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Transverse gear rolling has the potential to deliver both increased dimensional precision and performance in combination with the established processing methods for P/M gear manufacturing. In order to effectively design the rolling process, a constitutive understanding of both the kinematical boundary conditions and the densification behavior of different P/M materials is necessary. The successful application of a comprehensive process design strategy is illustrated along with highlights of several example products.

The paper studies the fracture splitting of powder forged (P/F) connecting rods, analyzes the effect of material, and compares the effect of machined V-notches and forged-in notches. Connecting rods made out of two different powder forged materials, P/F-11C59 and P/F-11C47 were statically and dynamically fractured. The fractured surface was analyzed using an SEM. Fracture mechanic tests were carried out with both materials using the disk-shaped compact test specimen according to the ASTM standard. The results show that the forged-in notch requires less force to fracture and that the ductile portion of the fracture surface is reduced. Furthermore, the lower carbon content of the material has no significant effect on fracture behavior but may offer the advantage of better machinability and ductility. Dynamic splitting may be an alternative solution to the current impact loading technology.

Connecting rods manufactured by the Precision Powder Forged (P/F) process offer several distinct advantages over those produced by all other methods including the state-of-the-art forged steel process. Precision P/F connecting rods have mechanical properties equivalent to those made from forged steel, with the added benefits of greater design flexibility, superior dimensional and weight precision, simplified finish machining and assembly, better machinability, and increased consistency because of highly stable metallurgy and a robust and reliable manufacturing process. The inherent flexibility of the P/F process also facilitates tailoring materials to achieve the optimal balance of strength and machinability for a given application. In combination, these advantages result in a product that requires less capital investment for finish machining, is more environmentally conscious by generating substantially less waste, exhibits better total performance, and has lower total cost.

A novel approach to the manufacture of high-performance powder metallurgy (P/M) sprockets and gears has been developed. The result is advanced components with a unique combination of properties tailored to the current needs of the marketplace. This dual material or “Duplex” method allows for the selective application of dissimilar yet compatible P/M alloys in order to optimize properties and reduce costs. In the example described, expensive sinter-hardening or induction-hardening materials were used for the teeth of an automotive camshaft timing sprocket, while the core consists of a low density and low cost material. Key advantages of this approach are reduced weight and rotational inertia, increased sound dampening properties, lower cost, and a reduction in the size of the press required for compaction. The paper describes this development and contrasts the advantages to the current manufacturing methods for components of this type.

Replacement of full density iron alloy components with parts manufactured from leading edge P/M technology continues to characterize new automotive product development. This presentation will identify these powertrain applications as well as define the significant cost savings associated with their implementation. Physical and mechanical properties of parts manufactured from processes such as ultra high density, hot forming and sinter hardening will be compared with each other as well as the materials they are replacing in the applications presented. Recommendations to maximize the automotive industry's involvement and benefit will also be discussed.