High-strength metal-matrix composite and method for producing high-strength metal-matrix composite

A method for producing a high-strength metal matrix composite, the method comprising:

• providing a porous filled body or molded body (preform) using a mixed powder obtained by adding at least one aluminum or aluminum alloy powder selected from the group consisting of an aluminum powder and an aluminum alloy powder each having an average particle size of 10 μm or larger and 300 μm or smaller to at least one fine powder selected from the group consisting of a metal powder and a ceramic powder each having an average particle size of 0.3 μm or larger and 8 μm or smaller;
• and
• impregnating and filling the resulting filled body or molded body (preform) with molten aluminum or a molten aluminum alloy at a high pressure as high as a pressure of 20 MPa or higher and 200 MPa or lower to form a composite, thereby providing a metal matrix composite having a fine powder-filling rate of 10% by volume or more and 50% by volume or less and a flexural strength of 500 MPa or higher and 800 MPa or lower.

A method for producing a high-strength metal matrix composite, the method comprising:

• providing a porous filled body or molded body (preform) using a Mg powder-containing mixed powder obtained in such a way that a mixed powder is obtained by adding at least one aluminum or aluminum alloy powder selected from the group consisting of an aluminum powder and an aluminum alloy powder each having an average particle size of 10 μm or larger and 300 μm or smaller to at least one fine powder selected from the group consisting of a metal powder and a ceramic powder each having an average particle size of 0.3 μm or larger and 8 μm or smaller, and further a magnesium powder within a range of 0.5 parts by mass or more and 10 parts by mass or less is added to 100 parts by mass of the mixed powder;
• and
• impregnating and filling the resulting filled body or molded body (preform) with molten aluminum or a molten aluminum alloy without pressurization to form a composite, thereby providing a metal matrix composite having a fine powder-filling rate of 10% by volume or more and 50% by volume or less and a flexural strength of 500 MPa or higher and 800 MPa or lower.