HOME > Topics


Previous Topics

2012 Japan Powder Metallurgy Association Awards

We have been awarded by 2012 Japan Powder Metallurgy Association for following innovations and developments.


■Category: New Design

Development of Variable Valve Timing Parts on the Exhaust Side for Eco-Friendly Car

The products are the rotor and the housing for the variable valve timing system for an eco-friendly car.
Because the response of the variable valve timing system on the exhaust side is important to exhaust gas smoothly and quickly, the higher precision and weight saving are demanded under the condition of cost reduction.
In this development, the combination of the shapes of the rotor and the housing was designed to avoid drilling holes for setting springs. Higher precision was achieved by the optimization of productive conditions, which resulted in obtaining enough tight tolerance between the rotor and the housing for sealants free. Moreover, blind holes on the rotor were formed by compaction, which resulted from improved powder flow and optimized tool design and material.


Development of Sintered Coupling for Engine Balancer for Clean Diesel Vehicle

This product is a coupling for the balancer for a clean diesel engine with low emission of CO2, PM, NOx etc.
The part works as connection between crankshaft and balancer where high precision is required for assembly, and is required wear resistance and high strength.
In order to obtain cost advantage to wrought steels, the part is produced without machining. High precision is achieved by optimum tool design and material based on FEM analysis, and by optimization of compacting conditions for the improvement on the density distribution. A Fe-Mo-C system steel is selected for the material of the part from the view point of wear resistance against strong vibration and high torque.


Development of Sintered Bearings for the Poppet Valves for EGR system

The products are sintered bearings for the poppet valves for EGR (Exhaust Gas Recirculation) system.
Generally, the bearing material was made from graphite to endure the tribological properties at the high temperature of 250℃, and was machined out for inner asymmetric shape to inhibit valve rotation.
In this development, a new PM material was developed to replace the graphite bearings. The new material is Cu-Sn-C material with high carbon content of more than 6mass% to satisfy high temperature tribological properties. The microstructures of the material consist of Cu-Sn matrix and uniformly dispersed graphite phase. Graphite phase also seals pores, which results in preventing oxidation. Furthermore, machining free process was adopted, especially the guide part of asymmetric inner hole, which improves insert of valve to the bearing, was shaped by sizing.

Back to TOP Page