Duplex 2101

2101 is a duplex (austenitic-ferritic) stainless steel with relatively low contents of alloying elements. It has high mechanical strength than austenitic stainless steels. Its good corrosion resistance is on par with that of most standard stainless steel grades. Combined these properties, 2101 can be utilized to optimize design with respect to strength, maintenance, durability and long-term cost efficiency.

Chemical Composition (wt. %)

	UNS No.	Ni	Cr	C	Fe	Mn	Si	N	Mo	Others
min.	S32101	1.35	21.0	-	Bla.	4.0	-	0.20	0.1	Cu 0.10-0.80
max.	S32101	1.70	22.0	0.04	Bla.	6.0	1.0	0.25	0.8	Cu 0.10-0.80

Main Features

High strength, approximately twice as high proof strength as austenitic stainless steels ASTM 304 and 316.
Very good resistance to stress corrosion cracking.
Good resistance to general corrosion and pitting.
High energy absorption.
Physical properties that offer design advantages.
Ease of fabrication and good toughness.
Very good weldability.

Main Applications

Pulp & paper plant equipment.
chemical process pressure vessels, piping, storage tanks and heat
exchangers.
Waste water handle systems.
Mixers and agitators.

Fabrication and Heat Treatment

2101 can be readily formed using various cold and hot working processes.
Details to see “FABRICATION INSTRUCTIONS FOR HIGH-ALLOYED AUSTENITIC STEELS AND NICKEL ALLOYS”

Welding

2101 generally have good weldability and can be welded using most of the welding methods used for austenitic stainless steel: SMAW, GTAW, GMAW, FCW, PAW, SAW, Laser welding, Resistance welding and High frequency welding.

Duplex 2205

Duplex 2205 is a two-phase, ferritic, austenitic chromium–molybdenum–nickel alloyed stainless steel. It is the most widely used duplex stainless steel grade and is characterized by high yield strength, double that of the standard austenitic stainless steel grades. It also demonstrates good fatigue strength, as well as outstanding resistance to stress corrosion cracking, crevice, pitting, erosion, and general corrosion in severe environments.

Chemical Composition (w.%)

	UNS No.	Ni	Cr	C	Fe	Mn	N	Mo	Others
min.	S32205	4.50	22.0	-	Bla.	-	0.14	3.0
max.	S32205	6.50	23.0	0.03	Bla.	2.0	0.20	3.5

Main Features

High resistance to chloride stress corrosion cracking
Chloride pitting and crevice corrosion resistance superior to 317L stainless
Good general corrosion resistance
High strength
Good sulfide stress corrosion resistance
Useful up to 600°F

Main Applications

Chemical process vessels, piping, and heat exchangers
FGD scrubber systems
Pulp mill digesters, bleach washers, chip pre-steaming vessels
Food process equipment
Oil field piping, heat exchangers

Fabrication and Heat Treatment

2205 can be readily formed using various cold and hot working processes.
Details to see “FABRICATION INSTRUCTIONS FOR HIGH-ALLOYED AUSTENITIC STEELS AND NICKEL ALLOYS”

Welding

2205 generally have good weldability and can be welded using most of the welding methods used for austenitic stainless steel: SMAW, GTAW, GMAW, FCW, PAW, SAW, Laser welding, Resistance welding and High frequency welding.

Duplex 2304

2304 is a molybdenum-free duplex stainless steel whose structure is a balance of ferritic and austenitic. It has general corrosion resistance similar or better than Alloys 304L and 316L, but with yield strength nearly double that of austenitic stainless steels.

Chemical Composition (wt. %)

	UNS No.	Ni	Cr	C	Fe	Mn	N	Mo	Others
min.	S32304	3.00	21.50	-	Bla.	-	0.05	0.05	Cu 0.05-0.60
max.	S32304	5.50	24.5	0.03	Bla.	2.50	0.20	0.60	Cu 0.05-0.60

Main Features

Good stress corrosion resistant properties compared to 304 and 316.
High resistance to stress corrosion cracking.
Suitable for applications in the -58oF to 572oF (-50oC to 300oC) temperature range.
High mechanical strength and good fatigue properties.
Good weldability and easy fabrication.

Main Applications

Chloride containing environments.
Pulp and paper industry.
Desalination plants.
In chemical industry, can be used as cargo tanks and pipe systems.
Pressure vessels.
Heat exchangers.
Water heaters.
Rotors, impellers and shafts.

Fabrication and Heat Treatment

2304 can be readily formed using various cold and hot working processes.
Details to see “FABRICATION INSTRUCTIONS FOR HIGH-ALLOYED AUSTENITIC STEELS AND NICKEL ALLOYS”

Welding

2304 generally have good weldability and can be welded using most of the welding methods used for austenitic stainless steel: SMAW, GTAW, GMAW, FCW, PAW, SAW, Laser welding, Resistance welding and High frequency welding.

Duplex 2507

2507 is a super duplex stainless steel with designed for demanding applications which require exceptional strength and corrosion resistance, such as chemical process, petrochemical, and seawater equipment. The steel has excellent resistance to chloride stress corrosion cracking, high thermal conductivity, and a low coefficient of thermal expansion. The high chromium, molybdenum, and nitrogen levels provide excellent resistance to pitting, crevice, and general corrosion.

Chemical Composition (wt. %)

	UNS No.	Ni	Cr	C	Fe	Mn	N	Mo	Others
min.	S32750	6.0	24.0	-	Bla.	-	0.24	3.0
max.	S32750	8.0	26.0	0.030	Bla.	1.20	0.32	5.0

Main Features

High strength.
Good to very good resistance to pitting and crevice corrosion.
High resistance to stress corrosion cracking and corrosion fatigue.
Good to very good resistance to uniform corrosion.
Good erosion resistance.
Good weldability.

Main Applications

Oil and gas industry: offshore platforms, heat exchangers, process and service water systems, fir-fighting systems, injection and ballast water systems.
Chemical process industry: heat exchangers, vessels, and piping.
Desalination plants: high pressure RO-plant and seawater piping.
Mechanical and structure components: high strength, corrosion resistant parts.
FGD systems: scrubber systems, absorber towers, ducting, and piping.

Fabrication and Heat Treatment

2507 can be readily formed using various cold and hot working processes.
Details to see “FABRICATION INSTRUCTIONS FOR HIGH-ALLOYED AUSTENITIC STEELS AND NICKEL ALLOYS”

Welding

2507 generally have good weldability and can be welded using most of the welding methods used for austenitic stainless steel: SMAW, GTAW, GMAW, FCW, PAW, SAW, Laser welding, Resistance welding and High frequency welding.