49 Development of Pb-free Free-Cutting Steel Enabling Omission of Normalizing for Crankshafts Honda R&D Company, Limited

Format:

Book

Conference/Event

Author/Creator:

AMATAKA, Atsushi, author.

Conference Name:

Small Engine Technology Conference & Exposition (2002-10-29 : Kyoto, Japan)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Tokyo, JAPAN Society of Automotive Engineers of Japan 2002

Summary:

Crankshafts of motorcycles require high strength, high reliability and low manufacturing cost. Recently, a reduction of Pb content in the free-cutting steel, which is harmful substance, is required. In order to satisfy such requirements, we started the development of Pb-free free-cutting steel which simultaneously enabled the omission of the normalizing process. For the omission of normalizing process, we adjusted the content of Carbon, Manganese and Nitrogen of the steel. This developed steel can obtain adequate hardness and fine microstructure by air-cooling after forging. Pb-free free-cutting steel was developed based on Calcium-sulfur free-cutting steel. Pb free-cutting steel is excellent in cutting chips frangibility in lathe process. We thought that it was necessary that cutting chips frangibility of developed steel was equal to Pb free-cutting steel. It was found that cutting chips frangibility depend on a non-metallic inclusion's composition, shape and dispersion. By manufacturing a crankshaft with this steel, the cost of normalizing process was eliminated and reduction of Pb by 13 grams per vehicle became possible. The developed crankshafts have been applied in motorcycles equipped with four-stroke 954cm3 engine

Notes:

Vendor supplied data

Publisher Number:

2002-32-1818

Access Restriction:

Restricted for use by site license