultra high molecular weight polyethylene (UHMWPE) and hard ceramic powders prepared by blending powdered UHMWPE and the ceramic powder in a high shear mixer are described. Orthopedic implants are then fabricated by pressure/thermo-forming the ceramic/polymer blend into a net shape prosthesis or a rod suitable for subsequently machining the desired components using diamond tooling. Net shape forming is the preferred method for preparing the orthopedic implants.
Type:
Grant
Filed:
June 26, 2000
Date of Patent:
May 6, 2003
Assignee:
Technology Assessment & Transfer, Inc.
Inventors:
Larry Lee Fehrenbacher, Mark Patterson, Walter Zimbeck
Abstract: Non-oxide debond coated reinforcing fibers that are resistant to oxidation at temperatures above about 1200° C. are described. The debond coatings are non-hygroscopic, and exhibit debond performance equal to or better than the prior art such coatings. The coated fibers of the present invention comprise a non-oxide fiber with or without a thin conventionally applied pyrolytic carbon layer overcoated with a non-hygroscopic silicon and titanium containing single or multi-layer structure that imparts all of the properties demanded of a debond coating while additionally providing exceptional oxidation resistance protection.
Type:
Grant
Filed:
April 28, 2000
Date of Patent:
January 14, 2003
Assignee:
Technology Assessment & Transfer, Inc.
Inventors:
Larry Lee Fehrenbacher, Mark Patterson, Dave McQuiston
Abstract: A method for the production of ceramic matrix composites by chemical vapor infiltration. The method includes exposing an infiltrated preform to microwave energy, with pressure variation of the reactant gases in the processing chamber and/or temperature variation of the preform during processing, to produce substantially improved composites. The process provides higher deposition rates within the core of the ceramic matrix composite, higher densification which advantageously initiates within the interior of the ceramic matrix composite and proceeds radially outward, and a thick wall ceramic matrix composite with an overall reduced density gradient.
Type:
Grant
Filed:
March 30, 1992
Date of Patent:
August 24, 1993
Assignee:
Technology Assessment & Transfer, Inc.
Inventors:
Iftikhar Ahmad, Edward L. Paquette, Richard Silberglitt