The present disclosure discloses a high-strength and high-thermal conductivity new material composite brake drum and a preparation method thereof. The composite brake drum is composed of an outer layer of high-strength ductile iron and an inner layer of high-thermal conductivity gray cast iron, which are integrated by centrifugal compound casting. The outer layer of the composite brake drum is firstly poured on the production line of iron particle-filled coated sand shells. Due to the fast solidification and cooling of the iron particle-filled coated sand shells, the castings have the characteristics of fine and dense organization structures to ensure the high strength and high toughness of the ductile iron of the outer layer. On this basis, the inner gray cast iron is poured under centrifugal casting conditions, in which a good metallurgical bond between the inner and outer layers is achieved by controlling the centrifugal casting process.

The present disclosure discloses a high-strength and high-thermal conductivity new material composite brake drum and a preparation method thereof. The composite brake drum is composed of an outer layer of high-strength ductile iron and an inner layer of high-thermal conductivity gray cast iron, which are integrated by centrifugal compound casting. The outer layer of the composite brake drum is firstly poured on the production line of iron particle-filled coated sand shells. Due to the fast solidification and cooling of the iron particle-filled coated sand shells, the castings have the characteristics of fine and dense organization structures to ensure the high strength and high toughness of the ductile iron of the outer layer. On this basis, the inner gray cast iron is poured under centrifugal casting conditions, in which a good metallurgical bond between the inner and outer layers is achieved by controlling the centrifugal casting process.

Systems and methods may utilize magnetic rotors to heat molten metal in the corner regions of a mold during casting (e.g., casting of an ingot, billet, or slab). The magnetic rotors are positioned adjacent to the corners of the mold and heat the molten metal in the corner region to increase the temperature of the molten metal adjacent the corners. The increased temperature of the molten metal in the mold corners can prevent intermetallics from forming in the molten metal or otherwise reduce such formation.

Systems and methods may utilize magnetic rotors to heat molten metal in the corner regions of a mold during casting (e.g., casting of an ingot, billet, or slab). The magnetic rotors are positioned adjacent to the corners of the mold and heat the molten metal in the corner region to increase the temperature of the molten metal adjacent the corners. The increased temperature of the molten metal in the mold corners can prevent intermetallics from forming in the molten metal or otherwise reduce such formation.

A pump system for a metal furnace includes a tank and a magnetic stirrer. The tank includes a tank chamber that is configured to receive a fluid, such as a molten material. The tank is positioned above magnetic stirrer and such that the magnetic stirrer is outside of the tank chamber. The magnetic stirrer includes a rotating permanent magnet configured to generate a moving magnetic field in the molten material in the tank chamber that induces movement in the molten material.

A pump system for a metal furnace includes a tank and a magnetic stirrer. The tank includes a tank chamber that is configured to receive a fluid, such as a molten material. The tank is positioned above magnetic stirrer and such that the magnetic stirrer is outside of the tank chamber. The magnetic stirrer includes a rotating permanent magnet configured to generate a moving magnetic field in the molten material in the tank chamber that induces movement in the molten material.

Proposed is an electromagnetic vibration stirring device of semi-solid high pressure casting equipment. The electromagnetic vibration stirring device includes: a ring-shaped casing including an inner wall into which a sleeve is inserted and an outer wall spaced apart from the inner wall; and a magnetic field generating unit located between the inner wall and the outer wall of the casing, and including a plurality of electromagnets radially arranged at equal intervals around the sleeve in a circumferential direction of the sleeve, each of the electromagnets including a core and a coil surrounding the core. The magnetic field generating unit generates a magnetic field by applying a current to the electromagnets in a clockwise or counterclockwise direction, and each portion of a semi-solid molten metal is sequentially vibrated by the magnetic field along the circumferential direction of the sleeve, thereby controlling a microstructure of the molten metal.

Proposed is an electromagnetic vibration stirring device of semi-solid high pressure casting equipment. The electromagnetic vibration stirring device includes: a ring-shaped casing including an inner wall into which a sleeve is inserted and an outer wall spaced apart from the inner wall; and a magnetic field generating unit located between the inner wall and the outer wall of the casing, and including a plurality of electromagnets radially arranged at equal intervals around the sleeve in a circumferential direction of the sleeve, each of the electromagnets including a core and a coil surrounding the core. The magnetic field generating unit generates a magnetic field by applying a current to the electromagnets in a clockwise or counterclockwise direction, and each portion of a semi-solid molten metal is sequentially vibrated by the magnetic field along the circumferential direction of the sleeve, thereby controlling a microstructure of the molten metal.

A method for making an equiaxed investment casting. The method utilizes an ultrasonic generator to send an ultrasonic pulse into molten metal in an investment casting mold. The investment casting mold is positioned within a working zone of furnace having low output induction coils for generating a convection current in molten metal. The ultrasonic pulse separates dendrites growing from the face of the mold inward into the molten metal. Instead, equiaxed grains can nucleate within the molten metal. In addition, the ultrasonic pulse and the low output induction coils circulate the molten metal as solute is rejected from solidifying equiaxed grains. The mixing reduces the effects of segregation in the solidifying alloy and assists in nucleating equiaxed grains.

A method for making an equiaxed investment casting. The method utilizes an ultrasonic generator to send an ultrasonic pulse into molten metal in an investment casting mold. The investment casting mold is positioned within a working zone of furnace having low output induction coils for generating a convection current in molten metal. The ultrasonic pulse separates dendrites growing from the face of the mold inward into the molten metal. Instead, equiaxed grains can nucleate within the molten metal. In addition, the ultrasonic pulse and the low output induction coils circulate the molten metal as solute is rejected from solidifying equiaxed grains. The mixing reduces the effects of segregation in the solidifying alloy and assists in nucleating equiaxed grains.