An apparatus for countergravity casting a metallic material, has: a crucible for holding melted metallic material; a casting chamber for containing a mold; a fill tube capable of extending into the crucible to communicate melted metallic material to the casting chamber; and a gas source coupled to a headspace of the melting vessel to allow the gas source to pressurize the headspace to establish a pressure differential to force the melted metallic material upwardly through the fill tube into the mold. Extraneous sulfur is prevented from entering the molten metal from the surrounding environment.

A die casting method includes stirring an aluminum alloy liquid in a stirrer under an airtight vacuum condition. The stirrer includes an electromagnetic inductor and a stirring rod. The aluminum alloy liquid is simultaneously subjected to an electromagnetic stirring in a direction of a magnetic field generated by the electromagnetic inductor and a mechanical stirring under a rotation action of the stirring rod. The aluminum alloy liquid is stirred for 20-80 minutes until the aluminum alloy liquid becomes semisolid to obtain a semisolid aluminum alloy slurry. The method further includes injecting the semisolid aluminum alloy slurry into a filter die to perform die casting molding at an injection speed of 1.5-2.5 m/s, an injection specific pressure of 30-80 MPa, a pressurization pressure of 60-80 MPa, and a temperature of the filter die of 250-400° C., and maintaining pressure for 7-30 seconds to obtain the filtering cavity.

A die casting method includes stirring an aluminum alloy liquid in a stirrer under an airtight vacuum condition. The stirrer includes an electromagnetic inductor and a stirring rod. The aluminum alloy liquid is simultaneously subjected to an electromagnetic stirring in a direction of a magnetic field generated by the electromagnetic inductor and a mechanical stirring under a rotation action of the stirring rod. The aluminum alloy liquid is stirred for 20-80 minutes until the aluminum alloy liquid becomes semisolid to obtain a semisolid aluminum alloy slurry. The method further includes injecting the semisolid aluminum alloy slurry into a filter die to perform die casting molding at an injection speed of 1.5-2.5 m/s, an injection specific pressure of 30-80 MPa, a pressurization pressure of 60-80 MPa, and a temperature of the filter die of 250-400° C., and maintaining pressure for 7-30 seconds to obtain the filtering cavity.

Systems, methods, components, and parts are provided for improving casting and electroplating performance of a plated cast part by doping a semiconductor material with an electrically active dopant before mixing the semiconductor material into a base material. The doped semiconductor material improves the castability of the base material and has an improved electrical conductivity which is closer to that of the base material such that a consistency of a subsequent plating on the part is improved.

The present application provides a composite brake disc, the preparation method thereof and a friction stir tool. The composite brake disc comprises: an aluminum alloy base layer, and an aluminum matrix composite layer, where the aluminum alloy base layer and the aluminum matrix composite layer are bonded with each other through metallurgical bonding. A transition layer is formed at the boundary surface where the aluminum alloy base layer and the aluminum matrix composite layer are bonded with each other. A reinforced structure connecting the aluminum alloy base layer and the aluminum matrix composite layer is formed in the transition layer. The solutions according to the present application can increase the volume fraction of reinforcement particles in the aluminum matrix composite layer, thus increasing wear resistance, can avoid further addition of ceramic particles into the aluminum alloy base layer, thus increasing the strength and elongation of the aluminum alloy base layer, reducing the failure risk, and increasing the thermal conductivity of the aluminum alloy base layer, so that the heat generated by the friction layer is transferred to the air, thus reducing the overall temperature rise of the brake disc. In addition, the aluminum matrix composite layer in the solutions plays the role of a wear-resistant layer, and a transition layer is formed between the aluminum matrix composite layer and the aluminum alloy base layer through metallurgical bonding. The transition layer can prevent the volume fraction of ceramic particles between the aluminum matrix composite layer and the aluminum alloy base layer from changing instantly, thus reducing the stress difference between the aluminum matrix composite layer and the aluminum alloy base layer due to cold and hot fatigue, and increasing the bonding force between the aluminum matrix composite layer and the aluminum alloy base layer, so as to reduce the failure risk due to cracking between the aluminum matrix composite layer and the aluminum alloy base layer as a result of cold and hot fatigue and so on.

The present application provides a composite brake disc, the preparation method thereof and a friction stir tool. The composite brake disc comprises: an aluminum alloy base layer, and an aluminum matrix composite layer, where the aluminum alloy base layer and the aluminum matrix composite layer are bonded with each other through metallurgical bonding. A transition layer is formed at the boundary surface where the aluminum alloy base layer and the aluminum matrix composite layer are bonded with each other. A reinforced structure connecting the aluminum alloy base layer and the aluminum matrix composite layer is formed in the transition layer. The solutions according to the present application can increase the volume fraction of reinforcement particles in the aluminum matrix composite layer, thus increasing wear resistance, can avoid further addition of ceramic particles into the aluminum alloy base layer, thus increasing the strength and elongation of the aluminum alloy base layer, reducing the failure risk, and increasing the thermal conductivity of the aluminum alloy base layer, so that the heat generated by the friction layer is transferred to the air, thus reducing the overall temperature rise of the brake disc. In addition, the aluminum matrix composite layer in the solutions plays the role of a wear-resistant layer, and a transition layer is formed between the aluminum matrix composite layer and the aluminum alloy base layer through metallurgical bonding. The transition layer can prevent the volume fraction of ceramic particles between the aluminum matrix composite layer and the aluminum alloy base layer from changing instantly, thus reducing the stress difference between the aluminum matrix composite layer and the aluminum alloy base layer due to cold and hot fatigue, and increasing the bonding force between the aluminum matrix composite layer and the aluminum alloy base layer, so as to reduce the failure risk due to cracking between the aluminum matrix composite layer and the aluminum alloy base layer as a result of cold and hot fatigue and so on.

A method for manufacturing an austempered ductile cast iron and a product made from the austempered ductile cast iron manufactured by the method are disclosed. In the method for manufacturing an austempered ductile cast iron, spheroidizing agent and primary inoculant are added to a raw molten metal to create homogeneous spheroidal graphite creation in a deep part of a matrix and the raw molten metal to which the spheroidizing agent and the primary inoculant are added is injected into a mold to which secondary inoculant is locally applied, to micronize spheroidal graphite of a local structure coated with the secondary inoculant into fine graphite that is easy to machine, thereby enhancing workability as compared with a conventional austempered ductile cast iron.

An apparatus for countergravity casting a metallic has: a crucible for holding melted metallic material; a casting chamber for containing a mold; a fill tube capable of extending into the crucible to communicate melted metallic material to the casting chamber; and a gas source coupled to a headspace of the melting vessel to allow the gas source to pressurize said headspace to establish a pressure differential to force the melted metallic material upwardly through said fill tube into the mold. Added sulfur-gettering particles subsequently filtered or sulfur-gettering material removes sulfur from the melted metallic material.

An apparatus for countergravity casting a metallic has: a crucible for holding melted metallic material; a casting chamber for containing a mold; a fill tube capable of extending into the crucible to communicate melted metallic material to the casting chamber; and a gas source coupled to a headspace of the melting vessel to allow the gas source to pressurize said headspace to establish a pressure differential to force the melted metallic material upwardly through said fill tube into the mold. Added sulfur-gettering particles subsequently filtered or sulfur-gettering material removes sulfur from the melted metallic material.

Additive for the thermochemical treatment of molten iron in order to separate, distribute, agglomerate, precipitate, spheroidize and/or crystallize combined, solvated and/or colloidal carbon present in molten iron in the liquid state into graphite in its hexagonal diamond or Lonsdaleite form, in order to produce ductile, nodular, spheroidal, vermicular, coral, spheroidized or grey iron with superior mechanical properties, iron with high metal yield and zero contraction during casting; the additive comprises two or more elements in the metallic state selected from the S-block of periods 2 to 7 of the periodic table of elements; and two or more elements in the metallic state selected from F-block of periods 6 to 7 of the periodic table of elements. The additive makes it possible to produce cast iron parts with Type I and II spheroidal graphite in hexagonal diamond or Lonsdaleite form as per the ASTM-A247 standard.