Compositions: ceramic – Ceramic compositions – Refractory
Patent
1990-07-16
1993-06-15
Bell, Mark L.
Compositions: ceramic
Ceramic compositions
Refractory
501132, 501153, 51309, C04B 3510
Patent
active
052198065
ABSTRACT:
This invention provides an improved alpha alumina-based ceramic and a method to make the same. The improvement consists of the addition of a chromium-based nucleating agent. Particularly useful embodiments of the improved alpha alumina-based ceramic include abrasive particles and fibers.
REFERENCES:
patent: B502773 (1976-01-01), Sowman
patent: 3108888 (1963-10-01), Bugosh
patent: 3491491 (1970-01-01), Ueltz
patent: 3491492 (1970-01-01), Ueltz
patent: 3615308 (1971-10-01), Amero
patent: 3717497 (1973-02-01), Stradley et al.
patent: 3808015 (1974-04-01), Seufert
patent: 3853688 (1974-12-01), D'Ambrosio
patent: 4007020 (1977-02-01), Church et al.
patent: 4019914 (1977-04-01), Esper et al.
patent: 4101615 (1978-07-01), Horikiri et al.
patent: 4125406 (1978-11-01), Sowman
patent: 4217113 (1980-08-01), Suh
patent: 4252544 (1981-12-01), Takahashi
patent: 4574003 (1986-03-01), Gerk
patent: 4623364 (1986-11-01), Cottringer et al.
patent: 4657754 (1987-04-01), Bauer
patent: 4744802 (1988-05-01), Schwabel
patent: 4770671 (1988-09-01), Monroe et al.
patent: 4797139 (1989-01-01), Bauer
patent: 4829031 (1989-05-01), Roy et al.
patent: 4881951 (1989-11-01), Wood et al.
patent: 4964883 (1990-10-01), Morris et al.
patent: 5009676 (1991-04-01), Rue et al.
"Enhanced Densification of Boehmite Sol-Gels by Alpha Alumina Seeding", Kumagai et al., Communications of the American Ceramic Society, Nov., 1984, C-230-31.
"Microstructural Evolution in Sintering of ALOOH Gels", Yarbrough et al., J. Mater. Res., 3, (4), 1987, pp. 494-515.
"Enhancing densification of 93% Al.sub.2 O.sub.3 -7% MgO triphasic xerogels with crystalline .alpha.-Al.sub.2 O.sub.3 and MgAl.sub.2 O.sub.4 seeds", Komarneni et al., J. Mater. Sci. Lett., 6, 1987, pp. 525-527.
"Sapphire Whiskers From Boehmite Gel Seeded With .alpha.-Alumina", Jagota et al, J. Cryst. Growth, 85, 1987, pp. 527-534.
"Ceramics by the Solution-Sol-Gel Route", Roy, Science, 238, Dec. 18, 1987, pp. 1664-1669.
"Solid-Phase Epitaxy of Boehmite-Derived .alpha.-Alumina on Hematite Seed Crystals", McArdle et al, J. Am. Ceramic Soc., 72, (5), 1989, pp. 864-867.
"Nucleation of alpha alumina in boehmite gel", Pach et al., J. Mater. Res., 5, (2), Feb. 2, 1990, pp. 278-285.
"Effects of Metallic Oxides on .alpha.-Transformation of Alumina", Wakao et al., Nagoya Kogyo Gijutsu Shikeusho Hokoko II, 11, (9), Sep. 1962, pp. 588-595.
"Influence of Cr and Fe on Formation of .alpha.-Al.sub.2 O.sub.3 from .gamma.-Al.sub.2 O.sub.3 ", J. Am. Ceram. Soc., 57, (8), 1974, pp. 367-371, (Bye et al.).
"The Effect of Cr.sup.'+ and Fe.sup.3+ Ions on the Transformation of Different Aluminum Hydroxides to .alpha.-Al.sub.2 O.sub.3 ", Tsuchida et al., Thermochim. Acta., 64, 1983, pp. 337-353.
"Transformation and Microstructure Control in Boehmite-derived Alumina by Ferric Oxide Seeding", Adv. Cer. Matls., 3, (4), 1988, pp. 387-392 (McArdle et al).
"Alpha Alumina Formation in Al.sub.2 O.sub.3 Gels", Dynys et al., Ultrastructure Processing of Ceramics, Glasses, and Composites, Ch. 11, Hench et al., ed., 1984.
"Lowering the Sintering Temperature and Enhancing Densification by Epitaxy in Structurally diphasic Al.sub.2 O.sub.3 and Al.sub.2 O.sub.3 -MgO Xerogels", Suwa et al., Matl. Sci. Eng., 83, 1986, pp. 151-159.
"Controlled Transformation and Sintering of a Boehmite Sol-Gel by .alpha.-Alumina Seeding", Kumagi et al., J. Am. Ceram. Soc., 68, (9), 1985, pp. 500-505.
"Low-Temperature Sintering of Aluminum Oxide", Yeh et al., J. Am. Ceram. Soc., 71, (10), 1988, pp. 841-844.
"Controlled Chemical Nucleation of Alpha Alumina Transformation", Messing et al., Science of Ceramics 14, Taylor, ed., 1988, pp. 101.sub.]106.
"Lowering Crystallization Temperatures by Seeding in Structurally Diphasic Al.sub.2 O.sub.3 -MgO Xerogels", Suwa et al., J. Am. Ceram. Soc., 68, (9), 1985, pp. C238-C240.
"Fine Particulates to Ultrafine-Grain Ceramics", Vasilos et al., Ultrafine-Grain Ceramics, Proc. of 15th Sagamore Army Mat. Res. Conf., Ch. 8, 1970, pp. 156-157 and 165-166.
"Study on Alumina as Raw Materials for Artificial Gems (Thermal Decomposition Process of Alums)", Okada et al., J. Ind. Chem., 59(11), 1956, pp. 1301 (71)-04 (74).
"Effect of Sintering Atmosphere on Densification of MgO-Doped Al.sub.2 O.sub.3 ", Paek et al J. Am. Ceram. Soc., 71, (8), 1988, pp. C-380-C-382.
"Nucleation and Epitaxial Growth In Diphasis (Crystalline & Amorphous) Gels", Roy et al, publication information unknown.
"A Novel Combustion Process For The Synthesis of Fine Particle .alpha.-Alumina and Related Oxide Materials", Mat. Lett., 6(11,12), Jul., 1988, pp. 427-432.
E. Ryshkewitch, Oxide Ceramic, Academic Press, New York, 1960, pp. 193-195.
Allen Gregory D.
Bell Mark L.
Griswold Gary L.
Kirn Walter N.
Minnesota Mining and Manufacturing Company
LandOfFree
Alpha phase seeding of transition alumina using chromium oxide-b does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Alpha phase seeding of transition alumina using chromium oxide-b, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Alpha phase seeding of transition alumina using chromium oxide-b will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1042527