Abstract: The invention relates to a foundry core for cast pieces of aluminium alloy in a mold, said core comprising a molding part, intended to be in contact with the molten aluminium alloy, and at least one non-molding part intended to be located outside the molten aluminium alloy, the core comprising at least one slot on the surface of the core, said slot extending from the molding part to at least one non-molding part for discharge of the gases generated in the molding part of the core during casting outside the molding part.

Abstract: The invention relates, according to a first aspect, to a process for the heat treatment of a cylinder head-type casting made from an aluminum alloy, in particular an alloy of aluminum, of silicon and of magnesium, and where appropriate of copper, comprising the steps of: —solution annealing (L) of the part for a time between three and ten hours; —quenching (S) of the part in air or in a fluidized bed; —tempering (H) of the part at the peak of resistance, or in the vicinity of the peak of resistance to attain a level of resistance of the part at least equal to 85% of the maximum level of resistance at the tempering temperature in question. According to a second aspect, the invention relates to the castings obtained at the end of the process according to the invention, and which have an improved fatigue resistance.

Abstract: The present invention relates to a castable heat resistant aluminum alloy for high temperature applications such as components in combustion engines, in particular for the manufacturing of highly loaded cylinder heads, the alloy comprises the following composition: .Si: 6.5-10 wt %.Mg: 0.25-0.35 wt %.Cu: 0.3-0.7 wt %.Hf: 0.025-0.55 wt % Optionally with the addition of: .Ti: 0-0.2 wt %.Zr: 0-0.3 wt %, the balance being made of Al and unavoidable impurities including Fe.

Abstract: The invention relates according to a first aspect to a method for the heat treatment of a batch of castings, in which an air quench is applied to the castings of the batch that are arranged in a single layer. The invention also extends to a system for the heat treatment of a batch of castings that includes a ventilation system in order to cause a flow of cooling air, characterized in that it includes means for placing the castings of the batch in a single layer and means for bringing the single layer of castings beneath the ventilation system so as to apply an air quench to the single layer comprising the castings of the batch.

Abstract: The invention relates, according to a first aspect, to a process for the heat treatment of a cylinder head-type casting made from an aluminium alloy, in particular an alloy of aluminium, of silicon and of magnesium, and where appropriate of copper, comprising the steps of: —solution annealing (L) of the part for a time between three and ten hours; —quenching (S) of the part in air or in a fluidized bed; —tempering (H) of the part at the peak of resistance, or in the vicinity of the peak of resistance to attain a level of resistance of the part at least equal to 85% of the maximum level of resistance at the tempering temperature in question. According to a second aspect, the invention relates to the castings obtained at the end of the process according to the invention, and which have an improved fatigue resistance.

Abstract: The invention relates according to a first aspect to a method for the heat treatment of a batch of castings, in which an air quench is applied to the castings of the batch that are arranged in a single layer. The invention also extends to a system for the heat treatment of a batch of castings that includes a ventilation system in order to cause a flow of cooling air, characterized in that it includes means for placing the castings of the batch in a single layer and means for bringing the single layer of castings beneath the ventilation system so as to apply an air quench to the single layer comprising the castings of the batch.

Abstract: A method of heat-treating a casting made of an aluminum-based alloy including an alloy of aluminum, silicon, and magnesium comprising heat treating the casting at a first temperature range for a first duration; gradually cooling the casting to a second temperature having a second temperature range; maintaining the casting at the second temperature range for a second duration; quenching the casting; and age hardening the casting.

Abstract: The invention concerns a method for casting a part made of metal alloy such as an aluminum alloy comprising the following steps: forming a core (N, PNC) having at least one shaft (PC) designed to form in the part a cylinder and at least one cavity (P) designed to form in the part a support and/or retaining zone for a working member, and at least a cooling unit (RE) proximate to the cavity; positioning the core in a metal mould cavity, and feeding the mould lined with its liquid alloy core by gravity. The invention is particularly useful for casting internal engine cylinder blocks with aluminum cylinders with improved geometrical and mechanical properties of the crankshaft bearing zones.

Abstract: A process of fabricating a light alloy casting, such as an aluminum alloy casting, including at least one metal insert includes applying a coating of lampblack to a face of the insert intended to be in contact with the alloy of the component and casting the component with the molten alloy in a mold cavity in which the insert is positioned. Applications include fabricating engine blocks with integrally cast liners made of cast iron.

Abstract: A test stand for cylinder head components of an internal combustion engine includes at least one combustion or pressure chamber. The test stand supplies a hydraulic fluid to the chamber, and controls the pressure of the hydraulic fluid to simulate pressure cycles in the chamber. The test stand controls the pressure with at least one source of high-pressure hydraulic fluid, the high-pressure being at an adjustable and constant level, at least one solenoid valve per chamber, receiving hydraulic fluid from the high-pressure source, and automatically drives each solenoid valve as a function of the pressure in the chamber and a set-point pressure, so that each solenoid valve feeds this chamber with hydraulic fluid the pressure of which is controlled at any time by the solenoid valve and simulates predetermined pressure cycles as a function of time.

Abstract: The invention provides equipment for molding castings in a mold having at least one sand core (Na1), in which the positioning of the or each core is obtained by the core co-operating with an element (S) of the mold, in particular a metal mold element. This equipment is remarkable in that the or each core possesses an insert (I) secured to the core while making said core and via which said core is suitable for co-operating with the mold element in question. The invention also provides an associated method of positioning cores. The invention is particularly applicable to improving the positioning of admission pipes in light alloy cylinder heads for engines.

Abstract: The invention relates to a wheel rim made from a light alloy, such as an aluminium-based alloy, comprising a front face (10) and a tyre tread (20) which are welded together. The inventive method of producing the wheel rim (J) comprises the following steps: moulding of the front face (10) with a light alloy; provision of a weldable alloy strip with structural hardening; curving of said strip to produce a generally cylindrical shape; welding of the ends in relation to the curved strip with fusion of the strip material; forming of the strip by necking and/or spinning in order to form the tyre tread (20); and welding of the front face and the tyre tread to one another.

Abstract: A thermal fatigue test stand for combustion engine cylinder heads. A cylinder head support having at least a cylinder head zone capable of being exposed to the engine combustion. At least one burner for directing a flame on the entire head zone. At least one heat flux sensor located in the cylinder head thickness at the zone to verify whether the heat flux produced by the flame is at least approximately in conformity with a predetermined value. The invention also concerns a method for calibrating such a test stand, and a method for testing cylinder heads. The invention is particularly useful for developing, both from a metallurgical and geometrical viewpoints, aluminum alloy cylinder heads.

Abstract: A process for molding a casting made of light alloy comprises the steps consisting in: preparing a mold with a print made of physically setting sand, incorporating a movable closure means in the mold near a feed runner of the mold, placing the mold in such a way that its feed runner is in the lower part, connecting the feed runner of the mold to a tube for feeding with a pressurized molten alloy, filling the mold with said alloy, before any substantial solidification of the casting, moving the closure means in order to close off the feed runner, then rotating the mold through approximately 180° in order to ensure solidification in gravity mode. Application especially to the manufacture of engine blocks for motor vehicles.

Abstract: The disclosure relates to a process for producing molded parts, made of aluminum or an aluminum alloy and having integrated channels intended for the distribution of a lubricant or for the circulation of a liquid coolant. In the process one or more tubes, made of aluminum or an aluminum alloy and previously formed, are placed in a mold, the ends of the tube or tubes being on the outside of the mold or of the cores inserted therein. The aluminum or alloy is poured into the cavity of the mold, and after demolding, the surplus portions of the tube or tubes are eliminated. This process is used for the mass production of molded parts having a system of internal channels, such as cylinder heads, compressor cylinders, lubrication systems, convectors, etc.

Abstract: This invention relates to a fatigue test bench for engine cylinder heads, particularly for motor vehicles. This bench comprises as main elements: a device for fixing the test cylinder head on an intermediate connecting member, connecting it to the means of establishing hydraulic pressure in the combustion chambers and in the circulating of the heat bearing fluids; a pressure generating device which simulates as faithfully as possible and in a reproducible manner the pressure cycle as a function of time in the combustion chambers; and a system of circulating heat bearing fluids through the water chambers of the cylinder head with two differnt circuits, one at ambient temperature and the other at a higher temperature used alternately by means of a regulable timing device which controls the operation of one or other of the circuits.

Abstract: The present invention relates to a process for the production of composite alloys based on aluminum, which may or may not be alloyed, and containing up to 30% by weight of boron.The process is characterized in that the boron is introduced into the liquid aluminum in the form of aluminum boride having the formula AlB.sub.2 or AlB.sub.12.It finds application in the production of composite alloys which are resistant to abrasion or which are intended to serve as neutron barriers in air or an aqueous medium.