JP2006519313A5

JP2006519313A5 -

Info

Publication number: JP2006519313A5
Application number: JP2006507921A
Authority: JP
Filing date: 2004-02-19
Publication date: 2007-01-25

Claims

% By weight
C: exceeding 0 and maximum 0.03%
Si: Max 0.5%
Mn: 0 to 3.0%
Cr: 24.0 to 30.0%
Ni: 4.9 to 10.0%
Mo: 3.0-5.0%
N: 0.28 to 0.5%
B: 0 to 0.0030%
S: Maximum 0.010%
Co: 0 to 3.5%
W: 0 to 3.0%
Cu: 0 to 2.0%
Ru: 0 to 0.3%
Al: 0 to 0.03%
Ca: 0 to 0.010%
The chemical composition of the present invention, the balance consisting of normal impurities, additives and Fe, and the ferrite content is 40 to 65 vol%, and the formula PRE =% Cr + 3.3% Mo + 16% N Greater than 46, PRE in the austenite and ferrite phases is greater than 45, the yield point of the steel at a tensile Rp _0.2 is greater than 720 N / mm ² , and CPT> 90 ° C. and CCT Ferritic / austenitic duplex stainless steel with ≧ 60 ° C.

The steel according to claim 1, wherein the chromium content is 26.5 to 29.0 wt%.

The steel according to claim 1 or 2, wherein the manganese content is 0.5 to 1.2 wt%.

The steel according to any one of claims 1 to 3, wherein the nickel content is 5.0 to 8.0 wt%.

The steel according to any one of claims 1 to 4, wherein the molybdenum content is 3.6 to 4.9 wt%.

The steel according to any one of claims 1 to 5, wherein the nitrogen content is 0.35 to 0.45 wt%.

Steel according to any one of claims 1 to 6, characterized in that the content of the ruthenium is in many 0.3 wt% or in more than 0.

The steel according to any one of claims 1 to 7, wherein the cobalt content is 0.5 to 3.5 wt% .

The steel according to any one of claims 1 to 8, wherein the copper content is 0.5 to 2.0 wt% .

The steel according to any one of claims 1 to 9, wherein a content of the ferrite is 42 to 46 vol% .

% Is wt%, and PRE =% Cr + 3.3% Mo + 16N and PREW =% Cr + 3.3 (% Mo + 0.5% W) + 16N, the PRE value or PREW value of the steel as a whole is more than 46, The steel according to any one of claims 1 to 9.

The steel according to claim 11, wherein the PRE value and the PREW value of both the ferrite phase and the austenite phase are larger than 45, and the PRE value and the PREW value of the whole steel are larger than 46. .

The steel according to claim 1, wherein the steel is used as a supply cord pipe in an environment containing chloride, particularly in a seawater environment .

14. Steel according to any one of claims 1 to 13 for the manufacture of pipes, welding materials and structural parts such as flanges and joints, such as rods, welded pipes and non-welded pipes .