Method to increase local cooling rate and improve material properties in a low-pressure sand-casting head
AssigneeGM Global Technology Operations LLC
InventorsLiang Wang, Qigui Wang, Dale A. Gerard, Steven L. Burkholder, Ronald C. Daul
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Abstract
A low-pressure sand-casting system includes a sand-casting mold receiving a molten casting material to cast an automobile vehicle cylinder head. A port is created in the automobile vehicle cylinder head. A manifold port metal core assembly includes a metal core. A compressible material coating is applied on the manifold port core metal core.
Claims20
A low-pressure sand-casting system, comprising:
- a sand-casting mold receiving a molten casting material to cast an automobile vehicle cylinder head;
- a port created in the automobile vehicle cylinder head;
- a manifold port metal core assembly having a metal core;
- and
- a compressible material coating applied on the manifold port core metal core.
The method of claim 11, wherein the compressible material coating is applied onto the metal core by spray coating, printing or dipping at least proximate to an end face of the metal core at a first end of the metal core.
The method of claim 11, wherein a body of the metal core has a tapering shape continuously reducing in cross sectional area from a first end having a first cross sectional area toward a second end having a second cross sectional area smaller than the first cross sectional area.
A method for low-pressure sand-casting a cylinder head of an automobile vehicle engine, comprising:
- creating a port in an automobile engine cast cylinder head low pressure sand-casting mold;
- applying a compressible material coating having graphite and carbon fiber on a metal core of a manifold port metal core assembly;
- predetermining an initial thickness (t) of the compressible material coating at least equal to a compression amount of the compressible material coating anticipated due to shrinkage of a casting material located proximate to the port and surrounding the compressible material coating as the casting material cools;
- and
- inserting the manifold port metal core assembly into the port prior to filling the cylinder head sand-casting mold with the casting material.
A method to locally increase cooling during casting of an automobile vehicle cylinder head, comprising:
- creating a port in an automobile engine cast cylinder head low pressure sand-casting mold;
- applying a compressible material coating on a metal core of a manifold port metal core assembly;
- selecting a material of the compressible material coating exhibiting an increasing thermal conductivity during compression of the compressible material coating;
- and
- inserting the manifold port metal core assembly into the port and filling the cylinder head sand-casting mold with a casting material.
Dependencies are inferred from the claim text.