Chintamani Stainless Inc is a well-established venture that is manufacturing, exporting and supplying Super Duplex Steel Fasteners from the last many years. Providing the best and innovative product to the customer is our first priority. We offer our product to both national and international customers. To design a global standard product we acquire the finest quality of raw material for the manufacturing and also equipped the most advanced technology and tools to bring out accuracy and end finish in the product. To keep in mind customer’s requirement and needs we cater our product in custom made shapes, size, length, and thickness at quite a reasonable rate.

Super Duplex Steel Fasteners are mixed microstructure of ferrite and austenite that are used in those applications where exceptional corrosion resistance and strength is required. These include molybdenum, nitrogen and chromium content that provides great resistance to crevice corrosion and chloride pitting attacks. These are generally used in aggressive environments such as warm chlorinated water, chloride containing media. These grade of fastener ensure good resistance to erosion and abrasion. Furthermore, they offer superior resistance to uniform and local corrosion at soaring temperatures. These fasteners offer superior services in severe atmospheric conditions such as marine and offshore applications. These range of fasteners features low thermal expansion and fatigue resistance in high energy absorption. In addition to it has good mechanical strength and ensures good weldability.

Super duplex 2507 bolts offer a variety of valuable features and applications. These super-strong bolts are designed to withstand high pressure and temperature, making them ideal for environments where these factors are a concern. They also have higher corrosion resistance, making them perfect for operations where contact with seawater or other corrosive substances is likely. Furthermore, super duplex 2507 bolts can be used in the most challenging environments due to their superior strength, making them perfect candidates for offshore and oilfield operations. All in all, super duplex 2507 bolts provide an excellent combination of strength, durability and corrosion resistance, perfect for any function that demands a dependably robust fastener.

Super duplex 1.4410 fasteners are becoming increasingly popular as a fastening solution due to their enormous strength and excellent corrosion resistance. These fasteners are available in various shapes and sizes, including screws, bolts, nuts, washers, rivets and anchors. They have high fatigue strength and superb hot corrosion resistance properties. Furthermore, super duplex 1.4410 fasteners have super-austenitic stainless steel characteristics, making them an ideal choice when exposed to hostile environments. As a result of their increased popularity, they are widely used in various industries such as mining and oil & gas exploration and production.

Specification

Specifications of Super Duplex 2507 Fasteners	ASTM / ASME F53, A479 / SA479
Standard of Super Duplex 2507 Fasteners	DIN, ASTM, BS and all International Standards
Length of Super Duplex 2507 Fasteners	3 mm to 200 mm
Super Duplex 2507 Nuts Size	M3 - M56 | 3/6" to 2" | Custom Sizes
Super Duplex 2507 Bolt / Screw Size	M3 - M56 | 3/6" to 2" | Custom Sizes
Super Duplex 2507 Machine Screws Size	M1.6 - M12
Super Duplex 2507 Washers Size	M3 - M56 | 3/6" to 2" | Custom Sizes
Super Duplex Steel Grades	Super Duplex Steel UNS S32750
Super Duplex 2507 Fasteners Type	Socket Head Cap Screw, Wing Screw, T-Head Bolts, Foundation Bolts,Screw, Studs, Socket Screw, Hex Set Screw, Cap Screw, Machine Screw, Wing Screw, Spring Washers, Eye Bolt,Structural Bolts, Bolts, Nuts, Sockets, Screws, Allen Cap screw, Washers, Studs, Marine Anchors, Anchors, Hexagon Nut,U- Bolts, Anchor Bolt, Nut, Hex Coupling Nut, Hex Nut, Square Nut, Hex Domed Cap Nuts, Hex Head Bolts, Stud Bolts, Socket Hexagon Head Screw, Pan Head Screw, Mushroom Head Square Neck Bolts, J Bolts

CHEMICAL COMPOSITION

Element	Content (%)
Chromium, Cr	24 – 26
Nickel, Ni	6 – 8
Molybdenum, Mo	3 – 5
Manganese, Mn	1.20 max
Silicon, Si	0.80 max
Copper, Cu	0.50 max
Nitrogen, N	0.24 – 0.32
Phosphorous, P	0.035 max
Carbon, C	0.030 max
Sulfur, S	0.020 max
Iron, Fe	Balance

MECHANICAL PROPERTIES

Grade	Tensile Strength (MPa) min	Yield Strength 0.2% Proof (MPa) min	Elongation (% in 50mm)	Hardness Rockwell C (HR C)
UNS-S 32750	795	550	15	32max

ASTM F53 Super Duplex Steel 2507 Fasteners Equivalent Grade

Alloy	Common Name	Related Specification
		European	UNS	ASTM/ASME
Alloy 2507	SAF 2507 ®	1.4410	UNS S32750	A479 / SA479 / F53

Super Duplex Stud Bolts Application

• Petrochemicals
• Aircraft Exhaust Manifolds
• Off-Shore Oil Drilling Companies
• Sea Water Equipment
• Pharmaceuticals
• Power Generation

General characteristics

Steel designations

Performance

Typical chemical composition, % by mass

name

EN

ASTM Type

UNS

PRE

A1) %

Rp0.2 MPa

Grade family

C

Cr

Ni

Mo

N

2507

1.4410

2507

S32750

43

20

550

D

0.02

25.0

7.0

4.0

0.27

2205 stainless steel grades	Industry Specifications	UNS
Duplex 2507 2507 (EN 1.4410/UNS S32750) A super duplex product with higher corrosion resistance and mechanical strength than Forta DX 2205. Often used in extremely corrosive environments.	• Desalination plants • Industrial piping • Scrubbers • Oil and gas industry, typically tubular products, flanges,fittings and valves • Deep-sea pipelines	• Cold rolled coil and sheet • Hot rolled coil and sheet • Quarto plate • Bar • Wire rod • Semi-finished (bloom, billet, ingot & slab)
Duplex 32760 100 (EN 1.4501/UNS S32760) A super duplex product with higher corrosion resistance and mechanical strength than Forta DX 2205. Often used in extremely corrosive environments.	• Desalination plants • Industrial piping • Scrubbers • Oil and gas industry, typically tubular products, flanges, fittings and valves • Deep-sea pipelines	• Cold rolled coil and sheet • Hot rolled coil and sheet • Quarto plate • Bar • Wire rod • Semi-finished (bloom, billet, ingot & slab)

Performance

Elongation vs. corrosion resistance.

Elongation vs. Corrosion resistance

Strength vs. Corrosion resistance

Elongation vs. Corrosion resistance

Duplex stainless steels, known for their high chromium content, provide excellent corrosion resistance, particularly in uniform corrosion environments with rates below 0.1 mm/year. Forta DX 2205 shows superior resistance to chloride-contaminated sulfuric acid compared to traditional stainless steels like Supra 316L/4404, approaching the performance of Ultra 904L. In dilute hydrochloric acid, Forta SDX 2507 and similar high-alloyed duplex steels are suitable, though localized corrosion risks exist around crevices even within safe usage limits.

Corrosion resistance

• Uniform Corrosion: Due to high chromium content, these steels resist uniform corrosion well, typically less than 0.1 mm/year.
• Sulfuric Acid: DX 2205 shows superior resistance in sulfuric acid contaminated by chloride ions compared to Supra 316L/4404.
• Hydrochloric Acid: SDX 2507 and DX 2205 can be used in dilute hydrochloric acid, with potential risks of localized corrosion in crevices.
• Nitric Acid: LDX 2101 and DX 2304, with their high chromium content and low molybdenum, are suitable for environments where resistance to strongly oxidizing nitric acid is needed.

PRE values for Forta Duplex grades and some austenitic grades

Steel designations				PRE
name	EN	ASTM Type	UNS
2205	1.4462	2205	S32205	35
2507	1.4410	2507	S32750	43

Results from stress corrosion cracking immersion tests in chloride solutions

name	ASTM G123		ASTM G36
	25% NaCl, pH 1.5, 106°C (b.p.), 1,000 h	40% CaCl2, 100°C, 500 h	45% MgCl2, 155°C (b.p.), 24 h
	U-bend samples	4-PB samples (90% of Rp0.2)	U-bend samples
2205	No SCC	No SCC	SCC
2507	No SCC	No SCC	SCC

Mechanical properties according to EN 10088 and EN 10028

	EN	ASTM	Product form	Yield strength	Tensile	Elongation	Elongation
name		UNS		Rp0.2[MPa]	strength	A[%]	A80[%]
				Rm[MPa]
2507	1.4410	S32750	Cold rolled coil (C)	550	750–1000	20	20
			Hot rolled coil (H)	530	750–1000	20	20
			Quarto plate (P)	530	730–930	20	20
			Bar	530	730–930	25	–
	1.4510	S32760	Cold rolled coil (C)	550	750–1000	20	20
			Hot rolled coil (H)	530	750–1000	25	25
			Quarto plate (P)	530	730–930	25	25

Mechanical properties according to ASTM A240

	EN	ASTM	Product form	Yield	Yield	Tensile	Tensile	Elongation
name		UNS		strength	strength	strength	strength	A50[%]
				Rp0.2[MPa]	Rp0.2 [ksi]	Rm [MPa]	Rm [ksi]
2507	1.4410	S32750	Plate, sheet and strip	550	80	795	116	15
100	1.4501	S32760	Plate, sheet and strip	550	80	750	108	25

Mechanical properties at elevated temperatures, minimum yield strength according to EN 10028-7

name	Strength		100°C	150°C	200°C	250°C
2507	Tensile strength	Rm [MPa]	680	660	640	630

Physical properties

Metric values according to EN 10088-1

name	EN	ASTM Type	UNS	Density [kg/dm3]	Modulus of elasticity at 20°C [GPa]	Coefficient of thermal expansion 20–100°C [10-6/K]	Thermal conductivity at 20°C [W/(m x K)]	Thermal capacity at 20°C [J/(kg x K)]	Electrical resistivity at 20°C [Ω x mm2/m]
2507	1.4410	2507	S32750	7.8	200	13.0	15	500	0.8
100	1.4410	-	S32760	7.8	200	13.0	15	500	0.8

Imperial values converted from Table 10

name	Density [lbm/in3]	Modulus of elasticity [psi]	Coefficient of thermal expansion 68–212°F [μin / (in x °F)]	Thermal conductivity [Btu/(hr x ft x °F)]	Thermal capacity [Btu/(lbm x °F)]	Electrical resistivity [μΩ x in]
2507	0.282	29 x 106	7.2	8.7	0.119	31.50

Fabrication

Duplex stainless steel is suitable for all forming processes used for stainless steel. The high yield strength compared to austenitic and ferritic stainless steel can however give differences in forming behavior. Depending on the chosen forming technique there could be consequences, such as increased springback. This point is particularly relevant to the forming of any high strength steel. Moreover, an excellent interplay between high yield strength, work hardening rate and elongation promote the duplex grades for light weight and cost-efficient applications with complex shapes. The impact of the high strength varies for different forming techniques. Common for all is that the estimated forming forces will be higher than for the corresponding austenitic and ferritic stainless steel grades. This effect will usually be lower than expected from just the increase in strength since the choice of duplex stainless steel is often associated with gauge reduction. It is important to consider that duplex stainless steel may also be more demanding on the tools and on the lubricant. This should also be noted when looking to down gauge.

Welding consumables

name	EN	ASTM Type	UNS	Consumable ISO designation
2507	1.4410	2507	S32750	25 9 4 NL

General characteristics

Steel designations

Performance

Typical chemical composition, % by mass

name

EN

ASTM Type

UNS

PRE

A1) %

Rp0.2 MPa

Grade family

C

Cr

Ni

Mo

N

2507

1.4410

2507

S32750

43

20

550

D

0.02

25.0

7.0

4.0

0.27