Patents by Inventor John J. Petrovic
John J. Petrovic has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 10290752Abstract: The structures of base semiconductor materials such as Si are modified by the use of isotope transmutation alloying. A radioisotope such as Si31 is added into a base semiconductor material such as Si, and the radioisotope is transformed to a transmuted form within the crystal lattice structure of the base semiconductor material. A master alloy comprising a relatively large amount of radioisotope such as Si31 may initially be made, followed by introduction of the master alloy into the base semiconductor material. When Si31 is used as the radioisotope, it may be transmuted into P31 within an Si crystal lattice structure. Metastable semiconductor materials doped with otherwise insoluble amounts of selected dopants are produced as a result of the transmutation process.Type: GrantFiled: May 4, 2017Date of Patent: May 14, 2019Assignee: ST3 LLCInventors: A. K. Vasudevan, John J. Petrovic, Timothy J. Langan
-
Patent number: 6613276Abstract: Alloys of transition metal suicides that contain one or more alloying elements are fabricated by a two-stage process involving mechanical activation as the first stage and densification and field-activated reaction as the second stage. Mechanical activation, preferably performed by high-energy planetary milling, results in the incorporation of atoms of the alloying element(s) into the crystal lattice of the transition metal, while the densification and field-activated reaction, preferably performed by spark plasma sintering, result in the formation of the alloyed transition metal silicide. Among the many advantages of the process are its ability to accommodate materials that are incompatible in other alloying methods.Type: GrantFiled: April 16, 2002Date of Patent: September 2, 2003Assignee: The Regents of the University of CaliforniaInventors: Zuhair A. Munir, Joseph N. Woolman, John J. Petrovic
-
Patent number: 6300265Abstract: Molybdenum disilicide/&bgr;′-Si6−zAlzOzN8−z, wherein z=a number from greater than 0 to about 5, composites are made by use of in situ reactions among &agr;-silicon nitride, molybdenum disilicide, and aluminum. Molybdenum disilicide within a molybdenum disilicide/&bgr;′-Si6−zAlzOzN8−z eutectoid matrix is the resulting microstructure when the invention method is employed.Type: GrantFiled: June 22, 2000Date of Patent: October 9, 2001Assignee: Regents of the University of CaliforniaInventors: Robert P. Rodriguez, John J. Petrovic
-
Patent number: 6197247Abstract: Molybdenum disilicide/&bgr;′-Si6-zAlzOzN8-z, wherein z=a number from greater than 0 to about 5, composites are made by use of in situ reactions among &agr;-silicon nitride, molybdenum disilicide, and aluminum. Molybdenum disilicide within a molybdenum disilicide/&bgr;′-Si6-zAlzOzN8-z eutectoid matrix is the resulting microstructure when the invention method is employed.Type: GrantFiled: May 26, 1998Date of Patent: March 6, 2001Assignee: The Regents of the University of CaliforniaInventors: Robert P. Rodriguez, John J. Petrovic
-
Patent number: 5928583Abstract: Process for making graded porosity ceramics. A process for making graded porosity ceramics is described which includes the steps of placing a chosen amount of ceramic powder into a mold, compacting the ceramic powder into a green body, applying at least one sintering aid precursor to at least one chosen surface of the green body, allowing the at least one sintering aid precursor to penetrate the at least one surface within a chosen volume of the green body, heating the green body, whereby the sintering precursor generates a sintering aid, and hot pressing and sintering the heated body at a temperature whereby the green body is transformed into the sintered ceramic object.Type: GrantFiled: May 29, 1997Date of Patent: July 27, 1999Assignee: The Reagents of the University of CaliforniaInventors: Kenneth J. McClellan, John J. Petrovic, Ivar E. Reimanis
-
Patent number: 5382553Abstract: Compositions consisting essentially of molybdenum disilicide, silicon carbide, and a zirconium oxide component. The silicon carbide used in the compositions is in whisker or powder form. The zirconium oxide component is pure zirconia or partially stabilized zirconia or fully stabilized zirconia.Type: GrantFiled: February 2, 1994Date of Patent: January 17, 1995Assignee: The Regents of the University of CaliforniaInventor: John J. Petrovic
-
Patent number: 5069841Abstract: Compositions of matter consisting of matrix materials having silicon carbide dispersed throughout them and methods of making the compositions. A matrix material is an alloy of an intermetallic compound, molybdenum disilicide, and at least one secondary component which is a refractory silicide. The silicon carbide dispersant may be in the form of VLS whiskers, VS whiskers, or submicron powder or a mixture of these forms.Type: GrantFiled: August 9, 1990Date of Patent: December 3, 1991Assignee: University of CaliforniaInventors: John J. Petrovic, Richard E. Honnell, W. Scott Gibbs
-
Patent number: 5064789Abstract: Compositions of matter comprised of silicon nitride and molybdenum disilicide and methods of making the compositions, where the molybdenum disilicide is present in amounts ranging from about 5 to about 50 vol. %.Type: GrantFiled: September 27, 1990Date of Patent: November 12, 1991Assignee: The United States of America as represented by the United States Department of EnergyInventors: John J. Petrovic, Richard E. Honnell
-
Patent number: 5063182Abstract: Compositions of matter comprised of molybdenum disilicide and zirconium oxide in one of three forms: pure, partially stabilized, or fully stabilized and methods of making the compositions. The stabilized zirconia is crystallographically stabilized by mixing it with yttrium oxide, calcium oxide, cerium oxide, or magnesium oxide and it may be partially stabilized or fully stabilized depending on the amount of stabilizing agent in the mixture.Type: GrantFiled: August 31, 1990Date of Patent: November 5, 1991Assignee: The United States of America as represented by the United States Department of EnergyInventors: John J. Petrovic, Richard E. Honnell
-
Patent number: 5000896Abstract: A composition consisting of an intermetallic compound, molybdenum disilicide, which is reinforced with VS silicon carbide whiskers dispersed throughout it and a method of making the reinforced composition. Use of the reinforcing material increases fracture toughness at low temperatures and strength at high temperatures, as compared to pure molybdenum disilicide.Type: GrantFiled: March 15, 1990Date of Patent: March 19, 1991Assignee: The United States of America as represented by the United States Department of EnergyInventors: John J. Petrovic, David H. Carter, Frank D. Gac
-
Patent number: 4970179Abstract: Compositions of matter consisting of matrix matrials having silicon carbide dispersed throughout them and methods of making the compositions. A matrix material is an alloy of an intermetallic compound, molybdenum disilicide, and at least one secondary component which is a refractory silicide. The silicon carbide dispersant may be in the form of VLS whiskers, VS whiskers, or submicron powder or a mixture of these forms.Type: GrantFiled: January 9, 1990Date of Patent: November 13, 1990Assignee: The United States of America as represented by the United States Department of EnergyInventors: John J. Petrovic, Richard E. Honnell, W. Scott Gibbs
-
Patent number: 4927792Abstract: A composition consisting of an intermetallic compound, molybdenum disilicide, which is reinforced with VS silicon carbide whiskers dispersed throughout it and a method of making the reinforced composition. Use of the reinforcing material increases fracture toughness at low temperatures and strength at high temperatures, as compared to pure molybdenum disilicide.Type: GrantFiled: June 5, 1989Date of Patent: May 22, 1990Assignee: The United States of America as represented by the United States Department of EnergyInventors: John J. Petrovic, David H. Carter, Frank D. Gac