Metal matrix composite and method of forming
First Claim
Patent Images
1. A method for producing a metal matrix composite comprising:
- stirring a reinforcement with an aluminum-containing molten or semisolid metal or alloy and between 0.005 and 10 wt. % calcium (Ca) to form a mixture, wherein the reinforcement is composed of particles each having a surface with a surface area bearing at least 20% of titanium oxide (TiO2), and the TiO2 is of crystal form other than anatase; and
cooling the mixture to produce a solid metal matrix composite to form a boundary material system between the crystals and the matrix, the boundary material system comprising calcium and aluminum oxides.
1 Assignment
0 Petitions
Accused Products
Abstract
Use of Ca in metal matrix composites (MMC) allows for incorporation of small and large amounts of ceramic (e.g. rutile TiO2) into the metal (Al, or its alloys). Calcium remains principally out of the matrix and is part of a boundary layer system that has advantages for integrity of the MMC. Between 0.005 and 10 wt. % calcium (Ca) may be included, and more than 50 wt. % of rutile has been shown to be integrated. Rutile may therefore be used to reduce melt loss due to calcium from an aluminum or aluminum alloy melt.
7 Citations
47 Claims
-
1. A method for producing a metal matrix composite comprising:
-
stirring a reinforcement with an aluminum-containing molten or semisolid metal or alloy and between 0.005 and 10 wt. % calcium (Ca) to form a mixture, wherein the reinforcement is composed of particles each having a surface with a surface area bearing at least 20% of titanium oxide (TiO2), and the TiO2 is of crystal form other than anatase; and cooling the mixture to produce a solid metal matrix composite to form a boundary material system between the crystals and the matrix, the boundary material system comprising calcium and aluminum oxides. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A metal matrix composite (MMC) comprising:
-
a metal matrix of an aluminum or an alloy of aluminum; and numerous sub-millimeter dimension embedded particles of a ceramic distributed throughout the metal matrix, the embedded particles comprising crystals of titanium oxide (TiO2) in crystal form other than anatase, wherein 0.005 to 10 wt. % calcium is present, and a boundary material system is formed between the crystals and the matrix, the boundary system comprising calcium and aluminum oxides. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26)
-
-
27. A method for reducing melt loss due to calcium defects in parts formed from an aluminum or aluminum alloy melt, the method comprising estimating a molar amount of calcium present, and adding at least an equal molar amount of rutile titania to the aluminum or aluminum alloy melt to form within the aluminum a boundary material system between crystals of the rutile titania and the aluminum, the boundary system comprising calcium and aluminum oxides.
-
28. A method for producing a metal matrix composite comprising:
-
at least partially melting an aluminum metal or alloy to form a molten or semisolid metal or alloy containing between 0.005 and 10 wt. % calcium (Ca); stirring into the metal or alloy a reinforcement composed of particles of titanium oxide (TiO2) of a crystal form other than anatase to form a mixture; and cooling the mixture to produce a solid metal matrix composite forming a boundary material system between the crystals and the matrix, the boundary material system comprising calcium and aluminum oxides. - View Dependent Claims (29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39)
-
-
40. A cast part comprising:
-
a metal matrix of an aluminum or an alloy of aluminum; and numerous sub-millimeter dimension embedded particles of a ceramic distributed throughout the metal matrix, the embedded particles comprising crystals of titanium oxide (TiO2) in crystal form other than anatase, wherein 0.005 to 10 wt. % calcium is present, and a boundary material system is formed between the crystals and the matrix, the boundary system comprising calcium and aluminum oxides. - View Dependent Claims (41, 42, 43, 44, 45, 46, 47)
-
Specification