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FERRALIUM® 255 SD50

FERRALIUM^® 255-SD50

Ferralium 255 SD50 sets a new bench mark for Super Duplex as the first to state 570N/mm2 as the minimum 0.2% Proof Stress. It offers excellent corrosion resistance in a wide variety of corrosive chemicals including sulphuric, phosphoric and nitric acids.

In Seawater and other chloride containing environments Ferralium 255 SD50 also provides outstanding resistance to pitting and crevice corrosion, with Critical Pitting Temperature exceeding 50°C.

Excellent ductility and impact strength at both ambient and sub-zero temperatures combine with a high resistance to abrasion, erosion and cavitation erosion.

Listed in NACE MR 01 75 for sour service and having gained ASME Approval for Pressure Vessel applications, Ferralium 255-SD50 is tested to the highest degree using tests designed to guarantee that the trade-marked product possesses high integrity, a correct phase balance and the absence of sigma and other deleterious phases.

Ferralium 255 SD50 is particularly applicable for large forgings, as the formation of sigma phase is much less likely than it is for other Super Duplexes.

Alloy	Common Name	Related Specifications			Tensile Strength	Proof Stress	Elongation
Alloy	Common Name	British	European	United States	Tensile Strength	Proof Stress	Elongation
Super Duplex FERRALIUM 255-SD50	Alloy 255 High Strength	1.4507	UNS S32550	F61	790[114.5]	600 [87]	25

FERRALIUM^® 255-SD50 Technical Information

FERRALIUM 255-SD50 Bar stock sizes available
Diameter (in)	Diameter (mm)	kg per m
1⁄2	12.7	0.98
5⁄8	15.88	1.54
3⁄4	19.05	2.23
7⁄8	22.23	3.02
1	25.4	3.97
1 1⁄8	28.58	5.02
1 1⁄4	31.75	6.17
1 3⁄8	35.05	7.54
1 1⁄2	38.10	8.89
1 5⁄8	41.40	10.53
1 3⁄4	44.45	12.10
1 7⁄8	47.75	13.97
2	50.80	15.84
2 1/4	57.15	20.04
2 1/2	63.50	24.73
2 3/4	69.85	29.91
3	76.20	35.62
3 1/4	82.55	41.79
3 1/2	88.90	48.48
3 3/4	95.25	55.63
4	101.60	63.30
4 1/4	107.60	71.47
4 1/2	114.30	80.13
4 3/4	120.65	89.28
5	127.00	98.92
5 1/4	133.35	108.90
5 1/2	139.70	119.69
6	152.40	142.45
6 1/2	165.10	167.18
6 3/4	171.45	180.40
7	177.80	193.88
7 1/2	190.05	221.40
8	203.20	253.22
9	228.60	320.46
10	254.00	395.63
12	304.80	569.70
14	355.60	775.46

Specifications of Ferralium 255-SD50

FERRALIUM to MSA-MPS-51VS-SD50-BAR
FERRALIUM to MSA-MPS-51VS-SD50-PLATE
NORSOK MDS D57 Bar
NORSOK MDS D55 Plate
EN 10088-1 1.4507
ASTM A182 Grade F61 UNS S32550 Forged Flanges
ASTM A240 UNS S32550 Sheet and Plate
ASTM A240 UNS S32520 Sheet and Plate
ASTM A479 UNS S32550 Bar
ASTM A276 UNS S32550 Condition A
ASME Approval as Table UHA 23 and Code Case 1883
NACE MR 01-75

Downloads
Purchase Specifications >
FERRALIUM SD50 Bar Purchase Specification FERRALIUM SD50 Plate Purchase Specification FERRALIUM SD50 Weld Wire Specification

Brochures >
FERRALIUM Brochure

Past Papers >
The Influence of Copper on the Pitting Corrosion of Duplex Stainless Steels UNS S32550 L F Garfias-Mesias J M Sykes and C D S Tuck Corrosion Vol 54 No 1 1998 p 40

Technical Data Sheets >
Machining FERRALIUM 255 [SD50] Welding FERRALIUM 255-SD50 FERRALIUM 255-SD50 ASME IX Weld Qualification

Chemical Specification of Ferralium 255-SD50

Elements	C	Cr	Cu	Fe	Mo	Mn	N	Ni	P	S	Si
Minimum		24.50	1.50	REMAINDER	3.10	0.80	0.20	5.50			0.20
Maximum	0.030	26.50	2.00		3.80	1.20	0.25	6.50	0.025	0.005	0.70

Basic Properties of Ferralium 255-SD50 - Mechanical Properties

Bar - Ruling Sections up to and including 101.6mm (4")
0.2% Proof Stress (N/mm²) [ksi] minimum	600 [87]
Ultimate Tensile Strength (N/mm²) [ksi] minimum	790 [114.6]
Elongation (%) minimum	25
Hardness (HBN)	270max
Charpy V-notch Impact at ambient Temp (J) [ft.lb]	80min [59min]
Charpy V-notch Impact at -46°C (J) [ft.lb]	45av, 35min [33av, 25.8min]

Ruling Sections over 101.6mm (4") and Plate (all section sizes)
0.2% Proof Stress (N/mm²) [ksi] minimum	570 [82.6]
Ultimate Tensile Strength (N/mm²) [ksi] minimum	790 [114.6]
Elongation (%) minimum	25
Hardness (HBN)	270max
Charpy V-notch Impact at ambient Temp (J) [ft.lb]	80min [59min]
Charpy V-notch Impact at -46°C (J) [ft.lb]	45av, 35min [33av, 25.8min]

Additional Testing
ASTM G48A Corrosion test at 50°C	No pitting and weight loss <0.8g/m²
Ultrasonic Testing	According to ASTM A388
Ferrite Content	35%-55%
Microstructure	Microstructure certified free from grain boundary carbides, sigma, chi and laves phases.

Physical Properties of Ferralium 255-SD50

Applications of Ferralium 255-SD50

Chemical Process Industry:

Sulphuric Acid Production, Nitric Acid Processes, Polypropylene Production, PVC ProductionTitanium Dioxide Production, Caustic Evaporators, Equipment Handling Organic and Fatty Acids

Marine Industry and Shipbuilding:

Propellers and Shafts, Rudders, Shaft Seals, Pumps, Bolts and Fasteners, Valves, Instrumentation, Oil and Chemical Tankers

Oil and Gas Industry:

Pumps, Valves, Pipe, Vessels, Wellhead Equipment, Subsea Equipment

Pollution Control:

Fans and pumps, Wet Scrubbers, Incinerators

Copper Smelting:

ID Fans, Tuyere bars, Wet Scrubbers, Leaching Area Precipitators

Pulp and Paper Industry:

Black liquor heater tubes, Digester Blow Valves, Rotary Feed Valves, I.D.Fans, Brownstock Washers, Precipitators, Bleaching Components

Food Industry:

Sugar Cane Centrifuges, Corn and Vegetable processing plant

Agrochemicals:

Fertilizer Production (Wet phosphoric acid)

Civil Engineering:

Statue of Liberty supporting structure, Swimming Pools, Sewage Treatment

Ferralium 255-SD50 Features

Forms of Ferralium 255-SD50 Available

Machining Advice of Ferralium 255-SD50 - Hot worked, precipitation hardened alloy

Operation	Cutting Speed m/min (ft/min)	Feed Rate mm/rev (in/rev)	Depth of cut mm(in)
Milling	40 (130)	0.05-0.13 mm/tooth 0.02-0.005 in/tooth	0.5-6.0 (0.02-0.25)
Drilling – 6.4mm (1/4”) dia	250rpm	0.075 (0.003)
Drilling – 12.7mm (1/2”) dia	250rpm	0.125 (0.005)
Drilling – 25.4mm (1”) dia	150rpm	0.28 (0.011)
Turning - Roughing	30-45 (100-150)	0.20 – 0.38 (0.008-0.015)	3 (0.125)
Turning - Finishing	50-60 (165-200)	0.13 – 0.20 (0.005-0.008)	0.5 (0.02)
Tooling	Milling/Turning: Carbide (SANDVIK GC 235, SECO T25M) Drilling: HSS, point angle 118°, chisel angle 120°

Alloy Comparisons

Alloy Comparisons	S17400 (17- 4PH)	S32205	718	S31254	FERRALIUM 255-SD50
0.2% Proof Strength (N/mm²)	1100	510	500	325	630
Corrosion Rate (mm.y^-1) Seawater	~1	<0.01	<0.01	<0.01	<0.01
Corrosion Rate (mm.y^-1) 10% sulphuric acid at 80°C	10	0.4	<0.15	1.5	<0.15
Corrosion Rate (mm.y^-1) Boiling 50% nitric acid	<0.15	<0.15	<0.15	0.4	<0.15
Wear Properties related to Hardness (HRC), typical	RC38	RC25	RC20	RC20	RC28

Disclaimer
Data in this Ferralium 255-SD50 page is provided solely for the purposes of distribution of information. Langley Alloys cannot make guarantees with respect to subject matter or accuracy of this information. Langley Alloys specifically disclaims all guarantees, expressed, implied or otherwise, including without limitation, all warranties of merchantability and fitness for a particular purpose. This publication may include technical inaccuracies or typographical errors. If errors are found, please make a notification via e-mail to: info@langleyalloys.com

Density (Kg.m^-1)	78.1
Magnetic Permeability	33
Young’s Modulus (N/mm²)	199 x 10³
Specific Heat, 20°C (J.Kg^-1.°K^-1)	475
Fracture Toughness, K_Q (MPa.m^½)	98
Specific Electrical Resistance, 20°C (µO.m)	0.80
Thermal conductivity, 20°C (W.m^-1.°K^-1)	14.2
Mean coefficient of thermal expansion, 20-100°C (°K^-1)	11.1 x 10^-6

Alloys	Bars & Sections	Hot & Cold Rolled Plate	Ingot & Billet	Forged Products	Sand Castings
FERRALIUM 255-SD50
FERRALIUM 255-SD40
FERRALIUM 255-3SF
FERRALIUM 255-3AF
FERRALIUM 255-3SC
FERRALIUM 255-FG46
ALLOY 2507
ALLOY S32760

FERRALIUM® 255-SD50

FERRALIUM® 255-SD50 Technical Information

FERRALIUM^® 255-SD50

FERRALIUM^® 255-SD50 Technical Information