45N austénitics. PREN = Cr + 3.3Mo + 16N S I

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1 Min YS (Mpa).3 1., 3,5 5, ,15 General presentation Mechanical properties in bars (YS & UTS) are better than those of 316L and also those of 316LN Better Corrosion Resistance than that of 316L 5N duplex 35N N L LN austénitics PREN = Cr + 3.3Mo + 16N Classification Duplex stainless steel Designation Material N Europe USA EN ASTM ISO XCrNiN3-4 S I is supplied according to EN 88-3 and to ASTM A76 Other material name Common name France Germany Sweden AFNOR DIN S.S 34 Z3CN3-4 Az Micro Structure The chemical composition is balanced to obtain 4-6% ferrite after annealing between 95 and 15 C followed by a fast cooling. The sensitivity to precipitation of (, ) intermetallic phases (which cause embrittlement) is much lower than that of Duplex 446. Typically,, phase precipitation requires over 1 hours at 8 C, a situation seldom encountered in processing operations. Precipitation of ' phase can occur under long term holding in the 35 C - 55 C temperature range, leading to embrittlement. Thus, the maximum service temperature should not exceed 3 C. Microstructure of (grey: ferrite ; white: austenite) works. Ugitech assumes no liability for the use or application of any posted data printed herein. Please contact UGITECH Technical help desk for assistance.

2 Température ( C) Pitting Potential(mV/ECS).3 1., 3,5 5, ,15 Mechanical properties exhibits attractive mechanical properties: YS and UTS values are thus twice as high for bars as those of a type or 316L grade. Rm (Mpa) Rp, (Mpa) A% Z% Turned Bars 63 / / 53 4 / 5 7/8 Drawn Bars (according to the amount of cold work ) 8 / / 75 / 3 65 / 75 Wire Rod 66 / 78 (84 max) 38 / 5 4 / 5 Drawn Wire* ex : Ø mm écroui Ø mm recuit * Values given for indication only. Refer to work hardening curves in the wire drawing chapter. at -46 C at C V Notch Toughness 7,5 daj/cm² 9, daj/cm² Physical properties Corrosion resistance Elasticity Thermal Expansion Electrical Tempera-ture Density Modulus conductivity coefficient resistivity ( C) (kg/dm 3 ) (N/mm ) (W/m. C) ( / C) (µω.mm) 7,8 16,7-8 Between and , x Generalized corrosion The grade can replace 316L (444) in most known applications; in particular: construction market for exposure in urban or maritime atmosphere pulp and paper industry chemical industry, for sulfuric acid production for instance etc. This is illustrated by the corrosion diagrams in HSO4 an in NaCl media Note: for use in boiling organic acids, please inquire 15 45N N L Uniform Corrosion Resistance in H SO 4 M medium Peak Activity Current (µa/cm²) Résistance à la corrosion sous contrainte higher 35N lower 316L higher Pitting Corrosion Resistance in fissures Chloride (NaCl) Medium Localized corrosion Pitting Corrosion The grade exhibits a bettre pitting corrosion resistance in NaCl medium than 316L (444) 7343 UGINE Cedex - France pas de fissures NaCl.86M, 55 C, ph=6.6 NaCl.5M, 7 C, ph=6.6 fissures pas de fissures 316L N N lower 1 1 Cl - (ppm) Stress Corrosion Cracking (SCC)

3 Rm (MPa) Allongement à rupture (%).3 1., 3,5 5, ,15 Stress corrosion cracking (SCC) Stress Corrosion Cracking tests in a Chloride Medium ( 8 ppm O ) at ph=7, under a stress level exceeding the elastic limit and for more than hours have shown that performs better than 316L (444). may be used in this type of solution up to 13 C without risk of SCC. By contrast, for 316L (444), the temperature should not exceed 5 C. Hot transformation Cold transformation Hot forging grade can be readily forged between 15 and 95 C, even though it is not as easy as for the usual austenitic grades (34 & 316). The hot workability depends on the ferrite content, which in turn increases with temperature: high temperatures will bring the best forging ability. High temperature flow stresses of duplex grades are lower than that of austenitic grades. Thus, less mechanical power is required to forge a duplex grade. Precautions should be taken to avoid creep deformation. After hot forming, a fast cooling (water or air) is necessary to prevent precipitation of sigma phase. Solution annealing is then optional. If forging finishes around 9 C, mechanical properties (YS and UTS) will increase due to strain-hardening. Wire drawing Profiling The is suitable for wire drawing and can be work hardened more than a 316L (1.444), in comparable fashion to a 3 (1.431). The work hardened can also be used for spring wire. Courbes d'écrouissage comparées : Rm et A% / 35N / 316L / 316LN Déformation rationnelle =ln(s/s) Rp. (MPa) Courbes d'écrouissage comparées : limite d'élasticité / 35N / 316L / 316LN Déformation rationnelle =ln(s/s) Cold heading can be used for cold heading to replace 444 and 4578, if a certain number of precautions are taken. It allows the manufacture of both ordinary and technical parts if the heading is not too severe. When a cruciform recess-type reference part was manufactured at the R&D Center, measurement of the heading force showed an additional force of % for the duplex in comparison with the and the UGINE Cedex - France 3

4 Max cheap flow*** (cm 3 /min) Vb 15/.15 (m/min) Cross recess depth measured (H measured / H initial) Relative force at the second blow.3 1., 3,5 5, ,15 1,% Forces curve at parts on the second blow 8,% 7 8,% 6,% 4,% P 436-P1 444-P1,%,% 8 1 Number of parts Stamp wear will also be more significant if 436 is used, in comparison with and When manufacturing a cross-head screw, without lubrication (acceleration of the test), the stamp broke after parts with the 436, compared with 9 parts for the and over 1, with the After cold heading, with UGI 436 the free edge surface is smooth, contrary to and 1.444, as shown by simple crushing between two piles. The corrosion resistance of the cold headed parts is identical to that of parts manufactured with and , to the extent that no severe heading defect was generated. If the manufacture of the parts is performed with care and the parts are correctly cleaned with rotation (trommel, etc.), then corrosion resistance can be significantly higher than that of the Machinability Turning: In turning operations (Vb 15/.15 test with the Kennametal KC95 tool), the UGI 436 grade appears better than EN 446 and equivalent to UGIMA 444. Tool/material tests are to be performed to complement these results Turning: Vb 15/.15 test 45N N L - IMA L - IMA444HM Drilling Drilling ( 4 mm high-speed steel drill): for 4 mm drilling, chip containment creates the same problem with respect to chip removal as that observed with Duplex 446, due to poor chip breakability. * Max. chip flow for 114 holes 16 mm deep using the same drill.,5 1,5 1,5 "High-speed steel" screw machining/drilling (4 mm diameter) 45N N L - IMA L - IMA444HM 7343 UGINE Cedex - France 4

5 Max cheap flow*** (cm 3 /min) Max cheap flow** (cm 3 /min).3 1., 3,5 5, ,15 Drilling ( 6 mm carbide + TiN drill): For 6 mm drilling, the poor chip breakability of 436 does not appear to create any difficulties in terms of reducing the optimum working area or the useful life of the tools, as the 436 grade behaves better than UGIMA 444 with respect to these two parameters, irrespective of whether or not the HM version is used. Caution: the surface condition of the drilled holes may be of inferior quality, due to poor chip breakability "Monobloc carbide" drilling (6 mm diameter) 45N N L - IMA L - IMA444HM ** Max. chip flow for 516 holes 4 mm deep using the same drill. Screw machining: Straight turning: confirms the very good behaviour of 436 in turning operations, which is better than that of UGIMA 444 in this case. "High-speed steel" screw machining/drilling (4 mm diameter) Drilling with a 4 mm high-speed steel drill: confirms the difficulty of chip removal due to the poor chip breakability of 436 in the absence of central cooling compared with UGIMA 444 HM.,5 1,5 1,5 45N N L - IMA L - IMA444HM Cross-cutting: intermediate behaviour between UGIMA 444 HM and 446 (see the table below). *** Max chip flow for tool behaviour for 7 screw-machined components. Optimum cross-cutting conditions for 1 mm bars for cross-cutting 7 components with the same tool. 45N (1) 35N (1) Test Speed (m/min) Feed (mm/rev) Speed (m/min) Feed (mm/rev) Cross-cutting 6.4 /.15.5 /.5 Useful life L UGIMA 444 () 316L UGIMA 444 HM () Test Speed (m/min) Feed (mm/rev) Speed (m/min) Feed (mm/rev) Cross-cutting 14.5 / /.35 Useful life (1) Sandvik 135 (N151.--SE); () Iscar IC38 GFN J 7343 UGINE Cedex - France 5

6 .3 1., 3,5 5, ,15 Welding may be welded by friction, by electrical resistance, by electric arc with or without filler metal TIG, MIG, electrode, plasma, under flux ), by laser beam, by electron beam.. The low Mo content of the grade,precludes sigma phase formation in welding operations, unlike other duplex stainless steels which require precautions. Welding is therefore straightforward, and not much more complex than that of austenitic grades such as 34L (437) or 316L (444). Duplex is even better as far as hot-cracking is concerned. However, in order to optimize the impact properties of the welds, the welding conditions should maximize the welding energy in order to limit the amount of ferrite in the molten zone and in the heat affected zone. Various filler metal grades may be used to weld, depending on the mechanical properties and the corrosion resistance required in the welds. The main ones are: ER9 /.9.3NL / SMArc 45N ER 39LSi / 3.1LSi / SMArc 39LM Preheating of the parts before welding is not necessary. No post weld heat treatment is required and should be carried out, with the possible exception of a complete solution anneal, if required. Products available products Form Finishing Tolerance Size (mm) Bars Hot Rolled, desalled 13 Bars cold drawing, turned, ground, Bright 6 à 11 Wire Rod round 5.5 ø 3 mm Drawn wire Others: Please contact us Applications Generally speaking, wherever 316 & 316L (441 &444) are used. Energy & Process industries Construction Food processing Limitations of use: Cryogenic Applications (low toughness at cryogenic temperatures) Service temperatures exceeding 3 C In case of doubt, please enquire UGINE Cedex - France 6