Development of Ultra Fine Grain Steel for Carburizing Daido Steel Company, Limited

Format:

Conference/Event

Author/Creator:

Kurebayashi, Yutaka, author.

Conference Name:

International Congress & Exposition (1995-02-27 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 1995

Summary:

The cold forging process is one of the most popular in the manufacture the automotive parts such as gears and shafts, cold forging saves material and machining costs by near-net shape the principle of forming. However, abnormal austenite grain growth sometimes occurs when the cold forged parts are heated for surface carburizing without a prior normalizing process. The size of the coarse grains can be large, sometimes ASTM Grain Size Number -2 to -4. The abnormal grain growth may cause post-carburizing distortion and is harmful to both fracture toughness and fatigue strength of the parts [1]. The purpose of our research was to develope new steels which would keep the fine grains during the carburizing treatment without normalizing.First, we studied the influence of elements on the grain growth property of case hardening steels and Naiobum (Nb) was selected as the element to control the grain growth. Secondly, we developed an ultra fine grain steel containing a small amount of Nb. The new steel keeps fine grain after cold forging and heating for 72 ks at 1223 K.

Notes:

Vendor supplied data

Publisher Number:

950209

Access Restriction:

Restricted for use by site license