MANUFACTURE OF RAIL HAVING SUPERIOR RESISTANCE TO IMPACT FRACTURE

Title:

MANUFACTURE OF RAIL HAVING SUPERIOR RESISTANCE TO IMPACT FRACTURE

Document Type and Number:

Japanese Patent JPS62227042

Kind Code:

A

Abstract:

PURPOSE: To manufacture a rail having superior resistance to impact fracture by subjecting the midsection and the bottom of a hot rolled rail whose head has a pearlite structure to martensitic transformation and temperating under specified conditions.

CONSTITUTION: The midsection and/or the bottom of a hot rolled rail or a hot rolled and heat treated rail whose head has a pearlite structure is hardened by heating to a temp. between a temp. above the A1 transformation point and 1,300°C and by uniform rapid cooling to cause martensitic transformation. The hardened part is then tempered by heating to a temp. between 400°C and a temp. below the A1 transformation point and immediately it is rapidly cooled. Thus, a rail having improved resistance to impact structure is obtd.

Inventors:

URASHIMA CHIKAYUKI
NISHIDA SHINICHI
SUGINO KAZUO
IWANO KATSUYA

Application Number:

JP7059086A

Publication Date:

October 06, 1987

Filing Date:

March 28, 1986

Export Citation:

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Assignee:

NIPPON STEEL CORP

International Classes:

C21D9/04; (IPC1-7): C21D9/04

Domestic Patent References:

JPS60103154A	1985-06-07
JPS59116321A	1984-07-05

Attorney, Agent or Firm:

Teruo Taniyama

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