Plastic and nonmetallic article shaping or treating: processes – Including step of generating heat by friction
Patent
1993-10-08
1995-09-05
Simmons, David A.
Plastic and nonmetallic article shaping or treating: processes
Including step of generating heat by friction
264 65, 264 66, 148284, 148285, 148286, 4273722, 4273763, 4273835, 156 89, C04B 3500, B22F 700
Patent
active
054472911
ABSTRACT:
Shaped refractory ceramic and refractory ceramic composite objects are made from corresponding shaped, oxidation-resistant-metal-bearing objects through exposure to an oxidizing environment without substantial changes in dimensions by providing in the shaped metal-bearing objects a combination of a) metals which when oxidized form a ceramic compound with a larger molar volume than the molar volume of the metals consumed to make the ceramic compound with b) metals which when oxidized form a ceramic compound with a smaller molar volume than the molar volume of the metals consumed to make the ceramic compound. Metal-bearing objects, containing metals such as silicon or aluminum, which when oxidized form ceramic or ceramic-composite objects containing refractory ceramic compounds of desired properties, such as compounds containing silicon oxide or aluminum oxide, for which the ceramic compounds have a molar volume that is greater than the molar volumes of the metals consumed to make the ceramic compounds, expand upon oxidation, thereby having an adverse effect on the properties of the resulting ceramic and preventing the maintenance of the dimensions of the metal-bearing objects. The present invention is the discovery that when alkali or alkaline earth metals, which when oxidized have molar volumes that are less than such metals, are alloyed with or otherwise combined with oxidation-resistant metals that are formed into the metal-bearing objects and converted into desired refractory ceramics, swelling, resulting loss of mechanical properties, and dimensional changes are reduced or eliminated. Further, such combination of a) metals that after oxidation form ceramic compounds having a molar volume greater than the molar volumes of the metals consumed to make the ceramic compound with b) alkali or alkaline earth metals that after oxidation form ceramic compounds having a molar volume less than the molar volume of the alkali or alkaline earth metals consumed to make the ceramic compounds provides an unexpectedly advantageous brazing alloy for joining ceramic-bearing bodies.
REFERENCES:
patent: 2167701 (1939-08-01), Whitfield et al.
patent: 3255027 (1966-06-01), Talsma
patent: 3473938 (1969-10-01), Oberlin
patent: 3473987 (1969-10-01), Sowards
patent: 3730783 (1973-05-01), Streel
patent: 3907611 (1975-09-01), Sasame et al.
patent: 4102678 (1978-07-01), Gothard et al.
patent: 4364780 (1982-12-01), Blanken
patent: 4452674 (1984-06-01), Gillich et al.
patent: 4480677 (1984-11-01), Henson et al.
patent: 4557770 (1985-12-01), Vidoz et al.
patent: 4627959 (1986-12-01), Gilman et al.
patent: 4645117 (1987-02-01), Knapp et al.
patent: 4713360 (1987-12-01), Newkirk
patent: 4735771 (1988-04-01), Corwin
patent: 4761266 (1988-08-01), Bruski
patent: 4808558 (1989-02-01), Park et al.
patent: 4850422 (1989-07-01), Compton et al.
patent: 4871696 (1989-10-01), Newkirk et al.
patent: 4946806 (1990-08-01), Willard
patent: 5120352 (1992-06-01), Jackson et al.
patent: 5120580 (1992-06-01), Lesher et al.
patent: 5214011 (1993-05-01), Breslin
G. J. Yurek et al., "Direct Synthesis of a Metal/Superconducting Oxide Composite by Oxidation of a Metallic Precursor", J. Electrochem. Soc., vol. 134, 1987, pp. 2635-2636.
Z. A. Munir, "Synthesis of High Temperture Materials of Self-Propagating Combustion Methods", Amer. Cer. Soc. Bull., vol. 67, No. 2, 1988, pp. 342-349.
M. S. Newkirk et al., "Preparation of Lanixide.TM. Ceramic Matrix Composites: Matrix Formation by the Directed Oxidation of Molten Metals", Ceram. Eng. Sci. Proc., vol. 8, No. 7-8, 1987, pp. 879-882.
J. D. Cawley, "Joining of Ceramic-Matrix Composites", Amer. Cer. Soc. Bull., vol. 68, No. 9, 1989, pp. 1619-1623.
A. S. Nagelberg et al., "Formation of Al.sub.2 O.sub.3 /Metal Composites by the Directed Oxidation of Molten Aluminum-Magnesium-Silicon Alloys: Part II, Growth Kinetics", J. Am. Ceram. Soc., vol. 75, No. 2, 1992, pp. 455-462.
S. Antolin et al., "Formation of Al.sub.2 O.sub.3 /Metal Composites by the Direction Oxidation of Molten Aluminum-Magnesium-Silicon Alloys: Part I, Mictrostructural Development", J. Am. Ceram. Soc., vol. 75, No. 2, 1992, pp. 447-454.
Foster Frank H.
Mayes M. Curtis
Simmons David A.
The Ohio State University
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