Abstract:
In a method for manufacturing a camshaft for an internal combustion engine a metal tubular element is expanded within a mold with the aid of a fluid at high pressure fed into the tubular element and with a simultaneous axial compression of the tubular element. The cams of the camshaft are formed in subsequent steps, starting from intermediate cams and ending with end cams. In a first step of the method, the intermediate cams are formed in a first mold. In a subsequent step, the end cams are formed within auxiliary molds which surround, only throughout a predetermined length, end portions of the tubular element which project from the mold which surrounds the already formed intermediate cams. In this subsequent step, the tubular element is compressed axially by axially displacing two clamp members, which grip and surround completely, throughout a predetermined length, the end portions of the tubular element which project outwardly from the auxiliary molds.
Abstract:
In a method for manufacturing a camshaft for an internal combustion engine a metal tubular element is expanded within a mould with the aid of a fluid at high pressure fed into the tubular element and with a simultaneous axial compression of the tubular element. The cams of the camshaft are formed in subsequent steps, starting from intermediate cams and ending with end cams. In a first step of the method, the intermediate cams are formed in a first mould. In a subsequent step, the end cams are formed within auxiliary moulds which surround, only throughout a predetermined length, end portions of the tubular element which project from the mould which surrounds the already formed intermediate cams. In this subsequent step, the tubular element is compressed axially by axially displacing two clamp members, which grip and surround completely, throughout a predetermined length, the end portions of the tubular element which project outwardly from the auxiliary moulds.
Abstract:
A component of a vehicle structure is obtained by a hot forming operation on a hybrid panel having a sheet element of light alloy and a sheet of plastic material. The hybrid panel is hot formed by pressing it against a forming surface of a mould element by a pressurized gas or by a second mould element. Following this operation, the hybrid panel assumes a configuration corresponding to the forming surface, whereas the light alloy sheet element and the plastic material sheet constituting the hybrid panel adhere to each other following softening by heat of the plastic material. Before the hot forming step, a surface of said light alloy sheet element which must contact the plastic material sheet is subjected to a roughening treatment, thereby defining surface asperities between which the plastic material of the plastic material sheet is inserted when it is softened by heat.
Abstract:
Described herein is a method for rolling metal sheets of variable thickness. The method makes it possible to impress, during rolling, any distribution of areas of increased thickness within a figure corresponding to the plane development of a motor-vehicle component prior to the pressing operation. Impression of the desired distribution of areas of increased thickness envisages simultaneous impression, during rolling, of a further distribution of areas of increased thickness, or compensation areas.
Abstract:
A method for forming a sheet made of an aluminium alloy into a component of complex shape, particularly a motor-vehicle component, such as an outer panel or an inner frame of a bonnet or a door of a motor-vehicle, provides for blow-forming of the sheet, with the aid of pressurized gas, within a mould. The alloy constituting the sheet does not have superplasticity features and the sheet and/or the mould are heated to a temperature in the order of 400°-450° C. for 5XXX series alloys and 450°-500° C. and over for 6XXX and 7XXX series alloys. The maximum pressure reached by the forming gas is in the order of 20-30 bars and the time required for forming the sheet is between 40 and 150 seconds and therefore is consistent with production rates in the automotive field.
Abstract:
A method for forming a sheet made of an aluminium alloy into a component of complex shape, particularly a motor-vehicle component, such as an outer panel or an inner frame of a bonnet or a door of a motor-vehicle, provides for blow-forming of the sheet, with the aid of pressurized gas, within a mould. The alloy constituting the sheet does not have superplasticity features and the sheet and/or the mould are heated to a temperature in the order of 400°-450° C. for 5XXX series alloys and 450°-500° C. and over for 6XXX and 7XXX series alloys. The maximum pressure reached by the forming gas is in the order of 20-30 bars and the time required for forming the sheet is between 40 and 150 seconds and therefore is consistent with production rates in the automotive field.
Abstract:
A method for obtaining a camshaft for an internal-combustion engine having a structure made of a single piece includes obtaining the camshaft by starting from a metal tubular element. The cams are obtained by expanding the tubular element within a die using high-pressure fluid. The tubular element can have an enlarged thickness in portions that are to form the cams. Forming with high-pressure fluid can be obtained using gas or liquid (for example, water or oil) at high pressure, at room temperature or at a higher temperature. The piece obtained is subjected to thermal treatment and to a grinding operation.
Abstract:
The invention relates to a coating composition for metal surfaces comprising a polymer matrix and at least first and second functionalized nano-containers dispersed within the matrix and respectively containing active substances different from each other. Each of said first and second functionalized nano-containers defines a volume of nanometric size containing said active substance confined within a porous core and/or a porous shell that, in normal conditions, prevent the direct contact of the active substance with the external environment, while, in predetermined triggering conditions, allow the release of the active substance into external environment. The first functionalized nano-containers contain a corrosion inhibitor agent as the active substance, while the second functionalized nano-containers contain either an agent able to displace water or a precursor of a polymerizable species, able to form a polymeric layer such as to cover a damaged area and/or prevent the propagation of a crack or other defect, as the active substance.