Abstract: An aluminum alloy brake disc body for a disc brake device is provided with a metal layer of a high wear-resistance. The high wear-resistance metal layer is configured to reduce thermal stresses within the aluminum alloy brake disc body so as to inhibit warping, bending or flexing of the brake disc when heated during braking. The high wear-resistant metal layer also is applied to the aluminum alloy brake disc body in a manner reducing manufacturing costs. In one mode, a plating layer made of a metal having a high wear-resistance is formed on a frictional surface of an aluminum alloy brake disc body. Cracks in the form of a fine network are formed in the whole area of the plating layer. The cracks can be formed by a plating process, by nitrosulphurization, by heating, by burnishing or by use of the plated component. The cracks advantageously provide for expansion between the individual metal fragments and, thus, create an expandable plated wear surface.

Abstract: An aluminum alloy brake disc body for a disc brake device is provided with a metal layer of a high wear-resistance. The high wear-resistance metal layer is configured to reduce thermal stresses within the aluminum alloy brake disc body so as to inhibit warping, bending or flexing of the brake disc when heated during braking. The high wear-resistant metal layer also is applied to the aluminum alloy brake disc body in a manner reducing manufacturing costs. In one mode, a plating layer made of a metal having a high wear-resistance is formed on a frictional surface of an aluminum alloy brake disc body. Cracks in the form of a fine network are formed in the whole area of the plating layer. The cracks can be formed by a plating process, by nitrosulphurization, by heating, by burnishing or by use of the plated component. The cracks advantageously provide for expansion between the individual metal fragments and, thus, create an expandable plated wear surface.

Abstract: The present invention is a piston for use in an internal combustion engine and a method of manufacturing the piston. In the method of the present invention, a first block comprising a first alloy and a second block comprising a second alloy are press-forged to form a piston. The piston has a head and a skirt, with the head comprising at least a portion of the first alloy and the skirt comprising at least a portion of the second alloy. The first alloy preferably comprises an aluminum-iron based alloy, and the second alloy preferably comprises an aluminum-silicon based alloy. Preferably, during the forging process an interface between the blocks is increased in length or area, whereby oxide layers on the blocks are destroyed and the material comprising the two alloys is bonded directly.

Abstract: A method of forming a piston for a reciprocating machine such as an engine. The piston is formed from a powdered material that is comprised of aluminum alloyed with a material selected from the group of silicon (Si) and iron (Fe) having a particle diameter not greater than 10 .mu.m. The resulting alloy is then forged into a piston having a piston head and a piston skirt. The powder which is solidified and forged is formed by a process comprising the steps of forming an ingot from an alloy comprised of aluminum and an alloying material. This ingot is then melted and dispersed as a liquid in a chilling stream to form powdered metal particles. These powdered metal particles are then compressed into a blank having a cylindrical configuration for subsequent forging.

Abstract: A composite piston and method for forming such a piston for a reciprocating machine such as an internal combustion engine. A blank is formed from a pair of dissimilar alloys, one of which has substantially greater properties such as strength or abrasion resistance. The blank is forged into a piston in such a way that the two materials are bonded together in the forging process. The higher strength and/or abrasion resistance material forms at least a part of the outer surface of the piston in areas where the better properties are required. The other material backs up the higher strength or hardness material in necessary areas so as to provide an integral structure that has lightweight, low costs and nevertheless the desired properties. Various physical constructions and forming operations are disclosed.

Abstract: A throttle control apparatus that maintains a vehicle's ability to run during a throttle system failure includes a throttle-controlling ECU that calculates a throttle opening instruction value from an accelerator stroke signal outputted from an accelerator pedal sensor, and supplies a motor with a current value based on the instruction value, to control the opening of a throttle valve. If the deviation between the instruction value and the output value from a throttle sensor is greater than a reference value, the ECU determines that there is a system failure. If it is determined that a system failure exists, an internal combustion engine controlling ECU varies the number of cylinders of the engine in operation to vary the engine output, depending on whether the amount of depression of the accelerator pedal by the driver is greater than a predetermined value.

Abstract: In a method of manufacturing the piston, a first block including first alloy and a second block including a second alloy are press-forged to form a piston. The piston has a head and a skirt, with the head including at least a portion of the first alloy and the skirt including at least a portion of the second alloy. The first alloy preferably including an aluminum-iron based alloy, and the second alloy preferably comprises an aluminum-silicon based alloy. Preferably, during the forging process an interface between the blocks is increased in length or area, whereby oxide layers on the blocks are destroyed and the material comprising the two alloys is bonded directly.