Title:
CONTINUOUS CASTING METHOD FOR CASTING PIECE FOR STEEL PIPE
Document Type and Number:
Japanese Patent JP2017080765
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a method for restraining formation of an embrittlement phase when continuously producing a highly corrosion-resistant duplex stainless steel.SOLUTION: When continuously casting an alloy comprising, by mass%, 0.03% or less C, 0.4% or less Si, 3.0% or less Mn, 0.04% or less P, 0.008% or less S, 0.2-2.0% Cu, 5.0-7.0% Ni, 23-30% Cr, 2.5-5.0% Mo, 1.5-4.0% W, 0.24-0.40% N, 0.030% or less Al, and 10-300 ppm by mass, a relation between a ratio I/Iof the deposition amounts Iand I of intermetallic compound at a center of cross-section of the casting piece in such a case that Bi is not contained and in a case contained and an average Md value of the alloy defined by ΣX×(Md)[eV] (Xis the atomic fraction of an alloy component i; and (Md)is the Md value [eV] of the alloy component i), and a relation between the average Md value of the alloy and included Bi amount are determined, and such a Bi content that the average Md value of the alloy is 0.97 or less and the ratio I/Igets to 0.70 or less is provided.SELECTED DRAWING: Figure 4
Inventors:
YAMASHITA YUI
MIZUKAMI HIDEO
MIZUKAMI HIDEO
Application Number:
JP2015210819A
Publication Date:
May 18, 2017
Filing Date:
October 27, 2015
Export Citation:
Assignee:
NIPPON STEEL & SUMITOMO METAL CORP
International Classes:
B22D11/00; B22D11/108; B22D11/115; C21C7/00; C21C7/04; C22C38/00; C22C38/58
Domestic Patent References:
| JP2015196192A | 2015-11-09 | |||
| JP2015196193A | 2015-11-09 | |||
| JP2015196183A | 2015-11-09 |
Attorney, Agent or Firm:
Tetsuya Mizogami
Susumu Yamamoto
Susumu Yamamoto