Title:
PRODUCTION OF CARBURIZED HIGH STRENGTH SCREW EXCELLENT IN DELAYED FRACTURE RESISTANCE
Document Type and Number:
Japanese Patent JPH0967625
Kind Code:
A
Abstract:
To produce a carburized high strength screw excellent in cold forgeability and having superior delayed fracture resistance.
A steel, having a composition consisting of 0.05-0.15% C, ≤0.10% Si, ≤1.6% Mn, ≤0.010% P, ≤0.010% S, 0.01-0.05% Al, and the balance Fe with impurities, is used. This steel is treated with a lubricating film forming agent free from phosphorus, formed into a screw shape, and then subjected to carburizing, quenching, and tempering treatments. Moreover, a steel, containing, as steel components, one or ≥2 kinds among ≤0.10% Ti, ≤0.5% Cr, and ≤0.25% Mo, can be used.
Inventors:
KATO TAKEHIKO
NAMIMURA YUUICHI
HASEGAWA TOYOFUMI
NAMIMURA YUUICHI
HASEGAWA TOYOFUMI
Application Number:
JP22228895A
Publication Date:
March 11, 1997
Filing Date:
August 30, 1995
Export Citation:
Assignee:
KOBE STEEL LTD
International Classes:
C21D9/00; C22C38/00; C22C38/14; C22C38/28; (IPC1-7): C21D9/00; C22C38/00; C22C38/14; C22C38/28
Attorney, Agent or Firm:
Ueki Kuichi