New hardening processes for transmission synchroniser hubs

ABSTRACT

Synchroniser hubs are powder metal components often used in vehicles for manual transmissions and dual clutch transmissions. Conventionally, these components are often through hardened, case carburised or induction hardened, although such processes can lead to deterioration of dimensional accuracy and increased costs. Synchroniser hubs which have both high strength and high dimensional accuracy are developed by optimising the material composition and introducing the newly developed roller-hearth-type high temperature sintering furnace. Besides, a laser hardening process can be applied locally to the necessary portion. Furthermore, the second whole hardening process and extra process cost can be eliminated using sinter-hardening process after high-temperature sintering.

KEYWORDS:

• Synchroniser hubs
• high strength
• wear resistance
• sinter-hardening
• roller-hearth-type high temperature
• sintering furnace

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Yuu Akiyama was an Application Engineer of Transmission parts in Development Division.

Terukazu Tokuoka was an Assistant General Manager of materials in Development Division.

Hiroaki Terai was a Group Manager of Transmission parts in Development Division.

Yuuki Adachi was a Group Manager in Production Engineering Department Material Engineering Group.

Nobuya Amano was a Director of Development Division.