HOT WORK TOOL STEEL HAVING EXCELLENT TOUGHNESS, AND PROCESS OF PRODUCING SAME

Title:

HOT WORK TOOL STEEL HAVING EXCELLENT TOUGHNESS, AND PROCESS OF PRODUCING SAME

Document Type and Number:

WIPO Patent Application WO/2012/118053

Kind Code:

A1

Abstract:

Provided are a hot work tool steel having improved toughness and a process of producing the hot work tool steel. A hot work tool steel comprising, in mass%, 0.3% or more and less than 0.6% of C, 1.5% or less of Si, 1.5% or less of Mn and 3.0% or more and less than 6.0% of Cr, wherein more than 0.0025% and 0.025% or less of Zn and 0.005% or more of P are contained and the Zn/P ratio is more than 0.5; and a process of producing a hot work tool steel, comprising a first step of preparing a molten steel having a chemical composition of a hot work tool steel containing 0.005 mass% or more of P, a second step of adding Zn to the molten steel having the chemical composition of the hot work tool steel, and a third step of casting the Zn-added molten steel to produce a steel ingot, wherein the second step is a step of adding Zn in such a manner that more than 0.0025 mass% and 0.025 mass% or less of Zn and 0.005 mass% or more of P can be contained in the chemical composition of the steel ingot after the casting in the third step and the hot work tool steel can have a Zn/P ratio of more than 0.5.

Inventors:

KATAOKA KOUTA (JP)
NAKANO YOUSUKE (JP)

Application Number:

PCT/JP2012/054868

Publication Date:

September 07, 2012

Filing Date:

February 28, 2012

Export Citation:

Click for automatic bibliography generation Help

Assignee:

HITACHI METALS LTD (JP)
KATAOKA KOUTA (JP)
NAKANO YOUSUKE (JP)

International Classes:

C22C38/00; C22C38/18; C22C38/52

Foreign References:

JP2007224418A	2007-09-06
JP2004018925A	2004-01-22
JP2004100027A	2004-04-02
JP2003155540A	2003-05-30
JP2007224418A	2007-09-06

Other References: