ALUMINUM ALLOY CASTING AND METHOD FOR PRODUCING THE SAME, AND APPARATUS FOR PRODUCING SLIDE MEMBER

1 . An aluminum alloy casting obtained by cooling a melt of an aluminum alloy containing iron, wherein

a metal structure of at least one surface in the aluminum alloy casting contains the iron in the state of a grain of pure iron or an iron-based intermetallic compound with another metal, and

the metal structure further contains a eutectic silicon having a greatest diameter of 10 μm or less in a two-dimensional surface.

2 . An aluminum alloy casting according to claim 1 , wherein the aluminum alloy casting is a sleeve having an inner wall and an outer wall, and the inner wall has the one surface.

3 . A method for producing an aluminum alloy casting, comprising the steps of:

pouring a melt of an aluminum alloy containing iron into a vessel,

vibrating the melt in a completely liquid state using a vibrator at a frequency of 20 to 1000 Hz until the melt is cooled to a solidification point of the melt,

stopping vibrating the melt when the melt is cooled to the solidification point, and

further cooling the melt at a cooling rate higher than that down to the solidification point, thereby solidifying the melt to obtain an aluminum alloy casting, wherein

a metal structure of at least one surface in the aluminum alloy casting contains the iron in the state of a grain of pure iron or an iron-based intermetallic compound with another metal, and

the metal structure further contains a eutectic silicon having a greatest diameter of 10 μm or less in a two-dimensional surface.

4 . A method according to claim 3 , wherein when the melt is cooled to a solidification starting point, a core having a temperature lower than that of the melt is inserted into the melt, whereby the cooling rate is increased and a cavity corresponding to the shape of the core is formed in the aluminum alloy casting.

5 . A method according to claim 4 , wherein in the melt, a portion in contact with the core is cooled at a cooling rate of 30° C./second or more, and a portion farthest from the core is cooled at a cooling rate of 10° C./second or less.

6 . A method according to claim 4 , wherein the aluminum alloy casting is a sleeve having an inner wall and an outer wall, and the inner wall has the one surface.

7 . An apparatus for producing a slide member, comprising

a vessel for storing a metal melt containing at least a base metal and a hard metal harder than the base metal,

a vibration applying means for vibrating the metal melt in the vessel at a frequency of 1000 Hz or less, and

a core that is inserted into the metal melt vibrated by the vibration applying means to cool the metal melt.

8 . An apparatus according to claim 7 , wherein the base metal is aluminum, and the hard metal contains iron.

9 . An apparatus according to claim 7 , wherein the vibration applying means contains a vibration generator and a vibrator,

the vibration generator has a rotor and an eccentric integrally rotatable with the rotor in an eccentric state with respect to a rotation axis of the rotor, and

the vibrator is connected to the vibration generator, extends in a direction of the rotation axis of the rotor, and is inserted into the metal melt.

10 . An apparatus according to claim 9 , further comprising

a stage on which the vessel is placed,

a conveying means for transferring the vessel placed on the stage to a first position and a second position, and

an elevating means for raising and lowering the stage,

wherein

the vibrator is disposed at a position corresponding to the stage in the first position, and

the core is disposed at a position corresponding to the stage in the second position.

11 . An apparatus according to claim 7 , wherein the vessel comprises a heat insulation material.