There is provided a heat exchanger and a fin material for the heat exchanger that can suppress occurrence of hollow corrosion in a fin and hold cooling performance for a long period of time under a high corrosion environment. The heat exchanger includes an aluminum tube through which a working fluid circulates and an aluminum fin which is bonded to the tube. The fin has a region B around a grain boundary, and a region A around the region B. In the region B, 5.010.sup.4 pieces/mm.sup.2 less of AlFeMnSi based intermetallic compound, each of which has equivalent circle diameters of 0.1 to 2.5 m, are present. In the region A, 5.010.sup.4 pieces/mm.sup.2 to 1.010.sup.7 pieces/mm.sup.2 of AlFeMnSi based intermetallic compound, each of which has equivalent circle diameters of 0.1 to 2.5 m, are present.

An energy coupling device for coupling energy into molten metal. The energy coupling device includes a cavitation source which supplies energy through a cooling medium and through a receptor in contact with the molten metal. The cavitation source includes a probe disposed in a cooling channel. The probe has at least one injection port for injection of a cooling medium between a bottom of the probe and the receptor. The probe under operation produces cavitations in the cooling medium. The cavitations are directed through the cooling medium to the receptor.

A method for combined rolling and extruding of cast billet is proposed. When implementing the method for combined rolling and extruding of metals or alloys, a cast billet with a predetermined temperature is fed to the working gauge, in which it is rolled and then to the die, through which the cast billet is extruded. When the cast billet is fed into the working gauge, a cladding layer of metal or alloy is created on the surfaces of the rolls by extruding the cast billet through the gaps formed between the surfaces of the rolls and the die. This invention makes it possible to improve the quality of the resulting products, as well as to increase the efficiency of the process as a whole.

A method for the continuous casting of metal strands. The liquid metal is simultaneously cast via a molds into metal strands. The molds each have a narrow side and a broad side. The molds have a uniform narrow side so that the metal strands have equal thicknesses after casting. At least one of the molds used has a broad side whose length differs from the length of the broad side of the other simultaneously used molds. For each mold used, a sprue stone is provided, which is arranged on a casting table and is provided for receiving the starter strands. The casting of the metal strands includes a mold filling phase with a fixed casting table in which a plurality of starter strands is cast into the associated sprue stones. The casting includes a continuous casting phase in which the casting table is lowered and metal strands are cast.

Aluminum alloys having improved high temperature mechanical properties are provided. An aluminum alloy suitable for sand casting, permanent mold casting, or semi-permanent mold casting includes about 3 to about 12 weight percent silicon; about 0.5 to about 2.0 weight percent copper; about 0.2 to about 0.6 weight percent magnesium; about 0 to about 0.5 weight percent chromium; about 0 to about 0.3 weight percent each of zirconium, vanadium, cobalt, and barium; about 0 to about 0.3 weight percent each of strontium, sodium, and titanium; about 0 to about 0.5 weight percent each of iron manganese, and zinc; and about 0.0.1 weight percent of other trace elements. Also disclosed is a semi permanent mold cast article, such as an engine cylinder head.

An aluminum alloy fin material includes an aluminum alloy containing 1.50 to 5.00 mass % Si with the balance of Al and inevitable impurities, and has the function of being bonded by heating with a single layer. Assuming that in a cross section along the thickness direction of the fin material, the equivalent circle diameter of a Si particle is represented by D, a distance from a surface layer to the center of the Si particle is represented by L, the thickness of the fin material is represented by t, and a length parallel to the surface layer is represented by W, all Si particles that are present in the range of the length W and satisfy DL and L+D>0.04 t also satisfy 0D.sup.2<0.08 tW. An aluminum alloy brazing sheet includes, as a skin material, the fin material that is clad on a core material including an aluminum alloy. A heat exchanger includes the fin material or the brazing sheet that is used in a fin.

Provided is an aluminum alloy forging material having an alloy composition including Cu: 0.30 mass % to 1.0 mass %, Mg: 0.80 mass % to 1.8 mass %, Si: 0.90 mass % to 1.9 mass %, Mn: 0.30 mass % to 1.2 mass %, Fe: 0.20 mass % to 0.65 mass %, Zn: 0.25 mass % or less, Cr: 0.050 mass % to 0.30 mass %, Ti: 0.01 mass % to 0.1 mass %, B: 0.0010 mass % to 0.030 mass %, and Zr: 0.0010 mass % to 0.050 mass %, and having a ratio Fe/Mn of less than 1.4, and with the remainder being made up of Al and unavoidable impurities, wherein an average crystal particle size of an alloy structure after forging is 50 ?m to 120 ?m, and an average crystal particle size of an AlFeSi(Mn)-based compound present at crystal grain boundaries is 3.0 ?m or less.

The present disclosure relates to an aluminum alloy material, and specifically to a weldable in-situ nano-strengthened rare-earth metal (REM)-containing aluminum alloy with high strength and toughness and a preparation method thereof. In the present disclosure, in-situ nano-ceramic particles and REMs simultaneously introduced into an AlZnMg alloy can effectively refine the grains and significantly improve the strength and toughness of the alloy; and REM-containing nano-precipitated phases and in-situ nanoparticles distributed in the grains or at grain boundaries can also significantly increase a recrystallization temperature of the alloy, effectively inhibit the dynamic recovery, reduce the re-dissolution of alloying elements, and improve the weldability of the alloy.

An AMC, and in particular to an AMC with high strength, high toughness, high thermal conductivity, and good weldability for a 5G base station and a preparation method thereof. A strip of the AMC with high strength, high toughness, high thermal conductivity, and good weldability for a 5G base station can be prepared by an electromagnetically and ultrasonically-controlled twin-roll continuous casting device developed and designed based on chemical composition designing, in-situ nanoparticle strengthening and refinement, and REM microalloying. The composite strip prepared by this technology has fine grains, nano-REM precipitated phases in grains, and in-situ nano-ceramic particles with high thermal conductivity at grain boundaries, which significantly improves strength, toughness, and thermal conductivity of the alloy at room temperature, and increases a grain boundary content and effectively improves roll cold weldability of the alloy strip since the alloy composition design with a low melting point and the significant grain refinement.

A molten metal conveyor having a receptor plate in contact with molten metal during transport of the molten metal. The receptor plate extends from an entrance where molten metal enters onto the receptor plate to an exit where molten metal exits the receptor plate. The molten metal conveyor has at least one vibrational energy source which supplies vibrational energy directly to the receptor plate in contact with molten metal. A corresponding method for forming a metal product includes providing molten metal onto a molten conveyor; cooling the molten metal by control of a cooling medium flowing through a cooling passage in the or attached to the conveyor; and coupling vibrational energy directly into a receptor plate in contact with the molten metal on the conveyor.