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Nitric acid is strongly oxidising and promotes the resistance of stainless steel to corrosion. Generally stainless steel are resistant to corrosion in nitric acid. Nitric acid is used in the chemical passivation of stainless steel. Commercially concentrated acid is around 65 wt % (sg = 1.40). Higher concentrations obtained by removing water, which can involve the use of sulphuric acid, which has a high affinity for water. Corrosion resistance of stainless steel Nitric acid is strongly oxidising and attacks most metals but due to its powerful oxidising nature, it promotes the resistance of stainless steel to corrosion. Generally stainless steel are resistant to corrosion in nitric acid over a wide range of concentration and temperature. The ‘helpful’ oxidising properties of nitric acid are used in the chemical passivation of stainless steel. The iso-corrosion diagram 0.1mm/year lines for the 304 and 316 types coincide (purple). (The broken line represents the boiling point) This shows that the 304 types can be used over a wide range of concentration and temperature, up to 95%, for storage applications. The 304 types are preferable to 316 types for nitric acid applications however. This is an exception to the ‘general rule’ for stainless steels where the 316 types are normally found to be more corrosion resistant than 304 types. Over 95% concentration, aluminium alloys should be considered OR 4% silicon stainless steels. Any additional chlorides or fluorides in nitric acid may increase corrosion rates by pitting. Risk of localised corrosion in concentrated acids Localised attack at grain boundaries (IC) can occur in hot concentrated nitric acid. This can occur in the heat-affected-zone (HAZ) of welds. Prolonged heating in a range of around 600-800 degC, followed by exposure to concentrated nitric acid, can also result in localised attack, due to the precipitation of the brittle “intermetallic” (iron-chromium) compounds (sigma phase). Avoiding localised attack in concentrated acid To avoid the risk of localised corrosion, especially where post weld heat treatment is impractical, the low carbon, 304L types should be considered. Solution heat treatment (1050 -1100 degC followed by fast cooling) on the standard carbon 304 types can be considered as an alternative. These treatments should also re-dissolve any sigma formed. Compostions of 304L types have been used with silicon, phosphorous & sulphur limited to very low residual levels to improve the resistance in hot concentrated nitric acid. Uses for nitric acid with stainless steels Nitric acid is widely used in the chemical ‘passivation’ of stainless steels. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Sodium Hydroxide (Caustic Soda) is a strong base. It is used in metal degreasing and cleaning processes in a wide range of industry applications. Stainless steel types 304 and 316 can be considered resistant below 80 degC, up to the limit of solubility. Both 304 and 316 stainless steel types are resistant to a wide range of concentration and temperature. Below 80 degC they can be considered resistant to any concentration of sodium hydroxide, up to the limit of solubility. There can be a risk ofstress corrosion cracking (SCC) attack at higher temperatures, which is common to both the 304 and 316 types. Corrosion resistance of stainless steel The iso-corrosion diagram 0.1mm/year lines for 304 and 316 types coincide (purple). (The broken line represents the boiling point) This should not be an issue if service temperatures are limited to a 95 degC maximum. Risk of stress corrosion cracking attack ‘Caustic stress corrosion cracking’ occurs at higher temperatures than chloride stress corrosion cracking (which can occur at temperatures as low as 60 degC). The area of risk in sodium hydroxide is shown on the iso-corrosion diagram by the area bounded by a green line. Risk of pitting attack by chlorides Chlorides should not pose as great a pitting and crevice corrosion attack threat in sodium hydroxide as they do in acid solutions. The high pH values of the ‘basic’ sodium hydroxide helps arrest the normal mechanisms of attack. Care may be necessary when selecting 304 types for sodium hydroxide cleaning systems or tanks, where ‘carry-over’ of chlorides could occur from prior treatment stages. It may be better to consider 316 or the 316L types if this could occur. The 316L type may be a marginally better choice where the steel may have been sensitised in the heat-affected zone (HAZ) of welds and post weld softening / stress relief is not practical. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Acetic acid is a weak reducing acid. It is used in plastics manufacture and is a constituent of foods as vinegar. Ferritic stainless steels such as 430 type can be considered but normally the 304 types are used for most applications, including handling and storage.  Acetic anhydride (CH3CO)2O can be aggressive to either 304 or 316 types in the absence of any water and in the presence of chlorides. Peracetic acid CH3C(O)OOH (peroxyacetic acid) should be safe with stainless steel.Vinyl acetate C4H6O2 may be considered with the 316 grades for ambient temperature storage applications. Commercially concentrated acid is around 99wt. % (glacial acetic acid). Corrosion resistance of stainless steel Ferritic stainless steel such as the 430 / 1.4016 type can be considered for most acid concentrations at ambient temperatures, but normally austenitic are preferred as pitting corrosion has been reported in industrial plant and equipment. The 304 types are normally considered as suitable grades for most applications, including handling and storage. The iso-corrosion diagram 0.1mm/year lines for the 316 / 1.4401 (red) types show that they can be expected to provide better resistance over about 5% concentrations, at temperature over 90 degC, than the 304 (blue) types. (The boiling point corresponds to the red line for 316 types) At concentrations above about 80%, the 316 types are usually considered a better choice than the 304 types, especially where temperatures exceed 70 degC, where there is a risk of localised attack to the 304 types. For processing equipment, 316L is considered a better choice than the 30 4/304L or 316 types. Intergranular attack can be an issue in weld heat affected zones, if acid contact temperatures exceed around 60 degC. As with other similar acid contact applications, the low carbon, 304L should be considered rather than the standard 304 types. In common with most acid handling applications, chloride contamination can cause pitting corrosion and so in these cases more pitting resistant grades may need to be considered. Contamination of acetic acid with the more aggressive formic acid (HCOOH) can result in an unexpected reduction in corrosion resista nce of the 316 types. The 304 types may be particularly vulnerable under these conditions. Acetic anhydride (CH3CO)2O Acetic anhydride (CH3CO)2O can be aggressive to either 304 or 316 types in the absence of any water and in the presence of chlorides. The risk of pitting corrosion can be reduced if grades such as the austenitic 1.4539 or the 6% molybdenum grades are considered in these extreme conditions. Peracetic acid CH3C(O)OOH Peracetic acid CH3C(O)OOH which is also known as peroxyacetic acid, is used as a disinfectant (sanitiser) in food, medical and water treatment related industries. It should be safe for uses that involve contact with stainless steel items. Vinyl acetate C4H6O2 Vinyl acetate C4H6O2 is an intermediate product used in the manufacture of chemicals such as adhesives and paints. The only information available suggests that the 316 types should be suitable for ambient temperature storage applications. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Sodium hypochlorite only exists in solutions. The solution can be unstable, giving off chlorine gas. Sodium hypochlorite is not stable as a solid chemical. The hypochlorites, although alkaline, are oxidising. Commercially concentrated Sodium hypochlorite is around 15-wt %. Household bleach solutions are around 5.25% sodium hypochlorite. The hypochlorite ion (OCl-) is aggressive to stainless steel, acting in a similar way to wet chlorine gas, and like the chloride ion (Cl-), is a dangerous pitting corrosion hazard. Corrosion resistance of stainless steel Pitting or crevice corrosion can occur on most stainless steel grades in a 5% solution at ambient temperature. There is an additional risk of stress corrosion cracking (SCC) at higher temperatures. Stainless steel should not be considered suitable for storage or transport tank applications with concentrated (15%) hypochlorite solutions or bleaches (5%). Contact with household bleach Pitting corrosion has been reported from household bleach spills on stainless steel (304 type) sinks in domestic environments. If this occurs immediate dilution by rinsing should avoid pitting, but if left overnight, pitting can result. Disinfecting or sanitising 304 stainless steel or 316 stainless steel items with dilute hypochlorite solutions can be done with care, but it is important that the temperature and contact time is kept to a minimum and that the solution is thoroughly rinsed away afterwards. Safe residual water chlorine levels for sterilization As a guide, 15-20 ppm (mg/lt) residual chlorine solutions at ambient temperatures should be safe with 316 stainless steel types for a 24-hour maximum contact time, if followed by rinsing. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Duplex 2304 is a 23‰ Cr, 4‰ Nickel, Mo free duplex stainless steel (23.04). We hold stock of duplex alloys in plate, flanges, pipes, and bars from our warehouse in the CN. We often meet specialist alloy profiling requirements and are a global supplier. The alloy lean duplex 2304 has similar corrosion resistance properties to 316L. Furthermore, its mechanical properties i.e. yield strength, are twice those of 304/316 austenitic grades. This allows the designer to save weight, particularly for properly designed pressure vessel applications. The alloy is particularly suitable for applications covering the -50°C/+300°C (-58°F/572°F) temperature range. Lower temperatures may also be considered, but need some restrictions, particularly for welded structures. With its duplex microstructure, low nickel and high chromium contents, the alloy has improved stress corrosion resistance properties compared to 304 and 316 austenitic grades. Tensile Strength Properties (Minimum Values)°CRp 0.2 MPaRp 1.0 MPaRm MPa20400440600100330365570200280310530300230260490 °FYS 0.2% KSIYS 1.0% KSI  UTS KSIElongation %6858648725212485383253924145772057233387120 Values obtained for hot rolled plates (th ≤ 2”). Duplex 2304 (S32304 1.4362) must not be used for a long time at temperatures higher than 300°C (572°F), where precipitation hardening phenomenon occurs. Toughness Values (KCV Minimum Values)Temp. -50°C+20°C -60°F+70°FSingle 75 J/cm90 J/cm 54 ft.lbs65 ft. lbsAverage (5) 90 J/cm150 J/cm 65 ft.lbs87 ft.lbs Hardness (Typical Values)Average (5)HV10 180-230HB : 180-230HRC _ 20 Applications: Duplex 2304 is generally used in the same applications in which Alloys 304 and 316L are used. Some examples of these applications include: Chloride containing environments Welded pipe systems within the Pulp and Paper, Chemical and Petrochemical, and Water Treatment industries Transportations Heat exchanger tubes Duplex 2304 Pipe Architecture, building, construction Pressure vessels Caustic solutions, organic acids Food industry Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

If the material type or stainless steel grade carbon content percentage you know? hardness test is a simple way to verify that a material has been properly heat treated. Hardness testers such as Rockwell, Brinell, and Vickers can be useful to check metals for actual hardness. Hardness tests are generally considered nondestructive, hardness testing does leave a small pit in the surface; therefore, hardness tests should not be used on sealing surfaces, fatigue critical parts, load bearing areas,etc., components which will be used in critical applications . These hardness tests provide a convenient means for determining, within reasonable limits, the tensile strength of steel. It has several limitations in that it is not suitable for very soft or very hard stainless steel pipe. Hardness testing of aluminum alloys should be limited to distinguishing between annealed and heat-treated material of the same aluminum alloy. In hardness testing, the thickness and the edge distance of the specimen being tested are two factors that must be considered to avoid distortion of the metal. Several readings should be taken and the results averaged. In general, the higher the tensile strength, the greater its hardness. The Shore (Scleroscope) Hardness Test The Scleroscope test consists of dropping a diamond tipped hammer, which falls inside a glass tube under the force of its ownweight from a fixed height, onto the test specimen. The height of the rebound travel of the hammer is measured on a graduated scale.The harder the material, the higher the rebound. The scale of the rebound is arbitrarily chosen and consists on Shore units, pided into 100 parts, which represent the average rebound from pure hardened high-carbon steel. The scale is continued higher than 100 to to allow for metals having greater hardness.  The shore scleroscope test does not normally mark the material under test. The Shore Scleroscope measures hardness in relation to the elasticity of the material.    Advantages of this method are portability and non-marking of the test surface.  Knoop The Knoop indenter has a polished rhombohedral shape with an included longitudinal angle of 172° 30’ and an included transverse angle of 130° 0’. The narrowness of the indenter makes it ideal for testing specimens with steep hardness gradients and coatings. Knoop is a better choice for hardness testing of hard brittle materials.  Jominy Hardenability The Jominy test involves heating a test specimen of stainless steel 25mm diameter and 100mm long to an austenitising temperature and quenching from one end with a controlled and standardized jet of water. After quenching, the hardness is measured at intervals taken form the quenched end. The hardness gradient along the test surface provides an indication of the material’s hardenability. Moh’s Hardness Scale The Moh’s hardness scale consists of 10 minerals arranged in order from 1 to 10.    Diamond is rated as the hardest and is indexed as 10; talc as the softest with index number 1. Each mineral in the scale will scratch all those below it as follows: Diamond 10 Corundum 9 Topaz 8 Quartz 7 Orthoclase (Feldspar) 6 Aptite 5 Fluorite 4 Calcite 3 Gypsum 2 Talc 1 Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

NACE MR 0175/ISO 15156 is a Materials Standard issued by the National Association of Corrosion Engineers. It is originally a US standard intended to assess the suitability of materials for oilfield equipment where sulphide (sulfide) stress corrosion cracking may be a risk in hydrogen sulphide (sour) environments. However, the world standards body ISO has issued it under its own “brand”. The latest edition includes technical corrigenda from 2005. The standard specifies the types of corrosion resistant materials including stainless steel that can be used in specific oilfield environments and places limits on the hardness of the material. This applies both to parent and weld material. The maximum hardness is usually defined in terms of the Rockwell ‘C’ scale. No conversion to other hardness scale is given in MR 0175 which presents one problem as softened stainless steel hardness are measured using either the Rockwell ‘B’, Vickers or Brinell scales. Approximate conversions are available. Summary of MR 0175 Requirements A wide range of materials is covered by the standard including most types (families) of stainless steel. The table below shows some of these grades. However, this summary is intended to only give a general idea of this complex standard and is not a substitute for the original document.Stainless Steel TypeGrades Included                                 Comments                                                                                         Ferritic Stainless Steel405,430, 409, 434, 436, 442, 444, 445, 446, 447, 448Hardness up  to 22 HRCMartensitic Stainless Steel410, 420Hardness up to 22 HRCMartensitic Stainless SteelF6NMHardness up to 23 HRCMartensitic Stainless SteelS41425Hardness up to 28 HRCAustenitic Stainless Steel201, 202, 302, 304, 304L, 305, 309, 310, 316, 316L, 317, 321, 347, S31254(254SMO), N08904(904L), N08926(1925hMo)Solution annealed, no cold work to enhance properties, hardness up to 22 HRCAustenitic Stainless SteelS20910Hardness up to 35 HRCDuplex Stainless Steel S31803 (1.4462), S32520 (UR 52N+),S32750 (2507), S32760 (Zeron 100), S32550(Ferralium 255)PREN >30 solution annealed condition, ferrite content 35% to 65%, or 30 to 70% in welds. Note that the general restriction of 28 HRC in previous editions is not found in this latest edition of the standard. There is a specific restriction on HIP’d S31803 to 25HRC. For some applications cold worked material is allowed up to 36HRC Precipitation Hardening17-4 PH33 HRC Age hardening at 620 deg CPrecipitation Hardening  S4500031 HRC Age hardening at 620 deg CPrecipitation HardeningS6628635 HRC Free machining grades such as the 303 and 416 types are excluded from of NACE MR 0175/ISO 15156 Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

These stainless steel have the good heat-resisting performance, is suitable in the steam environment or 55 0℃ and the above temperature. 310S Stainless Steel | 309S Stainless Steel | 304H Stainless Steel | 321H Stainless Steel | 347H Stainless Steel Standard: ASTM A213,EN 10216-5  Anticorrosion environment: The temperature may reach 800 ℃  Application: Boiler 1.4828-X15CrNiSi20-12  Standard :SEW 470,DIN EN 10095  Equal to :Avesta 4828,Uginox R20-12,Cronifer 2012  Anticorrosion environment: The temperature may reach 1000 ℃ , the oxygen content low azotic gas.  Apply to: Makes the furnace, the petrochemical industry 1.4841-X15CrNiSi25-21  Standard :SEW 470,DIN EN 10095  Equal to :Cronifer 2520  Anticorrosion environment: The temperature may reach 1100 ℃ , the oxidation and the reducing gas (low sulphur content)  Apply to: Makes the furnace, the petrochemical industry 1.4876-X10NiCrAITi32-21  Standard:SEW 470,VdTUV-Wbl.412,DIN EN 10095  Equal to:Nicrofer 3220/3220H,Incoloy 800  Anticorrosion environment: The temperature may reach 1100 ℃ , the long time barometric pressure or the vapor tension  Apply to: The heat change installment, the steam response ins tallment, make the furnace, the petrochemical industry Table 1 Short Term Tensile Strength vs Temperature (in the annealed condition except for 410)Temperature304 Stainless Steel & TS ksi316 Stainless Steel YS ksi309 Stainless Steel & TS ksi309S Stainless Steel YS ksi310 Stainless Steel & TS ksi 310S Stainless Steel YS ksi410* Stainless Steel TS ksi YS ksi430 Stainless Steel TS ksi YS ksiRoom Temp.844290459045110857550400°F823680388434108856538600°F773275368231102826236800°F742871347828928055351000°F702664307026747038281200°F582353275925444022161400°F342035204124——1081600°F241825202622——54 * heat treated by oil quenching from 1800° F and tempering at 1200° F Table 2 Generally Accepted Service TemperaturesMaterialIntermittent  Service TemperatureContinuous  Service TemperatureAustenitic Stainless Steel 304 Stainless Steel 1600°F (870°C)1700°F (925°C)316 Stainless Steel1600°F (870°C)1700°F (925°C)309 Stainless Steel1800°F (980°C)2000°F (1095°C)310 Stainless Steel1900°F (1035°C)2100°F (1150°C)Martensitic Stainless Steel 410 Stainless Steel1500°F (815°C)1300°F (705°C)420 Stainless Steel1350°F (735°C)1150°F (620°C)Ferritic Stainless Steel 430 Stainless Steel1600°F (870°C)1500°F (815°C) Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Stainless steel have good strength and good resistance to corrosion and oxidation at elevated temperatures. Stainless steel are used at temperatures up to 1700° F for stainless steel 304 and stainless steel 316 and up to 2000 F for the high temperature stainless steel grade 309(S) and up to 2100° F for 310(S). Stainless steel is used extensively in heat exchanger, super-heaters, boiler, feed water heaters, valves and main steam lines as well as aircraft and aerospace applications. Figure 1 gives a broad concept of the hot strength advantages of stainless steel in comparison to low carbon unalloyed steel. Table 1 shows the short term tensile strength and yield strength vs temperature. Table 2 shows the generally accepted temperatures for both intermittent and continuous service. With time and temperature, changes in metallurgical structure can be expected with any metal. In stainless steel, the changes can be softening, carbide precipitation, or embrittlement. Softening or loss of strength occurs in the 300 series (304, 316, etc.) stainless steel at about 1000° F and at about 900° F for the hardenable 400 (410<, 420, 440) series and 800° F for the non-hardenable 400 (409, 430) series (refer to Table 1). Carbide precipitation can occur in the 300 series in the temperature range 800 – 1600° F. It can be deterred by choosing a grade designed to prevent carbide precipitation i.e., 347 (Cb added) or 321 (Titanium added). If carbide precipitation does occur, it can be removed by heating above 1900° and cooling quickly. Hardenable 400 series with greater than 12% chromium as well as the non-hardenable 400 series and the duplex stainless steel are subject to embrittlement when exposed to temperature of 700 – 950° F over an extended period of time. This is sometimes call 885F embrittlement because this is the temperature at which the embrittlement is the most rapid. 885F embrittlement results in low ductility and increased hardness and tensile strength at room temperature, but retains its desirable mechanical properties at operating temperatures. Table 1 Short Term Tensile Strength vs Temperature (in the annealed condition except for 410)Temperature304 Stainless Steel & TSksi316 Stainless Steel YSksi309 Stainless Steel & TSksi309S Stainless Steel YSksi310 Stainless Steel & TSksi 310S Stainless Steel YSksi410* Stainless Steel TSksi YS ksi430 Stainless Steel TSksi YS ksiRoom Temp.844290459045110857550400°F823680388434108856538600°F773275368231102826236800°F742871347828928055351000°F702664307026747038281200°F582353275925444022161400°F342035204124——1081600°F241825202622——54 * heat treated by oil quenching from 1800° F and tempering at 1200° F Table 2 Generally Accepted Service TemperaturesMaterialIntermittent  Service TemperatureContinuous  Service TemperatureAustenitic 3041600°F (870°C)1700°F (925°C)3161600°F (870°C)1700°F (925°C)3091800°F (980°C)2000°F (1095°C)3101900°F (1035°C)2100°F (1150°C)Martensitic 4101500°F (815°C)1300°F (705°C)4201350°F (735°C)1150°F (620°C)Ferritic 4301600°F (870°C)1500°F (815°C) It may seem to be illogical that the “continuous” service temperature would be higher than the “intermittent” service temperature for the 300 series grades. The answer is that intermittent service involves “thermal cycling”, which can cause the high temperature scale formed to crack and spall. This occurs because of the difference in the coefficient of expansion between the stainless steel and the scale. As a result of this scaling and cracking, there is a greater deterioration of thesurface than will occur if the temperature is continuous. Therefore the suggested intermittent service temperatures are lower. This is not the case for the 400 series (both ferritic and martensitic grades). The reason for this is not known. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

In this test a standard constant load, usually 500 to 3,000 kg, is applied to a smooth flat metal surface by a hardened steel ball type indenter, 10 mm in diameter. The 500-kg load is usually used for testing nonferrous metals such as copper and aluminum alloys, whereas the 3,000-kg load is most often used for testing harder metals such as stainless steel tube and cast irons. The numerical value of Brinell Hardness (HB), is equal to the load, pided by the surface area of the resulting spherical impression. ​ The Brinell hardness test consists of indenting the test material with a 10 mm diameter hardened steel or carbide ball subjected to a load of 3000 kgf (29 430 N). For softer materials the load can be reduced to 1500 kgf (14 715 N) or 500 kgf (4 905 N ) to avoid excessive indentation. The full load is normally applied for 10 to 15 seconds for harder ferrous metals and 30 seconds for other metal softer metal. The diameter of the indentation left in the test material is measured with a microscope. The Brinell hardness number is calculated by piding the load applied by the surface area of the indentation. Where P is the load, in kg; D is the diameter of the ball, in mm; and d is the diameter of the indentation, in mm. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

High temperature Stainless Steel Pipes maintain their mechanical properties when exposed to elevated temperatures on either a short- or long-term basis. All materials selection must be determined by the application and operating conditions in each inpidual case. With their increased concentration of chrome, silicon and aluminium they are especially resistant under the influence of hot gases as well as in salt and metal melting. However, the inpidual corrosion resistance is always dependent on the surrounding conditions, and can therefore not be precisely determined in a single testing. Besides the common Austenitic High Temperature Alloys above (i.e., 1.4948, 1.4878,1.4828, 1.4833, and 1.4845), there are three proprietary Stainless steel alloys: 153 MA, 253 MA, and 353 MA. These three Stainless steel alloys are based on the same concept. Improved oxidation resistance by an increased silicon content and addition of very small quantities of rare earth metals (micro-alloying => MA). Enhanced creep strength due to increased contents of nitrogen (and carbon for 253 MA). In many cases, theproperties of these steels have proved to be equivalent or even superior to those of grades with higher contents of alloying elements. 153 MA is normally intended for use at somewhat lower service temperature than the other two grades.  Depending on the area of application these temperatures can rise e.g. to – 500°C (932°F) in chemical processes – 700°C (1,292°F) in power plant applications – 1,000°C (1,832°F) for furnace engineering Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)

Super Duplex 2507 (F53 / 1.4410 / UNS S32750) has excellent corrosion resistance to a wide variety of media, with outstanding resistance to pitting and crevice corrosion in seawater and other chloride containing environments, with Critical Pitting Temperature exceeding 50°C.UNS S32750 (F53 / 1.4410 / Alloy 2507) exhibits a low coefficient of thermal expansion and higher heat conductivity than austenitic steels and is suitable for working temperatures up to 300°C. Trade NameCommon NameUNSASTM A276/ A479ASTM A182ASTM 240ASTM A789/A790 (ASME)European(ASME)(ASME) Grade GradeBarForgingPlatePipe WerkstoffAlloy 25072507S32750S32750F53S32750S327501.4410 GradeChemistry (Typical Values)MechanicalsSpecificationCrNiMoCuNWSiMnP maxS maxC maxFeUTS N/mm² (min)0.20% Proof (min)Elong % (min)Hardness HB (max)PREN250725.07.03.80.750.250.280.801.200.0350.0200.030Bal750500-5502527041 Specifications of UNS S32750 0.2% Proof Stress (N/mm2 ) [ksi] minimum550[79.8]Ultimate Tensile Strength (N/mm2) [ksi] minimum800 [116]Elongation (%) minimum25Hardness (HBN)270 maxReduction of Cross Section Area (%)45Charpy 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 TestingASTM G48A Corrosion test at 40°CNo pitting and weight loss <4.0g/m2Ultrasonic TestingAccording to ASTM A388Ferrite Content35%-55%MicrostructureMicrostructure certified free from grain boundary carbides, sigma, chi and laves phases Physical Properties of UNS S32750 Density (Kg.m-1)7810Magnetic Permeability33Young’s Modulus (N/mm2)199 x 103Specific Heat, 20°C (J.Kg-1.°K-1)475Fracture Toughness, Kq (MPa.m)475Specific Electrical Resistance, 20°C (µO.m)0.80Thermal conductivity, 20°C (W.m-1.°K-1)14.2Mean coefficient of thermal expansion, 20-100°C (°K-1)11.1 x 10-6 Applications of UNS S32750 Chemical Process Industry:Due to its high corrosion resistance UNS S32750 is ideal for use in Nitric Acid Processes, Polypropylene Production, PVC Production, Dioxide, 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:Super Duplex UNS S32750 Flanges, Super Duplex UNS S32750 Valves, Super Duplex UNS S32750 Pipes, Super Duplex UNS S32750 Pipe Fittings Pollution Control:Fans and pumps, Wet Scrubbers, Incinerators 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:Fertiliser Production (Wet phosphoric acid) Civil Engineering:Sewage Treatment UNS S32750 Features Super Duplex UNS S32750 has excellent corrosion resistance in a wide variety of corrosive media making it ideal for use in environments exposed to the harshest chemical conditions. It has outstanding resistance to pitting and crevice corrosion in seawater and other chloride containing environments, with Critical Pitting Temperature exceeding 50°C. Compared to austenitic and 22%Cr duplex stainless steels, UNS S32750 is of higher strength and even more suitable in situations where it will be exposed to extremely high stresses. This combined with its excellent ductility and impact strength at both ambient and sub-zero temperatures further increases its appeal as the ultimate super duplex grade. High resistance to abrasion, erosion and cavitation erosion combined with excellent resistance to stress corrosion cracking in chloride containing environments makesUNS S32750 perfect for use in the Oil and Gas Industries where subsea equipment is subject to some of the harshest chloride containing conditions in the world. UNS S32750 is used for oilfield equipment where sulphide stress corrosion cracking may be a risk in hydrogen sulphide (sour) environments. UNS S32750 is also ASME Approved for Pressure Vessel applications KEY Features of UNS S32750 UNS S32750 has excellent corrosion resistance in a wide variety of corrosive chemicals Outstanding resistance to pitting and crevice corrosion in seawater and other chloride containing environments, with Critical Pitting Temperature exceeding 50°C High strength compared to austenitic and 22%Cr duplex stainless steels Excellent ductility and impact strength at both ambient and sub-zero temperatures High resistance to abrasion, erosion and cavitation erosion Excellent resistance to stress corrosion cracking in chloride containing environments ASME Approval for Pressure Vessel application Corrosion TestingG48A Corrosion Test at 50°C (122°F)Seawater corrosion test, demonstrates the absence of Sigma and otherdeleterious phases such as nitrides.Confirms practical pitting resistance rather than the theoretical PREN.Common Test ResultsNo Pitting and weight loss <4g/m²(For 255 SD50 weight loss is <0.8g/m²) Impact Testing Charpy  ‘V’ notch  Typically carried out at both roomtemperature and -46°C (-51°F) to ensure suitability for  offshore  applications and the absence of Sigma phase which can reduce toughness.Common Test Results Room Temp :250-350 J (185-260 ft.lb) -46°C (-51°F) :40-120 J (29-89 ft.lb) Key Reasons to Choose Super Duplex·    High Strength ·    Excellent Corrosion Resistance ·    Suitable for sub-zero Service ·    Extended Lifecycle ·    10% Lighter then 316 ·    Cost Saving over Nickel Alloys Super Duplex 2507 (F53 / 1.4410 / UNS S32750) has excellent corrosion resistance to a wide variety of media, with outstanding resistance to pitting and crevice corrosion in seawater and other chloride containing environments, with Critical Pitting Temperature exceeding 50°C. UNS S32750 (F53 / 1.4410 / Alloy 32750) exhibits a low coefficient of thermal expansion and higher heat conductivity than austenitic steels and is suitable for working temperatures up to 300°C. UNS S32750 (F53 / 1.4401) having gained ASME Approval for Pressure Vessel applications Alloy 32750 can be used in a wide variety of applications. Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)