|
|
| Mailing Address |
 |
UKF Stainless Ltd
12 Buntsford Park Road
Bromsgrove
Worcestershire
B60 3DX
|
|
| Telephone / Fax |
|
| Tel: |
01527 578686 |
| Fax: |
01527 837792 |
|
|
| Email |
|
 info@ukfstainless.co.uk |
|
|
|
 |
 |
1.4501
|
|
|
Introduction:
A 'super' duplex steel with PREN about 41.
Duplex steels combine high strength with corrosion
resistance. Their resistance to stress-corrosion cracking
in neutral chlorides is superior to that of the 18/10
and 18/12/3 austenites. In high chloride acidic or
moderately sour environments where hydrogen or sulphide
stress cracking is more likely, higher alloyed austenitics
need also to be considered.
Exposure to moderate and high temperatures and less
rapid cooling may cause embrittlement.
Impact values are high at room temperature with transition
temperatures of base material below -50°C. However,
the proportion and orientation of ferrite in welds
and base material may affect toughness at subzero
temperatures.
Metallurgy:
When ferrite forming elements (Cr,Mo,Si,Nb) are kept
at high levels but austenite promoting elements (Ni,Mn,N,C)
are reduced, stainless steels with a mixed or duplex
microstructure are produced. Mixtures of 40-60% of
either phase are near optimum.
Careful control of both the compositions and cooling
rate from high temperatures is necessary to prevent
the steel or weldment containing large amounts of
ferrite and/or traces of sigma phase that both embrittle
and impair corrosion resistance. Welding requires
control of heat-input and thermal cycles plus use
of special
consumables enriched with nitrogen and/or nickel.
Duplex stainless steels may suffer severe embrittlement
due to sigma phase formation in the 550-900°C
range and from alpha prime in the 280-550°C range.
The period for embrittlement may be short or long
depending on composition, time, temperature and cold
work.
Composition:
| Element |
Minimum
(%) |
Maximum
(%) |
| Chromium |
24.00 |
26.00 |
| Nickel |
6.00 |
8.00 |
| Molybdenum |
3.00 |
5.00 |
| Nitrogen |
0.20 |
0.30 |
| Manganese |
- |
1.00 |
| Carbon |
- |
0.03 |
| Copper |
0.50 |
1.00 |
| Tungsten |
0.50 |
1.00 |
|
Similiar Specifications:
EURONORM X2 CrNiMoCuWN
25 7 4 (1.4501)
24-26%Cr, 6-8%Ni, 3-4%Mo,
0.20-0.30%N, <1.0%Mn, <0.03%C, 0.5-1.0%Cu, 0.5-1.0%W
ASTM UNS S32760
24-26%Cr, 6-8%Ni, 3-4%Mo,
0.20-0.30%N, <1.0%Mn, <0.03%C, 0.5-1.0%Cu, 0.5-1.0%W
Applications:
X2 CrNiMoCuWN 25 7 4 / S32760
/ S39276 is a long-established steel used in wrought
and cast forms
for:
Offshore equipment
- pumps, valves, piping, heat exchangers handling
seawater or production
streams.
Product Forms:
Bar & long products
ASTM UNS S32760
276
Forgings & others
ASTM UNS S32760
182, 815, 473, 314
Tube and/or pipe
ASTM UNS S32760
790
|
|
|
Page Last Modified: 7/04/06 17:21
|
|
|
|
|
