Page 2 - SD 2507

Impact strength (KV typical values)
CORROSION
RESISTANCE -50°C -20°C 0°C 20°C
KV plates (guaranteed) (-58°F) (-4°F) (32°F) (68°F)
> 90 J
> 95 J
> 70 J
> 85 J
KV weld metal (typical) > 30 J > 40 J > 50 J > 55 J

Impact values of welds are closely related to the microstructure ( /  balance) and
the control of chemical analysis (oxygen, nitrogen, nickel) depend on welding
processes and parameters. The best results are obtained for high austenite
contents (75-60 %) and low oxygen levels. High nitrogen contents associated with
high ferrite levels must be avoided. For more information, please contact us.

Hardness values - Typical values
HV 5 : 250 to 280 HRC < 28

PHYSICAL Density : 7,820 kg/m - 0.28 lb/in
3
3
PROPERTIES
Interval Thermal °C °F Resistivity Thermal Specific modulus modulus
Shear
Young
heat
Temper expansion (µ cm) conductivity (J.kg .K ) (GPa) (GPa)
G
E
-1
-1
-1
-6
-1
-1
x10 K
(W.m .K )
°C
20-200 13.5 20 68 85 17 450 200 75
14
95
20-300 14.5 100 392 100 18 500 190 73
530
20-500
70
19
392
180
200

STRUCTURE 25 Cr super duplex grades are subject to intermetallic phase precipitations ( , ...)
STABILITY particularly when improperly heat treated. Higher molybdenum and tungsten
additions increase the sensitivity to sigma phase transformation. CLI equipments
and heat treatments are optimised in order to control the composition, structure
and properties of the products. The microstructure free of intermetallic phases
contributes to an increase of both toughness properties and corrosion resistance
properties.

Nitrogen additions have been increased compared to the former 25 Cr super-
duplex grade (0.18%  0.25%) in order to increase both corrosion resistance
properties and structure stability, particularly in HAZ.

UR 35 N UR 45 N UR 52 N UR 52 N +
UR 47N + UNS S32760 DTS 25 NWCu Mo, W, Si
°C °F
1000°C • M7 C3 carbide, Cr N nitride HAZ
1000 1830 1800°F •  phase
Cr • Cr 2 N nitride
800 1470 Mo •  phase
W •  2 phase
600 1110 Si • M 23 C 6 carbide
• R Phase
400 750
•  phase
200 390 •  phase (Cu)
Cr, Mo, Cu, W • ' phase
time • G. phase...
10 100 1000 10000 (sec.) 300°C
600°F
Cr, Mo, Cu, W
0.1 1 10 100 hour Time

Possible precipitations in super duplex stainless steels

Heat treatment :
SD 2507 is delivered in the solution annealed and water quenched conditions
(1080/1120°C - 1976/2018°F). The chemical analysis and heat treatment are
optimised in order to reach nearly a 50%  / 50%  microstructure.