Powder metallurgy processes – Powder metallurgy processes with heating or sintering – Metal and nonmetal in final product
Patent
1995-02-03
1998-12-08
Jordan, Charles T.
Powder metallurgy processes
Powder metallurgy processes with heating or sintering
Metal and nonmetal in final product
419 45, 419 46, 419 47, B22F 326
Patent
active
058483497
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to modifying the properties of a metal matrix composite body by a post formation process treatment and/or a substantially contiguous modification treatment. The post formation process treatment and the substantially contiguous modification treatment may be applicable to a variety of metal matrix composite bodies produced by various techniques, and is particularly applicable to modifying the properties of a metal matrix composite body produced by a spontaneous infiltration technique. Particularly, in any metal matrix composite formation process at least a portion of the matrix metal of the metal matrix composite body and/or the filler material of the metal matrix composite body is modified or altered during and/or after the formation process.
BACKGROUND ART
Composite products comprising a metal matrix and a strengthening or reinforcing phase such as ceramic particulates, whiskers, fibers or the like, show great promise for a variety of applications because they combine some of the stiffness and wear resistance of the reinforcing phase with the ductility and toughness of the metal matrix. Generally, a metal matrix composite will show an improvement in such properties as strength, stiffness, contact wear resistance, and elevated temperature strength retention relative to the matrix metal in monolithic form, but the degree to which any given property may be improved depends largely on the specific constituents, their volume or weight fraction, and how they are processed in forming the composite. In some instances, the composite also may be less dense than the matrix metal per se. Aluminum matrix composites reinforced with ceramics such as silicon carbide in particulate, platelet, or whisker form, for example, are of interest because of their higher stiffness, wear resistance and high temperature strength relative to aluminum.
Various metallurgical processes have been described for the fabrication of aluminum matrix composites, including methods based on powder metallurgy techniques and liquid-metal infiltration techniques which make use of pressure casting, vacuum casting, stirring, and wetting agents. With powder metallurgy techniques, the metal in the form of a powder and the reinforcing material in the form of a powder, whiskers, chopped fibers, etc., are admixed and then either cold-pressed and sintered, or hot-pressed. The maximum ceramic volume fraction in silicon carbide reinforced aluminum matrix composites produced by this method has been reported to be about 25 volume percent in the case of whiskers, and about 40 volume percent in the case of particulates.
The production of metal matrix composites by powder metallurgy techniques utilizing conventional processes imposes certain limitations with respect to the characteristics of the products attainable. The volume fraction of the ceramic phase in the composite is limited typically, in the case of particulates, to about 40 percent. Also, the pressing operation poses a limit on the practical size attainable. Only relatively simple product shapes are possible without subsequent processing (e.g., forming or machining) or without resorting to complex presses. Also, nonuniform shrinkage during sintering can occur, as well as nonuniformity of microstructure due to segregation in the compacts and grain growth.
U.S. Pat. No. 3,970,136, granted Jul. 20, 1976, to J. C. Cannell et al., describes a process for forming a metal matrix composite incorporating a fibrous reinforcement, e.g. silicon carbide or alumina whiskers, having a predetermined pattern of fiber orientation. The composite is made by placing parallel mats or felts of coplanar fibers in a mold with a reservoir of molten matrix metal, e.g., aluminum, between at least some of the mats, and applying pressure to force molten metal to penetrate the mats and surround the oriented fibers. Molten metal may be poured onto the stack of mats while being forced under pressure to flow between the mats. Loadings of up to about 50% by volume of reinforcing fibers in
REFERENCES:
patent: 918069 (1909-04-01), Marius
patent: 3031340 (1962-04-01), Girardot
patent: 3149409 (1964-09-01), Maruhn
patent: 3364976 (1968-01-01), Reding et al.
patent: 3396777 (1968-08-01), Reding, Jr.
patent: 3718441 (1973-02-01), Landingham
patent: 3864154 (1975-02-01), Gazza et al.
patent: 3868267 (1975-02-01), Gazza et al.
patent: 3915699 (1975-10-01), Umehara et al.
patent: 3969553 (1976-07-01), Kondo et al.
patent: 3970136 (1976-07-01), Cannell et al.
patent: 4082864 (1978-04-01), Kendall et al.
patent: 4232091 (1980-11-01), Grimshaw et al.
patent: 4254621 (1981-03-01), Nagumo
patent: 4341823 (1982-07-01), Sexton et al.
patent: 4376803 (1983-03-01), Katzman
patent: 4376804 (1983-03-01), Katzman
patent: 4450207 (1984-05-01), Donomoto et al.
patent: 4473103 (1984-09-01), Kenney et al.
patent: 4605440 (1986-08-01), Halverson et al.
patent: 4630665 (1986-12-01), Novak, Jr. et al.
patent: 4657065 (1987-04-01), Wada et al.
patent: 4662429 (1987-05-01), Wada et al.
patent: 4673435 (1987-06-01), Yamaguchi et al.
patent: 4702770 (1987-10-01), Pyzik et al.
patent: 4713111 (1987-12-01), Cameron et al.
patent: 4718941 (1988-01-01), Halverson et al.
patent: 4731298 (1988-03-01), Shindo et al.
patent: 4753690 (1988-06-01), Wada et al.
patent: 4777014 (1988-10-01), Newkirk et al.
patent: 4777097 (1988-10-01), Kubo et al.
patent: 4802524 (1989-02-01), Donomoto
patent: 4806508 (1989-02-01), Dwivedi
patent: 4808558 (1989-02-01), Park
patent: 4818734 (1989-04-01), Kantner et al.
patent: 4828008 (1989-05-01), White et al.
patent: 4834938 (1989-05-01), Pyzik et al.
patent: 4851375 (1989-07-01), Newkirk et al.
patent: 4871008 (1989-10-01), Dwivedi et al.
patent: 4885130 (1989-12-01), Claar et al.
patent: 4885131 (1989-12-01), Newkirk
patent: 4915902 (1990-04-01), Brupbacher et al.
patent: 4915903 (1990-04-01), Brupbacher et al.
patent: 4915908 (1990-04-01), Nagle et al.
patent: 4916029 (1990-04-01), Nagle et al.
patent: 4956137 (1990-09-01), Dwivedi
patent: 4981632 (1991-01-01), Claar et al.
patent: 5296417 (1994-03-01), Claar et al.
patent: 5298283 (1994-03-01), Rocazella et al.
patent: 5301738 (1994-04-01), Newkirk et al.
patent: 5316069 (1994-05-01), Aghajanian et al.
patent: 5329984 (1994-07-01), Newkirk et al.
X. S. Ning, T. Okamoto, Y. Miyamoto, A. Koreeda and K. Suganuma, "Reaction Chemistry at Joined Interfaces Between Silicon Nitride and Aluminum", The Institute of Scientific and Industrial Research, Journal of Materials Science, vol. 26 (1991), pp. 4142-4149.
F. Delannay, L. Froyen, and A. Deruyttere, "Review: The Wetting of Solids by Molten Metals and Its Relation to the Preparation of Metal-Matrix Composites", Journal of Materials Science, vol. 22, No. 1, pp. 1-16, Jan. 1987.
G. R. Edwards and D. L. Olson, "The Infiltration Kinetics of Aluminum in Silicon Carbide Compacts", Annual Report from Center for Welding Research, Colorado School of Mines, under ONR Contract No. M00014-85-K-0451, DTIC Report AD-A184 682, Jul. 1987.
A. Mortensen, J. A. Cornie, and M. C. Flemings, "Solidification Processing of Metal-Matrix Composities", Journal of Metals, vol. 40, No. 2, pp. 12-19, Feb. 1988.
A. Mortensen, M. N. Gungor, J. A. Cornie, and M. C. Flemings "Alloy Microstructures in Cast Metal Matrix Composites", Journal of Metals, vol. 38, No. 3, pp. 30-35, Mar. 1986.
B. D. Sparks and F. W. Meadus, "The Development of an Infiltrated Lead/Iron Composite Materials for Use as a Non-toxic Bird Shot", Composites, pp. 37-39, Jan. 1978.
Aghajanian Michael Kevork
Mortenson Mark Gordon
Nagelberg Alan Scott
Newkirk Marc Stevens
Ravi Vilupanur Alwar
Jenkins Daniel
Jordan Charles T.
Lanxide Technology Company, LP
Ramberg Jeffrey R.
LandOfFree
Method of modifying the properties of a metal matrix composite 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 Method of modifying the properties of a metal matrix composite b, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of modifying the properties of a metal matrix composite b will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-189978