Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
HEAT-RESISTANT AUSTENITIC STAINLESS STEEL EXCELLENT IN SCALE EXFOLIATION RESISTANCE, AND STAINLESS STEEL PIPE
Document Type and Number:
Japanese Patent JP2013133533
Kind Code:
A
Abstract:

To provide: austenitic stainless steel which is applied for a steel pipe having an inner face subjected to shot peening treatment among heat exchanger pipes used in a thermal power generation facility and has improved scale exfoliation resistance of the inner face; and a stainless steel pipe comprising the stainless steel.

The heat-resistant austenitic stainless steel includes, by mass, 0.02-0.2% of C, 0.1-1.5% of Si, 0.1-3% of Mn, 7-13% of Ni, 16-20% of Cr, 0.4-4% of Cu, 0.05-0.6% of Nb, 0.05-0.6% of Ti, 0.05-0.35% of Zr, 0.005-0.1% of Ce, 0.0005-0.005% of B, 0.001-0.15% of N, 0.005% or less (excluding 0%) of S and 0.05% or less (excluding 0%) of P, respectively, with the balance of iron with inevitable impurities. In the heat-resistant austenitic stainless steel, a ratio (HV1/HV0) between an average hardness (HV1) of the area ranging from the surface to a depth of 50 μm in the thickness direction and an average hardness (HV0) of the center part in the thickness direction is 1.20 or more.


Inventors:
MIYAMURA TAKEO
NANBA SHIGENOBU
Application Number:
JP2011286431A
Publication Date:
July 08, 2013
Filing Date:
December 27, 2011
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
KOBE STEEL LTD
International Classes:
C22C38/00; C22C38/58; C21D7/06
Domestic Patent References:
JPH06322489A1994-11-22
JP2006307313A2006-11-09
JP5143960B12013-02-13
Foreign References:
WO2011155296A12011-12-15
Attorney, Agent or Firm:
Kyuichi Ueki
Hisahiko Ueki
Tadashi Sugakawa
Hiroaki Ito