A sprocket wheel, which is a machine component configured to slide relative to a bushing while being in contact with the bushing in an outer peripheral surface, includes a base made of a first metal, and an overlay that covers the base so as to constitute the outer peripheral surface. The surface of the overlay constituting the outer peripheral surface has been smoothed. Such a smoothed surface of the overlay makes the sprocket wheel less damaging to the bushing.

The present invention concerns a method for producing a bicycle component (10), characterised in that it comprises the following consecutive operations: a step of producing a part (15) comprising an inner cavity (52) that is open on one side; a step of positioning a plate (60) on the part (15) in order to cover the cavity (52); and a step of securing the plate (60) to the part (15) in order to obtain the bicycle component (10). The invention also concerns a bicycle component (10) and a bicycle chainset.

The inventive concept relates to a method for manufacturing a metal based frame comprising the steps of: providing a first element (202) comprising a first element inner enveloping wall (204) surrounding an interior volume; providing a second element (210) having a second element outer wall (212), a second element inner wall (213), and a third element (220) having a third element outer wall (222), a third element inner wall, wherein the second element inner wall (213)and the third element inner wall each surrounds a free space (215); arranging the second element (210) and the third element (220) in the interior volume (208) such that an intermediate space (230) having an access opening (232) is formed between the first element inner enveloping wall (204) and the second element outer wall (212) and the third element outer wall (222) in a predetermined pattern; arranging a plurality of pieces of a wrought material (250) in the intermediate space (230); providing a closing member (240) arranged such that it covers at least the access opening (232) of the intermediate space (230), whereby the first element (202), the second element (210), the third element (220), the plurality of pieces of a wrought material (250), and the closing member (240) form an assembled frame arrangement (200); removing gas from the intermediate space; subjecting the assembled frame arrangement to a hot pressing process for a predetermined time at a predetermined pressure and a predetermined temperature such that at least the plurality of pieces of a wrought material bond metallurgically to each other, to form the metal based frame.

A method for producing a structural component, which has different component sections, from a high-strength alloy material. The structural component to be produced is divided into at least two component sections which differ with respect to their requirement profiles when the structural component is later used, wherein one component section must meet a higher requirement profile with respect to occurring loads, and the at least one other component section must meet a lower requirement profile. In a first production step for producing the component section with the higher requirements, a blank is brought to near-net-shape or net-shape by a massive forming process in some regions. To form the at least one component section with the lower requirement profile, a body in the form of a pre-manufactured part, which corresponds to said component section, is arranged on at least one surface region in the form of a substrate, which has not yet been brought into its near-net-shape or net-shape by the massive forming process, and is bonded to the blank in at least one following step, and/or said component section is attached to the provided surface region of the blank by a generative production method in order to also bring the aforementioned regions of the massive-formed component section to a near-net-shape. The semi-finished product produced in this manner, as a completed preform, is then brought to its net-shape in one or more steps.

A combined ultrasonic micro-forging device and a related additive manufacturing method for improving the microstructure and mechanical properties of additive manufactured metal part. The device comprises a transducer, a pneumatic sliding table, a pneumatic sliding table connecting frame, an amplitude transformer, a tool head and a roller, wherein the transducer is provided in a transducer housing, a socket connector and a pipeline connector are provided on the transducer housing, the amplitude transformer is connected under the transducer, the tool head is connected under the transducer, the roller is located between the tool head and workpiece, and the pneumatic sliding table is connected to the transducer housing and the amplitude transformer via the pneumatic sliding table connecting frame. The ultrasonic micro-forging device of high frequency ultrasonic impact and larger deformation produced by mechanical rolling, thereby generating a composite action of ultrasonic impact and continuous rolling micro-forging.

A method for manufacturing a bicycle crank is revealed. After being extended, bent and forged, an aluminum alloy pipe becomes an L-shaped part formed by a cylindrical crankshaft portion and an oval crank portion integrally connected to each other. A plug is inserted into an outer end of the crank portion while a periphery of an outer end of the crankshaft portion is punched to form a shaft-connecting portion. An assembling hole is arranged at the outer end of the crank portion, corresponding to the plug. Thus a bicycle crank is produced. Thereby not only the assembly of the bicycle crank is easier and more convenient, the structural strength of the bicycle crank is increased effectively to against vibrations and impacts. The bicycle is lightweight and the bicycle crank is more streamlined so that consumers are attracted. Thereby the market competitiveness is increased.

In a die for compressing and sizing a sintered body at straight portions, upper taper portions are provided on a die upper portion and a core rod upper portion, and the straight portions are provided at a die lower portion and a core rod lower portion. The die upper portion and the core rod upper portion have Young's moduli higher than the die lower portion and the core rod lower portion. The die upper portion and the core rod upper portion are made of materials having Young's moduli that are at least 50 GPa higher than that of the sintered body. The sintered body can be densified with a smaller ironing margin. Since the sintered body is ironed without being compressed, by the upper taper portions and the core rod upper portion having high Young's moduli, the die is prevented from breaking and being abraded due to ironing.

A method for manufacturing a blade, the method includes casting a nickel alloy blade precursor having an airfoil and a root. The airfoil and the root are solution heat treating differently from each other. After the solution heat treating, the root is wrought processed. After the wrought processing, an exterior of the root is machined.

A forging device for molten metal includes first and second die bodies that are linked by first and second power arms to move back and forth in a cavity of a die base so as to open and close a workpiece shaping space defined between first and second die faces of the first and second die bodies. When the workpiece shaping space is opened, a molten metal is poured, and then the workpiece shaping space is closed to cast a semi-finished workpiece. After that, the first and second power arms axially press and forge the semi-finished workpiece in the workpiece shaping space into a high-strength workpiece. The high-strength workpiece is shaped by casting and forging in the same process.

There is provided a method of manufacturing a component. The method comprises creating a preform from a material using additive manufacturing and heat treating the preform at a heating temperature to modify the microstructure of the material. The preform is geometrically unconstrained during the step of heat treating. The method then comprises compressive forming the preform into a predefined arrangement to create the component wherein the step of compressive forming is effective to close pores and diffusively bond the material. The material may then be geometrically constrained as it is cooled, for example within the die used for compressive forming.