SAF 2205

Заготовки
SAF 2205

General description

Sandvik SANMAC SAF 2205™ is a duplex stainless steel (austenitic-ferritic). It is characterised by:

high resistance to stress corrosion cracking in chloride-bearing environments
high resistance to stress corrosion cracking in environments containing hydrogen sulphide
high resistance to general corrosion, pitting and crevice corrosion
high mechanical strength – roughly twice the proof strength of austenitic stainless steels excellent machinability
good hot-working properties
high resistance to erosion corrosion and corrosion fatigue
physical properties that offer design advantages
good weldability

Chemical composition (nominal) %

C max	Si max	Mn max	P max	S max	Cr	Ni	Mo	N
0.030	1.0	2.0	0.030	0.015	22	5.5	3.2	0.18

Standards

Sandvik Grade: SANMAC SAF 2205
ASTM: S31803
EN: 1.4462*
W Nr.: 1.4462
DIN: X 2 CrNiMoN 22 5 3
SS: 2377
* According to EN 10088, valid for sheet/plate, strip, semifinished products, bars, rods and sections for general purposes.

Product standards

Bars and shapes:	ASTM A479
	EN 10088-3*
	ASTM A276
Billets:	EN 10088-3*
	SEW 400

Certificate
Status according to EN 10204/3.1.B

Forms of supply

Bar and billet
Round bar is supplied in the solution annealed and quenched and peel-turned condition. The principal size range is 20 – 350 mm.
Billets, round as well as round-cornered square, are produced in sizes 80 – 350 mm.

Other products

Seamless tube and pipe
Welded tube and pipe
Fittings and flanges
Wire electrodes and filler wire/rods
Covered electrodes
Strip electrodes and flux for surfacing
Strip, annealed or cold-rolled to different degrees of hardness
Plate, sheet and wide strip
Forged products
Cast products

Mechanical properties

The following values apply to material in the solution annealed and quenched condition. Bar with sizes larger than 160 mm may have slightly lower values. More detailed formation can be supplied on request.

At 20°C (68°F)
Metric units

Proof strength R_p0.2^a) MPa min	R_p1.0^a) MPa min	Tensile strength, R_m MPa	Elong. A^b) % min	Hardness Brinell max.
450	500	660-860	25	270

Imperial units

Proof strength R_p0.2^a) ksi min	R_p1.0^a) ksi min	Tensile strength, R_m ksi	Elong. A^b) % min	Hardness Brinell max.
65	73	96-125	25	270

1 MPa = 1 N/mm²
a) R_p0.2 and R_p1.0 correspond to 0.2% offset and 1.0% offset yield strength respectively.
b) Based on L₀ = 5.65ÖS₀ , where L₀ is the original gauge length and S₀ the original cross-sectional area.

Figure 1. Comparision of proof strength, 0.2% offset, of SANMAC SAF 2205, high alloy austenitics and other grades, for material in the solution-annealed and quenched condition.

Impact strength
Sandvik SANMAC SAF 2205 possesses good impact strength both at room temperature and at low temperatures. Fig. 2 shows typical impact energy values for Sandvik SANMAC SAF 2205 bars in different sizes at -50°C (-58°F). The values apply for standard Charpy-V specimens (10 x 10 mm, 0.39 x 0.39 inch) taken in the longitudinal direction of the bar. For dimensions larger than 160 mm (6.3 inch) the impact strength is somewhat lower. Sandvik SANMAC SAF 2205 bar stock programme guarantees an impact strength of 70 J (52 ft lb) at -50°C (-58°F).

Figure 2. Typical impact stength values for SANMAC SAF 2205 bar at -50°C (-58°F).

At high temperatures
If Sandvik SANMAC SAF 2205 is exposed for prolonged periods to temperatures exceeding 280 °C (540 °F), the microstructure changes which results in a reduction in impact strength. This effect does not necessarily affect the behaviour of the material at the operating temperature. Contact Sandvik for advice. For pressure vessel applications, 280 °C (540 °F) is required as maximum.

Temp. °C	Proof Strength R_p0.2 MPa min.	Temp. °F	Proof Strength R_p0.2 ksi min.
100 150 200 250	360 335 315 300	200 300 400 500	52 49 46 44

Microstructure

In the solution annealed and quenched condition SANMAC SAF 2205 has an austenitic-ferritic microstructure, which is free from grain-boundary carbides and intermetallic phases. The ferrite content is 40 – 60%.

Physical properties

At 20°C (68°F), typical values
Density	7.8 g/cm³ , 0.28 lb/in³
Modulus of elasticity	200x10³ MPa, 29x10³ ksi
Specific heat capacity	480 J/kg °C, 0.11 Btu/lb°F
Thermal conductivity	14 W/m °C, 8 Btu/ft h°F
Thermal expansion at 30-100°C (86-212°F)	13 x10^-6/°C, 7.0 x10^-6/°F

Figure 3. Thermal expansion, per °C (30-100°C.)

SANMAC SAF 2205 has a for lower coefficient of thermal expansion than austenitic stainless steels and can therefore possess certain design advantages.

Corrosion resistance

Pitting and crevice corrosion
The pitting and crevice corrosion resistance of a steel is determined primarily by its chromium and molybdenum contents, but also by its nitrogen content as well as its slag composition and slag content. A parameter for comparing the resistance of different steels to pitting is the PRE number (Pitting Resistance Equivalent).

General corrosion
In most media, Sandvik SANMAC SAF 2205 possesses better resistance to general corrosion than steel of type AISI 316L and 317L. Impurities that increase corrosivity are often present in process solutions of acids. If there is a risk of active corrosion, higher-alloyed austenitic stainless steels should be chosen, e.g. Sandvik 2RK65 or Sandvik Sanicro28.

Figure 4. Critical pitting temperatures (CPT) for SANMAC SAF 2205. AISI 304 and AISI 316 at varying concentrations of sodium chloride (potentiostatic determination at +300 mV SCE), pH

6.0.

The PRE is defined as, in weight -%:
PRE = % Cr + 3.3 x % Mo +16 x % N
The PRE number for SAF 2205 and some compared materials are given in the following table.

Alloy	% Cr	% Mo	% N	PRE
SANMAC SAF 2205 Alloy 825 AISI 317L AISI 316L	22 21.5 18 17	3.2 3.0 3.5 2.2	0.18 - - -	>35 31 30 24

The ranking given by the PRE number has been confirmed in laboratory tests. This ranking can generally be used to predict the performance of an alloy in chloride containing environments. Laboratory determinations of critical temperature for initiation of pitting (CPT) at different chloride contents are shown in fig. 4. The chosen testing conditions have yielded results that agree well with practical experience. Thus, Sandvik SANMAC SAF 2205 can be used at considerably higher temperatures and chloride contents than AISI 304 and AISI 316 without pitting occurring. Sandvik SANMAC SAF 2205 is therefore far more serviceable in chloride-bearing environments than standard austenitic steels.

Stress corrosion cracking
The standard austenitic steels of the AISI 304L and AISI 316L types are prone to stress corrosion cracking (SCC) in chloride-bearing solutions at temperatures above 60°C (140°F). Duplex stainless steels are far less prone to this type of corrosion. Laboratory tests have shown the good resistance to stress corrosion cracking of SANMAC SAF 2205. Results from these tests are presented in fig. 5. The diagram indicates the temperature-chloride range within which Sandvik SANMAC SAF 2205 and the standard steels AISI 304L and AISI 316L can be used without a risk of stress corrosion cracking.

Figure 5. Resistance to stress corrosion cracking, laboratory results.

Intergranular corrosion
Sandvik SANMAC SAF 2205 easily pass intergranular corrosion testing according to ASTM A262 Practice E (Strauss' test).

Erosion corrosion
Steels of the AISI 316 type are attacked by erosion corrosion if exposed to flowing media containing highly abrasive solid particles, e.g. sand, or to media with very high flow velocities. Owing to its combination of high hardness and good corrosion resistance, Sandvik SANMAC SAF 2205 displays very good resistance under such conditions.

Corrosion fatigue
Sandvik SANMAC SAF 2205 possesses higher strength and better corrosion resistance than ordinary austenitic stainless steels. Sandvik SANMAC SAF 2205 therefore also possesses better fatigue strength under corrosive conditions than such steels.

Hot working

Sandvik SANMAC SAF 2205 is ductile at higher temperatures. The deformation resistance increases with decreasing temperature, and hot working should therefore be carried out at a material temperature of 975-1200°C (1787-2318 °F).
If the temperature falls below 950°C during hot working there is a risk for sigma phase formation, and the material must therefore be reheated.
Hot working of SANMAC SAF 2205 should be followed by solution annealing and quenching in accordance with the recommendations given for heat treatment.

Heat treatment

Sandvik SANMAC SAF 2205 stock programme bars are delivered in solution annealed and quenched condition. Billets are normally delivered in hot-worked and air-cooled condition, but can be solution annealed and quenched when demanded. If additional heat treatment is needed after further processing, the following is recommended:
Solution annealing at 1020 – 1100°C (1870 – 2010°F) followed by quenching.

Welding

The weldability of Sandvi SANMAC SAF 2205 is good. Suitable welding methods are manual metal-arc welding with covered electrodes or gas-shielded arc welding. Welding should be undertaken within the heat input range 0.5 – 2.5 kJ/mm. Max. interpass temperature is 250°C (482°F). Preheating or post-weld heat treatment is normally not necessary.
Matching filler metals are recommended in order to obtain a weld metal with optimum corrosion resistance and mechanical properties. For gas-shielded arc welding, we recommend Sandvik 22.8.3.L, and for manual metal-arc welding the covered electrode Sandvik 22.9.3.LR. Flux cored wire 22.9.3.LT is also available. These filler metals can also be used for welding SAF 2205 to carbon steels, stainless steels and nickel alloys. The covered electrode Sandvik 23.12.2.LR and the welding wire Sandvik 22.15.3.L, both of type AWS 309Mo with low carbon content, can also be used for this purpose.

Machining

Sandvik SANMAC SAF 2205 has very good machining properties. In this material machinability has been improved without jeopardising properties such as corrosion resistance and mechanical strength. The non-metallic inclusions in SANMAC steels are of great significance to improved machinability. In addition to sulphides, Sandvik SANMAC steels contain oxide inclusions, which improve chip breaking and reduce tool wear.
Fig. 6 shows the ranges within which you can choose cutting data to obtain a tool life of 7 minutes in the duplex material Sandvik SANMAC SAF 2205. The diagram is applicable for short cutting times. For long, continuous cuts, the cutting speeds should be reduced somewhat.

The lowest recommended cutting data is determined by the tendency of the material to stick to the insert (built-up edge), although the integrity of insert clamping and the stability of the machine are also of great significance.

The machining ranges are limited by different wear mechanisms. Once the type of wear has been determined, the cutting data can be optimized with the aid of the diagram.

Recommended insert and cutting data for turning of SANMAC SAF 2205 (starting values)

Insert		Cutting data				Application
Geometry	Grade	Feed		Cutting speed
		mm/rev.	in./rev.	m/min	ft/min
MF	GC2025	0.15	0.006	180	590	Finishing
MF	GC2025	0.22	0.009	150	490	Medium machining
MM	GC2035	0.25	0.010	110	360	Rough machining (roughing a low cutting speeds).

Turning in SANMAC SAF 2205 duplex steel is considerably demanding than in the SANMAC austenitic material. This is due mainly to the higher strength of SANMAC SAF 2205, as well as its greater tendency to adhere to the tool.

Figure 6. Cutting data recommendations for SANMAC SAF 2205. GC 2025 and GC 2035 refer ti Sandvik Coromant cemented-carbide insert grades.

The machining ranges are limited by different wear mechanisms. Once the type of wear has been determined, the cutting data can be optimized with the aid of the diagram.

Applications

Due to its excellent corrosion properties, Sandvik SANMAC SAF 2205 is a highly suitable material for service in environments containing chlorides and hydrogen sulphide. The material is suitable for use in production tubing and flowlines for the extraction of oil and gas from sour wells, in refineries and in process solutions contaminated with chlorides. Sandvik SANMAC SAF 2205 is particularly suitable for heat exchangers where chloride-bearing water or brackish water is used as a cooling medium. The steel is also suitable for use in dilute sulphuric acid solutions and for the handling of organic acids, e.g. acetic acid and mixtures.

The high strength of Sandvik SANMAC SAF 2205 makes the material an attractive alternative to the austenitic steels in structures subjected to heavy loads.

The good mechanical and corrosion properties make Sandvik SANMAC SAF 2205 an economical choice in many applications by reducing the life cycle cost of the equipment.

The good machining properties make Sandvik SANMAC SAF 2205 a superior alternative to standard 2205 grades and other duplex grades for applications subjected to all types of machining by extended tool life and possibilities to increase productivity.

Further information

Our data sheets and substantial technical information about our grades and products are available on the Sandvik Steel web-site www.steel.sandvik.com. The following printed matter can be ordered via the web-site or from our nearest Sandvik office.

General information
S-029-ENG	Stainless steels and cutting tools for better machining (Brochure)
S-02909-ENG	Stainless bar steel – Stock programme (Pocket card)
S-030-ENG	Semifinished products (Brochure) S-0301-ENG Billets for forgings (Brochure)
S-110-ENG	Pipe – tube – hollow bar, seamless standard programme in stainless (Brochure)
S-120-ENG	Duplex stainless steels – fighting corrosion worldwide (Brochure)
S-1874-ENG	Sandvik SAF 2205 – Duplex stainless steel (Data sheet)
S-33-38-ENG	LCC calculations and design examples for duplex stainless steels (Lecture)
S-51-51-ENG	Duplex stainless steels for demanding applications (Lecture)
S-51-52-ENG	LCC examples – Sandvik's stainless steel tubing (Lecture)
S-51-53-ENG	The Sandvik Duplex Family of stainless steels. Summary of data (Lecture)
S-51-54-ENG	Physical metallurgy and some characteristic properties of the Sandvik duplex stainless steels (Lecture)

Mechanical properties
S-32-27-ENG	Applicability of duplex stainless steels above 300°C (Lecture)
S-32-30-ENG	Mechanical properties of Sandvik duplex stainless steels (Lecture)

Machinability
S-0291-ENG	Cutting data for stainless steel (Brochure)
S-51-47-ENG	Machinability of duplex stainless steel (Lecture)
S-51-48-ENG	Machining charts for stainless steel (Lecture)

Corrosion
S-33-43-ENG	Chloride-induced stress corrosion cracking of duplex stainless steel. Models, test methods and experience (Lecture)
S-33-46-ENG	Corrosion resistance of duplex stainless steels in organic acids (Lecture)
S-33-47-ENG	Corrosion properties of duplex stainless steels. General corrosion, pitting and crevice corrosion (Lecture)
S-51-32-ENG	SCC resistance of stainless steels – laboratory data vs practical experience (Lecture)

Fabrication
S-51-33-ENG	Fabricating ferritic-austenitic stainless steels (Lecture)
S-51-39-ENG	Fabrication and practical experience of duplex stainless steels (Lecture)

Welding
S-1252-ENG	Your guide to easy welding of duplex stainless steel (Brochure)
S-91-45-ENG	Influence of different welding conditions on mechanical properties and corrosion resistance of Sandvik SAF 2205 (UNS S31803) (Lecture)
S-91-57-ENG	Welding practice for the Sandvik duplex stainless steels SAF 2304, SAF 2205 and SAF 2507 (Lecture)

Process industry
S-12136-ENG	Tough stuff for heat exchangers (Brochure)
S-51-55-ENG	Applications of duplex stainless steels in the chemical and petrochemical industry (Lecture)
S-52-83-ENG	Stainless steels for eliminating chloride-induced corrosion in ammonia/urea plants (Lecture)
S-52-85-ENG	Duplex stainless steels in the chemical industry (Lecture)

Oil & gas
S-13323-ENG	Engineering diagram Sanicro 28-110, Sanicro 28-130, SAF 2205-130 (Brochure)
S-13324-ENG	Effect of pH on the applicability of Sandvik SAF 2205 (Brochure)
S-13325-ENG	SCC resistance in H₂S / chloride environments of Sandvik SAF 2205 (Brochure)
S-133-ENG	Stainless steel products for oil and gas production (Brochure)
S-134-ENG	Speciality stainless steels in oil refineries (Brochure)
S-252-ENG	Wirelines (Brochure)
S-33-44-ENG	Testing and selection of duplex stainless steels for sour environments (Lecture)
S-33-45-ENG	Hydrogen embrittlement of duplex stainless steels in connexion with cathodic protection (Lecture)
S-58-10-ENG	The applicability of duplex stainless steels in sour environments (Lecture)
S-58-11-ENG	Coated duplex pipes for TOGI project" (Lecture) Reference lists
S-12911-ENG	Sandvik SAF 2205 – The traditional duplex stainless steel
S-13332-ENG	Sandvik SAF 2205 – References for the oil & gas industry, downhole applications
S-13334-ENG	Sandvik Sanicro 28 and SAF 22Cr. References for the oil & gas industry, downhole applications
S-12136-ENG	Tough stuff for heat exchangers (Brochure)
S-51-55-ENG	Applications of duplex stainless steels in the chemical and petrochemical industry (Lecture)
S-52-83-ENG	Stainless steels for eliminating chloride-induced corrosion in ammonia/urea plants (Lecture)
S-52-85-ENG	Duplex stainless steels in the chemical industry (Lecture) oil & gas industry, downhole applications

Pulp & paper
S-54-23-ENG	High-strength stainless steels and composite tubes for the pulp and paper industry (Lecture)

Reference lists
S-12911-ENG	Sandvik SAF 2205 – The traditional duplex stainless steel
S-13332-ENG	Sandvik SAF 2205 – References for the oil & gas industry, downhole applications
S-13334-ENG	Sandvik Sanicro 28 and SAF 22Cr. References for the oil & gas industry, downhole applications

Претензии
Данные рекомендации предоставлены только для информации, целесообразность применения определенного материала мы можем сообщить только после того как узнаем реальные условия эксплуатации. Постоянное развитие наших материалов приводит к изменениям в технической документации. Данный каталог действителен только для материалов Sandvik. Другие материалы при одинаковых международных спецификациях могут не обладать механическими и коррозионными свойствами, представленными в данном каталоге.

Legal Notice | Privacy Policy |Contact Us | Latest update:07/22/2003