Patents by Inventor John F. MacDowell

John F. MacDowell 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: 5534470
    Abstract: This invention is directed to the production of thermally crystallizable glasses which, upon heat treatment in contact with alumina particulates, will form a strong glass-ceramic-bonded composite body, the excellent bonding being attributed to the presence of lithium aluminoborate crystals. The glass-ceramic composition consists essentially, in weight percent, of______________________________________ SiO.sub.2 25-55 MgO 0-12 B.sub.2 O.sub.3 35-65 Li.sub.2 O + MgO 4-16. Li.sub.
    Type: Grant
    Filed: October 27, 1994
    Date of Patent: July 9, 1996
    Assignee: Corning Incorporated
    Inventors: Ronald l. Andrus, John F. MacDowell
  • Patent number: 5298332
    Abstract: An article of manufacture comprising protectively coated titanium, titanium alloy or titanium aluminide, and a method for making it, wherein the protective coating is an adherent crystalline alkaline earth silicate glass-ceramic coating having a composition consisting essentially, in weight percent on the oxide basis, of about 20-75% total of oxides selected in amounts not exceeding the indicated proportions from the group consisting of up to about 50% BaO, 55% SrO, and 35% CaO, 25-60% of SiO.sub.2 and, as optional constituents, 0-25% MnO, 0-20% MgO, and 0-30% total of other compatible bivalent and trivalent metal oxides. The coating is applied as a continuous glassy coating and is converted to a crystalline glass-ceramic coating by heat treatment.
    Type: Grant
    Filed: November 15, 1991
    Date of Patent: March 29, 1994
    Assignee: Corning Incorporated
    Inventors: Ronald L. Andrus, John F. MacDowell
  • Patent number: 5256603
    Abstract: This invention is directed to the formation of glass bonded ceramic composite articles, with particular emphasis on forming abrasive products such as grinding wheels. The glasses consist essentially, in weight percent of 15-35% CaO, 35-55% B.sub.2 O.sub.3, and 10-35% SiO.sub.2, with alumina comprising the preferred abrasive particles being bonded into an abrasive product.
    Type: Grant
    Filed: November 19, 1992
    Date of Patent: October 26, 1993
    Assignee: Corning Incorporated
    Inventors: Ronald L. Andrus, John F. MacDowell, Linda R. Pinckney
  • Patent number: 5250360
    Abstract: There is disclosed a coated article composed of a metal alloy substrate, the metal alloy having a nickel, chromium, cobalt or iron base, and a coating that serves as an oxygen barrier to insulate the metal surface from oxygen attack at temperatures which may range up to 1200.degree. C. The coating comprises a glass-ceramic selected from barium silicate and strontium silicate systems characterized by additives that enable forming a continuous well flowed glass coating prior to setting of the coating by crystallization. These additives include the refractory oxides Al.sub.2 O.sub.3, ZrO.sub.2 and Y.sub.2 O.sub.3, the transition metal oxides MnO, CoO, NiO and FeO, and MgO.
    Type: Grant
    Filed: November 16, 1987
    Date of Patent: October 5, 1993
    Assignee: Corning Incorporated
    Inventors: Ronald L. Andrus, John F. MacDowell
  • Patent number: 5153070
    Abstract: For protection against oxidation or other adverse chemical deterioration, substrates such as carbon, intermetallic aluminides, and refractory metal alloys are provided with barrier coatings of an aluminoborate glass-ceramic coating having a composition, in weight percent, of about 10-55% Al.sub.2 O.sub.3, 4-40% B.sub.2 O.sub.3, up to 70% total of RO, wherein RO consists of one or more alkaline earth metal oxides selected in amounts not exceeding the indicated proportions from the group consisting of up to 70% BaO, up to 60% SrO, up to 40% CaO, and up to 25% MgO, up to 35% total of R.sub.2 O, wherein R.sub.2 O consists of one or more alkali metal oxides selected in amounts not exceeding the indicated proportion from the group consisting of up to 35% Na.sub.2 O, up to 30% K.sub.2 O, and up to 15% Li.sub.2 O, up to 25% total of metal oxides selected from the group consisting of ZnO and MnO, up to 30% of SiO.sub.2, and up to 10% F.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: October 6, 1992
    Assignee: Corning Incorporated
    Inventors: Ronald L. Andrus, John F. MacDowell
  • Patent number: 5112777
    Abstract: This invention is particularly directed to the production of glass-ceramics specifically designed for bonding hard refractory particulate ceramics into dense, mechanically strong composite bodies. The inventive glass-ceramics are crystallized in situ from divalent metal borate glasses. The invention is particularly drawn to composite articles where Al.sub.2 O.sub.3 particles comprise the hard refractory ceramic and the inventive glasses react therewith to form an exceptionally strong bond therebetween accompanied with the development of divalent metal aluminoborate crystals.
    Type: Grant
    Filed: January 9, 1991
    Date of Patent: May 12, 1992
    Assignee: Corning Incorporated
    Inventor: John F. MacDowell
  • Patent number: 5023207
    Abstract: The present invention is directed to the preparation of glass-ceramic articles exhibiting an apparent annealing point of at least 1200.degree. C. and containing slawsonite crystallization consisting essentially, in weight percent, of 10-54% SrO, 10-40% Al.sub.2 O.sub.3, 36-55% SiO.sub.2, and up to 25% total of at least one alkaline earth metal oxide in the indicated proportion of 0-10% MgO, 0-15% CaO, and 0-20% BaO.
    Type: Grant
    Filed: March 12, 1990
    Date of Patent: June 11, 1991
    Assignee: Corning Incorporated
    Inventor: John F. MacDowell
  • Patent number: 4897509
    Abstract: This invention relates to the production of glass-ceramic materials particularly suitable for use as substrates in integrated circuit packaging. The inventive glass-ceramics can be prepared from thermally crystallizable glass capable of being concurrently sintered and crystallized in situ at temperatures between about 850.degree.-1000.degree. C. to bodies exhibiting dielectric constants less than about 6, linear coefficients of thermal expansion between about 12-60.times.10.sup.-7 /.degree.C. and containing cordierite solid solution as essentially the sole crystal phase. The glass-ceramics are essentially free from Li.sub.2 O and Na.sub.2 O and consist essentially, expressed in terms of weight percent on the oxide basis of 10-25% MgO+ZnO consisting of 2-18% MgO+0-21% ZnO, 20-38% Al.sub.2 O.sub.3, 40-52% SiO.sub.2, and 2-15% total of at least one oxide in the indicated proportion selected from the group consisting of up to 8% of an alkali metal oxide selected from the group consisting of K.sub.2 O, Rb.sub.
    Type: Grant
    Filed: August 31, 1988
    Date of Patent: January 30, 1990
    Assignee: Corning Incorporated
    Inventors: Louis M. Holleran, John F. MacDowell, Francis W. Martin
  • Patent number: 4861734
    Abstract: This invention is directed to the production of glass-ceramic bodies through the sintering of finely-divided glass powders into an integral body accompanied with the generation of crystals therein. The inventive products have compositions consisting essentially, selected from the group, in weight percent, consisting of:(a) 20-30% CaO, 35-55% Al.sub.2 O.sub.3, and 20-40% B.sub.2 O.sub.3 ;(b) 30-45% SrO, 30-45% Al.sub.2 O.sub.3, and 20-35% B.sub.2 O.sub.3 ;(c) 40-55% BaO, 25-40% Al.sub.2 O.sub.3, and 15-30% B.sub.2 O.sub.3 ; and(d) mixtures thereof.The predominant crystal phase is an alkaline earth metal aluminoborate.
    Type: Grant
    Filed: August 1, 1988
    Date of Patent: August 29, 1989
    Assignee: Corning Incorporated
    Inventor: John F. MacDowell
  • Patent number: 4833104
    Abstract: This invention is directed to the preparation of glass-ceramic materials especially suitable for use in multilayer substrates for integrated circuit packages. The inventive glass-ceramics are derived from thermally crystallizable glass which, in the form of frit, are capable of being sintered into an integral body at temperatures below 1000.degree. C. and essentially concurrently crystallized in situ to yield BPO.sub.4 as the predominant crystal phase. The inventive glass-ceramics exhibit a linear coefficient of thermal expansion between about 30-45.times.10.sup.-7 /.degree.C., a dielectric constant less than 5, and consist essentially, in weight percent, of 10-25% B.sub.2 O.sub.3, 20-40% P.sub.2 O.sub.5, and >50-65% SiO.sub.2.
    Type: Grant
    Filed: November 27, 1987
    Date of Patent: May 23, 1989
    Assignee: Corning Glass Works
    Inventors: John F. MacDowell, Robert J. Paisley
  • Patent number: 4666867
    Abstract: The present invention is concerned with the preparation of glass microfoams and gas-ceramics having compositions selected from the systems of SiO.sub.2 --Al.sub.2 O.sub.3 --B.sub.2 O.sub.3 --RO--R.sub.2 O, SiO.sub.2 --Al.sub.2 O.sub.3 (B.sub.2 O.sub.3)--P.sub.2 O.sub.5 --Li.sub.2 O--[ZrO.sub.2 (TiO.sub.2)], and SiO.sub.2 --P.sub.2 O.sub.5 --B.sub.2 O.sub.3 --[RO], wherein RO is selected from the group of MgO, CaO, SrO, BaO, and ZnO, and R.sub.2 O is selected from the group of alkali metal oxides. The foams comprise hydrogen-containing cells produced through the inclusion in the batch of a hydrogen-generating agent selected from the group of ammonium salts and/or a combination of amines and/or carbohydrates and/or hydrocarbons with phosphates.
    Type: Grant
    Filed: August 18, 1986
    Date of Patent: May 19, 1987
    Assignee: Corning Glass Works
    Inventors: George H. Beall, John F. MacDowell
  • Patent number: 4605443
    Abstract: This invention relates to the preparation of hydraulic cements consisting essentially of glasses having compositions within area ABCDEA of FIG. 1 which, when contacted with water, hydrate to form strong, low porosity cements having crystals composed predominantly of hydrogarnet solid solution and/or hydrogehlenite.
    Type: Grant
    Filed: January 28, 1985
    Date of Patent: August 12, 1986
    Assignee: Corning Glass Works
    Inventor: John F. MacDowell
  • Patent number: 4576920
    Abstract: This invention is directed to the production of transparent, translucent, or opaque glass-ceramic articles containing BPO.sub.4 as the predominant crystal phase by heat treating precursor glass articles consisting essentially, expressed in terms of weight percent on the oxide basis, of about:SiO.sub.2 : 10-50B.sub.2 O.sub.3 : 5-35P.sub.2 O.sub.5 : 25-75SiO.sub.2 +P.sub.2 O.sub.5 +B.sub.2 O.sub.3 : >90.
    Type: Grant
    Filed: May 23, 1985
    Date of Patent: March 18, 1986
    Assignee: Corning Glass Works
    Inventor: John F. MacDowell
  • Patent number: 4519828
    Abstract: This invention is concerned with the production of substantially transparent glass-ceramic articles containing mullite as the predominant crystal phase which can be prepared by crystallizing in situ precursor glasses capable of being melted at temperatures no higher than 1650.degree. C. The inventive articles consist essentially, in weight percent, of 10-70% SiO.sub.2, 7-40% B.sub.2 O.sub.3, 14-50% Al.sub.2 O.sub.3, 0-35% RO, wherein RO consists of at least one member of the group in the indicated proportions of 0-15% MgO, 0-20% CaO, 0-30% SrO, 0-30% BaO, and 0-30% PbO, and 0-30% R.sub.2 O, wherein R.sub.2 O consists of at least one member of the group in the indicated proportions of 0-10% Li.sub.2 O, 0-15% Na.sub.2 O, 0-25% K.sub.2 O, 0-25% Rb.sub.2 O, and 0-25% Cs.sub.2 O, the mole ratio Al.sub.2 O.sub.3 :RO+R.sub.2 O>1.3. Where 0.01-1% Cr.sub.2 O.sub.
    Type: Grant
    Filed: March 28, 1983
    Date of Patent: May 28, 1985
    Assignee: Corning Glass Works
    Inventors: George H. Beall, John F. MacDowell, Mark P. Taylor
  • Patent number: 4396720
    Abstract: This invention is concerned with the production of substantially transparent glass-ceramic articles containing mullite as the predominant crystal phase which can be prepared by crystallizing in situ precursor glasses capable of being melted at temperatures no higher than 1650.degree. C. The inventive articles consist essentially, in weight percent, of 1070% SiO.sub.2, 7-40% B.sub.2 O.sub.3, 14-50% Al.sub.2 O.sub.3, 0-35% RO, wherein RO consists of at least one member of the group in the indicated proportions of 015% MgO, 0-20% CaO, 0-30% SrO, 0-30% BaO, and 0-30% PbO, and 0-30% R.sub.2 O, wherein R.sub.2 O consists of at least one member of the group in the indicated proportions of 0-10% Li.sub.2 O, 0-15% Na.sub.2 O, 0-25% K.sub.2 O, 0-25% Rb.sub.2 O, and 0-25% Cs.sub.2 O, the mole ratio Al.sub.2 O.sub.3 :RO+R.sub.2 O>1.3. Where 0.01-1% Cr.sub.2 O.sub.
    Type: Grant
    Filed: July 6, 1982
    Date of Patent: August 2, 1983
    Assignee: Corning Glass Works
    Inventors: George H. Beall, John F. MacDowell, Mark P. Taylor
  • Patent number: 4341872
    Abstract: There are disclosed glass-ceramic materials characterized by a nepheline crystal phase and optionally having a secondary celsian or hexacelsian crystal phase. In addition to the SiO.sub.2, Al.sub.2 O.sub.3, Na.sub.2 O, and TiO.sub.2 as a nucleating agent, the materials contain K.sub.2 O and/or Li.sub.2 O in limited amount, and preferably also contain BaO. These additives provide microwave compatibility, a thermal coefficient of expansion below 95.times.10.sup.-7 /.degree.C., and suitability for application as glazed table or ovenware.
    Type: Grant
    Filed: June 5, 1981
    Date of Patent: July 27, 1982
    Assignee: Corning Glass Works
    Inventor: John F. MacDowell
  • Patent number: 4341835
    Abstract: Composite materials consisting of a matrix incorporating high-aspect-ratio reinforcement members, wherein the reinforcement members consist of relatively large, prestressed glass or glass-ceramic members, such as macrofilaments or rods having diameters in excess of about 0.010 inches, are described.
    Type: Grant
    Filed: January 26, 1981
    Date of Patent: July 27, 1982
    Assignee: Corning Glass Works
    Inventor: John F. MacDowell
  • Patent number: 4042362
    Abstract: The instant invention is concerned with a unique method for crystallizing glass bodies into glass-ceramic articles. More particularly, this invention is drawn to a method whereby glass-ceramic articles can be formed without cooling the precursor glass below the transformation range thereof. Thus, the glass melt is cooled and formed into a vitreous body. This vitreous body is cooled to a temperature no lower than about 25.degree.-250.degree. C. above the transformation range where nucleation is developed therewithin. Essentially immediately thereafter, the nucleated body is exposed to a temperature between about 100.degree.-500.degree. C. higher than that of the nucleation step to cause the growth of crystals on the nuclei. The process significantly expedites the production of glass-ceramic articles and substantially reduces energy consumption from the forming stage to the finished product.
    Type: Grant
    Filed: May 18, 1976
    Date of Patent: August 16, 1977
    Assignee: Corning Glass Works
    Inventors: John F. MacDowell, Hermann L. Rittler