US20070089810A1 - Duplex stainless steel alloy for use in seawater applications - Google Patents

Duplex stainless steel alloy for use in seawater applications Download PDF

Info

Publication number
US20070089810A1
US20070089810A1 US10/547,572 US54757204A US2007089810A1 US 20070089810 A1 US20070089810 A1 US 20070089810A1 US 54757204 A US54757204 A US 54757204A US 2007089810 A1 US2007089810 A1 US 2007089810A1
Authority
US
United States
Prior art keywords
weight
content
alloy according
alloy
ferrite
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/547,572
Other languages
English (en)
Inventor
Ann Sundstrom
Pasi Kangas
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sandvik Intellectual Property AB
Original Assignee
Sandvik Intellectual Property AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sandvik Intellectual Property AB filed Critical Sandvik Intellectual Property AB
Assigned to SANDVIK INTELLECTUAL PROPERTY AB reassignment SANDVIK INTELLECTUAL PROPERTY AB ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SUNDSTROM, ANN, KANGAS, PASI
Publication of US20070089810A1 publication Critical patent/US20070089810A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/52—Ferrous alloys, e.g. steel alloys containing chromium with nickel with cobalt
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/54—Ferrous alloys, e.g. steel alloys containing chromium with nickel with boron

Definitions

  • the present invention relates to a stainless steel alloy, more precisely a duplex stainless steel alloy having ferritic-austenitic matrix and having high corrosion resistance in combination with good structural stability and hot workability, in particular a duplex stainless steel having a ferrite content of 40-65% by volume and a well-balanced composition that gives the material corrosion properties making it more suitable able for use in chloride-containing environments than what has previously been found possible.
  • Valves and couplings on the unit at the bottom of the sea are controlled hydraulically and electrically from a platform, a production ship or another unit on the surface of the sea or on land.
  • An umbilical cord pipe a so-called umbilical, couples together the guiding unit with the units on the bottom of the sea.
  • the part of the umbilical that lies on the bottom of the sea, for instance, between two underwater units on different extraction sites, is called static umbilical since the same only to a relatively small extent is effected by the motions of the sea.
  • the part of the umbilical, that is situated between the bottom of the sea and the surface is called dynamic umbilical and is effected to a large extent by motions in the water and on the surface. Examples of such motions are flows in the water, wave motions as well as motions of the platform and the production ship.
  • the demands that are made on the pipes in an umbilical are foremost related to corrosion and mechanical properties.
  • the pipe material has to be resistant to corrosion in sea water, which surrounds the outer surface of the pipes. This property is what is regarded as being most important, since sea water has a very corrosive impact on stainless steel.
  • the material has to have high corrosion resistance to the possible corrosive solutions that are injected in the oil well.
  • the material has to be compatible with hydraulic liquids without contaminating the liquid. Possible contamination may affect the service function of the control unit at the bottom of the sea very negatively.
  • the mechanical properties of the used pipe material are very important for the application of umbilical pipes. Since the depth may be considerable on the site of the oil production, the dynamic part of the umbilical generally becomes long, and thereby heavy. The weight has to be carried by the platform or the floating production ship. In practice, there is two ways to decrease the weight of an umbilical having a given configuration. It is possible to choose a lighter material or a material having the same density but having higher tensile yield limit and ultimate tensile strength. By choosing a material having higher strength, pipes having thinner wall may be used, and thereby the total mass of the umbilical is reduced. The deeper the sea at the site of extraction, the more important the total weight per unit of length of umbilical of the material will be.
  • Duplex steel alloys that were established as an alternative to hitherto used types of steel, such as, for instance, ferritic steel that previously were used in this application, nickel base alloys or other high-alloy steels, are not excepted from this development.
  • PRE Pitting Resistance Equivalent
  • the principal alloying elements that affect this property are, according to the formula, Cr, Mo, N.
  • An example of such a steel grade is seen in EP 0 220 141, which through this reference hereby is included in this description.
  • This steel grade, having the trade mark of SAF 2507 (UNS S32750), has essentially been alloyed with high contents of Cr, Mo and N. Thus, it is developed towards this property with, above all, good corrosion resistance in chloride environments.
  • the elements Cu and W have turned out to be efficient alloying additives for additional optimization of the corrosion properties of the steel in chloride environments.
  • the element W has, on that occasion, been used as substitution for a part of Mo, as for instance in the commercial alloys DP3W (UNS S39274) or Zeron100, which contain 2.0% and 0.7% of W, respectively.
  • the latter also contains 0.7% of Cu with the purpose of increasing the alloy's corrosion resistance in acid environments.
  • the above-described steel grades have a PRE number, irrespective of method of calculation, which is above 40 but the PRE number is limited upwards to about 43 since higher values mean that the alloys obtain inferior structural stability.
  • a higher degree of alloying increases the risk of precipitation of internietallic phase, and therefore the level of alloying in duplex steel is regarded as limited to achieve PRE values around a maximum of about 43, irrespective of method of calculation.
  • the alloy has a corrosion resistance in chloride environment corresponding to the alloy UNS S32750, but simultaneously a higher yield point in tension Rp 0.2 . This makes that this alloy has advantages in comparison with UNS S32750 as umbilical material, since lower weight of the umbilical can be obtained.
  • the corrosion resistance gives, however, no improvements in comparison with UNS S32750, which means considerable limitations in umbilical pipes that are exposed to higher temperatures in future plants.
  • the alloy 19D (UNS S32001) is a duplex alloy characterized by the composition 19.5-21.5% of Cr, 0.05-0.17% of N and max 0.6% of Mo.
  • This alloy has a PRE number of about 22, and therefore the alloy is unsuitable in sea-water applications such as umbilicals. Accordingly, in order to achieve a sufficient corrosion resistance in this alloy, a cathode protection has to be applied in the form of a zinc layer on the outer surface of the umbilical pipe. If the zinc layer is consumed or if a greater surface becomes damaged, the corrosion protection is, however, ruined and a fast corrosion process may occur, which means expensive repairs and down periods.
  • austenitic steels with PRE numbers of up to 55 having been made possible by the addition of high contents of Cr, Mo and NJ combined with high contents of Ni.
  • Said alloys should work very well to the new tougher corrosion conditions in umbilicals.
  • the disadvantage of the same alloys is that they have considerably lower yield point in tension than duplex steel and are, furthermore, considerably more expensive to manufacture, foremost by virtue of their high percentage of Ni, which is an expensive alloying material.
  • austenites having good resistance in chloride environment are UNS S32654 having a PRE number of about 55, and UNS S34565 having a PRE number of about 45. These have, however, too low a strength and high a cost in order to be a realistic alternative for umbilical pipes.
  • the pitting resistance of duplex stainless steel an increase of the PRE number is required in both the ferrite phase and the austenite phase without, because of this, jeopardizing the structural stability or the workability of the material. If the composition in the two phases is not equivalent in respect of the active alloying components, one of the phases becomes more susceptible to pitting and crevice corrosion. Thus, the more corrosion-susceptible phase controls the resistance of the alloy, while the structural stability is controlled by the highest alloyed phase.
  • CPT Critical Pitting Corrosion Temperature
  • CCT Critical Crevice Corrosion Temperature
  • the material according to the present invention has, in view of the high alloy content thereof, extraordinarily good workability, in particular hot-workability, and should thereby be very suitable to be used for, for instance, the manufacture of bars, pipes, such as welded and seamless pipes, weld material, construction parts such as, for instance, flanges and couplings.
  • duplex stainless steel alloys which contain (in % by weight) C more than 0 up to max 0.03% Si up to max 0.5% Mn 0-3.0% Cr 24.0-30.0% Ni 4.9-10.0% Mo 3.0-5.0% N 0.28-0.5% B 0-0.0030% S up to max 0.010% Co 0-3.5% W 0-3.0% Cu 0-2.0% Ru 0-0.3% Al 0-0.03% Ca 0-0.010% balance Fe together with inevitable contaminations.
  • FIG. 1 shows CPT values from test of the experimental charges in the modified ASTM G48C test in the “Green Death” solution in comparison with the duplex steels SAF 2507, SAF 2906.
  • FIG. 2 shows CPT values produced by means of the modified ASTM G48C test in “Green Death” solution for the experimental charges in comparison with the duplex steel SAF 2507 as well as SAF 2906.
  • FIG. 3 shows the mean value of the corrosion in mm/year in 2% HCl at the temperature of 75° C.
  • FIG. 4 shows the results from hot ductility test for most of the charges.
  • the alloy according to the invention contains (in % by weight): C more than 0 up to max 0.03% Si up to max 0.5% Mn 0-3.0% Cr 24.0-30.0% Ni 4.9-10.0% Mo 3.0-5.0% N 0.28-0.5% B 0-0.0030% S up to max 0.010% Co 0-3.5% W 0-3.0% Cu 0-2.0% Ru 0-0.3% Al 0-0.03% Ca 0-0.010% balance Fe together with normally occurring contaminations and additives, the ferrite content being 40-65% by volume.
  • Carbon (C) has limited solubility in both ferrite and austenite.
  • the limited solubility means a risk of precipitation of chromium carbides and therefore the content should not exceed 0.03% by weight, preferably not exceed 0.02% by weight.
  • Si Silicon
  • Si is utilized as deoxidizer in the steel production and increases the flowability in production and upon welding.
  • too high contents of Si lead to precipitation of undesired intermetallic phase, and therefore the content should be limited to max 0.5% by weight, preferably max 0.3% by weight.
  • Manganese (Mn) is added in order to increase the solubility of N in the material.
  • Mn only has a limited impact on the solubility of N in the alloy type in question. Instead, there are other elements having higher impact on the solubility.
  • Mn may in combination with high sulphur contents give rise to the formation of manganese sulphides, which work as initiation spots for pitting. Therefore, the content of Mn should be limited to between 0-3.0% by weight, preferably 0.5-1.2% by weight.
  • Chromium (Cr) is a very active element in order to improve the resistance to the majority of corrosion types. Furthermore, a high chromium content means that a very good solubility of N is obtained in the material. Thus, it is desirable to hold the content of Cr as high as possible in order to improve the corrosion resistance. For very good values of the corrosion resistance, the chromium content should be at least 24.0% by weight, preferably 27.0-29.0% by weight. However, high contents of Cr increases the risk of intermetallic precipitations, and therefore the chromium content has to be limited upwards to max 30.0% by weight.
  • Nickel (Ni) is used as austenite-stabilizing element and is added in suitable contents so that the desired ferrite content is attained.
  • an addition of between 4.9-10.0% by weight of nickel is required, preferably 4.9-9.0% by weight, in particular 6.0-9.0% by weight.
  • Molybdenum (Mo) is an active element that improves the corrosion resistance in chloride environments as well as preferably in reducing acids. Too high a content of Mo, in combination with the contents of Cr being high, means that the risk of intermetallic precipitations increases.
  • the content of in the present invention should be in the interial of 3.0-5.0% by weight, preferably 3.6-4.9% by weight, in particular 4.4-4.9% by weight.
  • N Nitrogen
  • N is a very active element that increases the corrosion resistance, the structural stability as well as the strength of the material. Furthermore, a high content of N improves the reformation of austenite after welding, which gives good properties of welded joints. In order to achieve a good effect from N, at least 0.28% by weight of N should be added. At high contents of N, the risk of precipitation of chromium nitrides increases, especially when the chromium content simultaneously is high. Furthermore, a high content of N means that the risk of porosity increases by virtue of the solubility of N in the charge being exceeded. The content of N should, for these reasons, be limited to max 0.5% by weight, preferably is >0.35-0.45% by weight of N added.
  • Boron (B) is added in order to increase the hot workability of the material. At too high a boron content, the weldability and the corrosion resistance may be deteriorated. Therefore, the boron content should be greater than 0 and up to 0.0030% by weight.
  • S Sulphur
  • S Sulphur
  • Co Co
  • Co is added foremost in order to improve the structural stability as well as the corrosion resistance.
  • Co is an austenite stabilizer.
  • at least 0.5% by weight preferably at least 1.0% by weight should be added. Since cobalt is a relatively expensive element, the cobalt addition is therefore limited to max 3.5% by a weight.
  • Tungsten increases the resistance to pitting and crevice corrosion. But addition of too high contents of tungsten in combination with the contents of Cr and contents of Mo being high, means that the risk of intermetallic precipitations increases.
  • the content of W in the present invention should be in the interval of 0-3.0% by weight, preferably between 0-1.8% by weight.
  • Copper is added in order to improve the corrosion resistance in acid environments such as sulphuric acid. Cu also affects the structural stability. However, high contents of Cu means that the solid solubility is exceeded. Therefore, the content of Cu is limited to max 2.0% by weight, preferably between 0.1 and 1.5% by weight.
  • Ruthenium (Ru) is added in order to increase the corrosion resistance. Ruthenium is a very expensive element, and therefore the content is limited to max 0.3% by weight, preferably greater than 0 and up to 0.1% by weight.
  • Aluminum (Al) as well as Calcium (Ca) are utilized as deoxidizers in the steel production.
  • the content of Al should be limited to max 0.03% by weight in order to limit nitride formation.
  • Ca has a favourable effect on the hot ductility but the content of Ca should, however, be limited to 0.010% by weight in order to avoid undesired quantity of cinder.
  • the ferrite content is important in order to obtain good mechanical properties and corrosion properties as well as good weldability. From a corrosion and a weldability point of view, it is desirable having a ferrite content of between 40-65% in order to obtain good properties. Furthermore, high ferrite contents means that the low-temperature impact resistance as well as the resistance to hydrogen embrittlement risk being deteriorated. Therefore, the ferrite content is 40-65% by volume, preferably 42-60% by volume, in particular 45-55% by volume.
  • Experimental charges according to this example were produced by laboratory casting of 170 kg of ingot that was hot-forged into round bar. The same was hot extruded into bar (round bar as well as flat bar), where test material was sampled from round bar. Furthermore, flat bar was annealed before cold rolling took place, and then additional test material was sampled. The process may, from a material technology point of view, be regarded as representative for the manufacture on a larger scale, for instance for the manufacture of seamless pipes by means of the extrusion method followed by cold rolling. Table 2 shows composition of experimental charges of the first batch.
  • T max sigma is calculated by means of Thermo-Calc (T-C version N the thermodynamic database of steel TCFE99) based on guiding values of all stated elements in the different variants.
  • T max sigma is the resolution temperature of the sigma phase, with high resolution temperature indicating lower structural stability.
  • Tmax ⁇ 605193 1100° C., 5 min 7.5% 1016 605195 1150° C., 5 min 32% 1047 605197 1100° C., 5 min 18% 1061 605178 1100° C., 5 min 14% 1038 605183 1050° C., 5 min 0.4% 997 605184 1100° C., 5 min 0.4% 999 605187 1050° C., 5 min 0.3% 962 605153 1100° C., 5 min 3.5% 1032 605182 1100° C., 5 min 2.0% 1028
  • the object of this investigation is to be able to rank materials in respect of the structural stability, i.e. this is not the actual content of sigma phase in the test pieces that have been heat treated and quenched before, for instance, corrosion test. It is evident that T max sigma that has been calculated by means of Thermo-calc does not directly corresponds with measured quantity of sigma phase, but in this investigation it is, however, clear that the experimental charges having the lowest calculated T max sigma contain the lowest quantity of sigma phase.
  • the pitting properties of all charges have been tested for ranking in the so-called “Green Dealth” solution that consists of 1% FeCl 3 , 1% CuCl 2 , 11% H 2 SO 4 , 12% HCl.
  • the test procedure corresponds to the pitting testing according to ASTM G48C, but is carried out in the more aggressive “Green Death” solution.
  • some charges have been tested according to ASTM G48C (2 experiments per charge).
  • electrochemical testing in 3% NaCl (6 experiments per charge) has been carried out.
  • the results in the form of critical pitting temperature (CPT) from all experiments are seen in Table 4, such as the PREW number (Cr+3.3(Mo+0.5W)+16 N) of the total alloy composition as well as of austenite and ferrite.
  • the indexing alpha relates to ferrite and gamma relates to austenite.
  • CPT ° C. Modified CPT ° C. ASTM CPT ° C. 3% ASTM G48C G48C 6% NaCl (600 mv Charge PRE ⁇ PRE ⁇ PRE ⁇ /PRE ⁇ PRE Green Death FeCl 3 SCE 605193 51.3 49.0 0.9552 46.9 90/90 64 605195 51.5 48.9 0.9495 48.7 90/90 95 605197 53.3 53.7 1.0075 50.3 90/90 >95 >95 605178 50.7 52.5 1.0355 49.8 75/80 94 605183 48.9 48.9 1.0000 46.5 85/85 90 93 605184 48.9 51.7 1.0573 48.3 80/80 72 605187 48.0 54.4 1.1333 48.0 70/75 77 605153 49.6 51.9 1.0464 48.3 80/85 85 90 605182 54.4 46.2 0.8493 46.6 75/70 85
  • Test charge 605 183 alloyed with cobalt shows good structural stability at controlled cooling rate ( ⁇ 140° C./min), in spite of it containing high contents of chromium as well as molybdenum, has better results than SAF 2507 as well as SAF 2906.
  • the strength at room temperature (RT), 100° C. and 200° C. and the impact resistance at room temperature (RT) have been determined for all charges and are shown as mean value of three experiments.
  • Tensile test pieces were produced from extruded bars ⁇ 20 mm, which were heat treated at temperatures according to Table 2 for 20 min followed by cooling down in either air or water (605 195, 605 197, 605 184). The results of the investigation are presented in Tables 5 and 6. The results of the tensile strength investigation show that the contents of chromium, nitrogen and tungsten strongly affect the tensile strength in the material. All charges except 605 153 meet the requirement on a 25% elongation upon tensile testing at room temperature (RT).
  • Table 7 shows results from Tungsten Inert Gas remelting test (henceforth abbreviated TIG), with the charges 605 193, 605 183, 605 184 as well as 605 253 having a stable structure in the heat affected zone (henceforth abbreviated HAZ).
  • TIG Tungsten Inert Gas remelting test
  • HAZ heat affected zone
  • the composition is given of an additional number of experimental charges manufactured with the intention of finding the optimal composition. Said charges are modified, based on the properties of the charges having good structural stability as well as high corrosion resistance, from the results that were shown in Example 1. All charges in Table 8 are comprised of the composition according to the present invention, with charges 1-8 being included in a statistical experimental plan, while charges e to n are additional experimental alloys within the scope of this invention.
  • the pitting properties of all charges have been tested in the “Green Death” solution (1% FeCl 3 , 1% CuCl 2 , 11% H 2 SO 4 , 1.2% HCl) for ranking.
  • the test procedure is the same as pitting testing according to ASTM G48C, but the testing is carried out in a more aggressive solution than 6% FeCl 3 , the so-called “Green Death” solution.
  • general corrosion test in 2% HCl (2 experiments per charge) has been carried out for ranking before dew point testing. The results from all experiments are seen in Table 10, FIG. 2 and FIG. 3 . All tested charges perform better than SAF 2507 in the Green Death solution.
  • the samples were annealed for 20 min at 1080° C., 1100° C. and 1150° C., and then they were quenched in water.
  • the temperature where the amount of intermetallic phase became negligibly small was determined by means of investigations in light-optical microscope.
  • a comparison of the structure of the charges after annealing at 1080° C. followed by water quenching indicates which of the charges that are more inclined to contain undesired sigma phase.
  • the results are seen in Table 11.
  • Structural control shows that the charges 605 249, 605 251, 605 252, 605 253, 605 254, 605 255, 605 259, 605 260, 605 266 as well as 605 267 are free from undesired sigma phase.
  • charge 605 249 alloyed with 1.5% by weight of cobalt
  • charge 605 250 alloyed with 0.6% by weight of cobalt
  • Both charges are alloyed with high percentage of chromium, almost 29.0% by weight, as well as molybdenum content of almost 4.25% by weight.
  • charge 605 268 contains only occasional sigma phase in comparison with charge 605 263, which contains much sigma phase. What essentially separates these charges, is addition of copper to charge 605 268. In charge 605 266 as well as 605 267, the sigma phase is free in spite of high chromium content, the later charge is alloyed with copper. Furthermore, the charges 605 262 and 605 263, having the addition of 1.0% by weight of tungsten, have a structure with much sigma phase, while it is interesting to note that charge 605 269, also having 1.0% by weight of tungsten but of a higher nitrogen content than 605 262 and 605 263, has a considerably smaller quantity of sigma phase. Thus, a very well-adjusted balance between the various alloying elements is required at these high alloy contents for, e.g., chromium and molybdenum, in order to obtain good structural properties.
  • Table 12 shows the results from the light optical investigation after annealing at 1080° C., 20 min, followed by water quenching.
  • the amount of sigma phase is indicated by means of values from 1 to 5, with 1 representing that no sigma phase has been detected upon the investigation, while 5 representing that a very high percentage of sigma phase has been detected upon the investigation.
  • FIG. 4 shows the results from hot ductility test of most of the charges.
  • a good workability is naturally crucial in order to be able to manufacture the material into product shapes such as bars, pipes, such as welded and seamless pipes, thread, weld material, construction parts such as, for instance, flanges and couplings.
  • the strain controlled fatigue properties give information about how much, and how many times, a material may be elongated, before strain controlled fatigue cracks arise in the material. Since umbilical pipes are welded together into long lengths, are reeled on drums before the are twisted into the umbilical, it is not unusual that a number of operations occurs where certain plastic deformation arises before the umbilical starts function.
  • the strain controlled fatigue data that has been established emphasize that the risk of rupture as a consequence of strain controlled fatigue in an umbilical pipe borders on zero.
  • the strength that is required for being able to substantially reduce the weight of an umbilical is: Yield point in tension Rp 0.2 min 720 N/mm 2
  • the material according to the present invention has, in view of the high alloys content thereof, extraordinarily good workability, in particular hot-workability, and should thereby be very suitable to be used for, for instance, the manufacture of bars, pipes, such as welded and weldless pipes, weld material, construction parts, such as, for instance, flanges and couplings.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)
  • Heat Treatment Of Articles (AREA)
  • Arc Welding In General (AREA)
US10/547,572 2003-03-02 2004-02-19 Duplex stainless steel alloy for use in seawater applications Abandoned US20070089810A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
SE0300574A SE527178C2 (sv) 2003-03-02 2003-03-02 Användning av en duplex rostfri stållegering
SE0300574-1 2003-03-02
PCT/SE2004/000223 WO2004079027A1 (en) 2003-03-02 2004-02-19 Duplex stainless steel alloy for use in seawater applications

Publications (1)

Publication Number Publication Date
US20070089810A1 true US20070089810A1 (en) 2007-04-26

Family

ID=20290561

Family Applications (1)

Application Number Title Priority Date Filing Date
US10/547,572 Abandoned US20070089810A1 (en) 2003-03-02 2004-02-19 Duplex stainless steel alloy for use in seawater applications

Country Status (11)

Country Link
US (1) US20070089810A1 (enExample)
EP (1) EP1599612A1 (enExample)
JP (1) JP2006519313A (enExample)
KR (1) KR20060056886A (enExample)
CN (1) CN100457953C (enExample)
AU (1) AU2004217572A1 (enExample)
CA (1) CA2519786A1 (enExample)
EA (1) EA009108B1 (enExample)
NO (1) NO20054105L (enExample)
SE (1) SE527178C2 (enExample)
WO (1) WO2004079027A1 (enExample)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100012232A1 (en) * 2008-07-11 2010-01-21 Baker Hughes Incorporated Pitting corrosion resistant non-magnetic stainless steel
US20100316522A1 (en) * 2006-10-30 2010-12-16 Sandvik Intellectual Property Ab Duplex stainless steel alloy and use of this alloy
US20140003989A1 (en) * 2011-03-10 2014-01-02 Shinnosuke Kurihara Duplex stainless steel
US9803267B2 (en) 2011-05-26 2017-10-31 Upl, L.L.C. Austenitic stainless steel
US9816163B2 (en) 2012-04-02 2017-11-14 Ak Steel Properties, Inc. Cost-effective ferritic stainless steel
US11566301B2 (en) 2016-09-02 2023-01-31 Jfe Steel Corporation Dual-phase stainless steel, and method of production thereof

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008179844A (ja) * 2007-01-23 2008-08-07 Yamaha Marine Co Ltd 二相ステンレス鋼及び二相ステンレス鋼製鋳造品
CN101704168B (zh) * 2009-09-24 2012-01-18 江苏大学 一种耐空泡腐蚀的表面堆焊焊接材料
SE534779C2 (sv) 2010-03-03 2011-12-20 Sandvik Intellectual Property Metod för att tillverka en trådprodukt av rostfritt stål
JP5609668B2 (ja) * 2011-01-20 2014-10-22 Ｊｆｅスチール株式会社 耐海水孔食性に優れたステンレスクラッド鋼
CN102191426B (zh) * 2011-04-14 2013-08-28 山西太钢不锈钢股份有限公司 焊接用不锈钢线材及其线材用钢的冶炼方法
FI125854B (fi) * 2011-11-04 2016-03-15 Outokumpu Oy Dupleksi ruostumaton teräs
US9347121B2 (en) * 2011-12-20 2016-05-24 Ati Properties, Inc. High strength, corrosion resistant austenitic alloys
WO2015109553A1 (zh) * 2014-01-25 2015-07-30 吴津宁 一种双相不锈钢无缝钢管
BR102014005015A8 (pt) * 2014-02-28 2017-12-26 Villares Metals S/A aço inoxidável martensítico-ferrítico, produto manufaturado, processo para a produção de peças ou barras forjadas ou laminadas de aço inoxidável martensítico-ferrítico e processo para a produção de tudo sem costura de aço inoxidável martensítico-ferrítico
CN104004971B (zh) * 2014-05-09 2016-02-03 无锡市华尔泰机械制造有限公司 一种合金材料法兰及其锻造工艺
JP7144418B2 (ja) * 2016-12-21 2022-09-29 サンドビック インテレクチュアル プロパティー アクティエボラーグ 二相ステンレス鋼物体の使用
PL3502293T3 (pl) * 2017-12-22 2020-11-02 Saipem S.P.A. Zastosowania dupleksowych stali nierdzewnych
CN108396257B (zh) * 2018-02-08 2020-01-21 中国兵器科学研究院宁波分院 一种控制析出法制备海洋平台用超级双相不锈钢阀门的方法
CN109187322B (zh) * 2018-08-31 2021-03-12 南京钢铁股份有限公司 一种极地海洋环境用低合金钢的耐蚀性评价方法
CN109266957A (zh) * 2018-09-18 2019-01-25 无锡市华尔泰机械制造有限公司 改进型z2cnd18-12n材料法兰及其锻造方法
CN111020368B (zh) * 2019-10-30 2021-07-20 鞍钢股份有限公司 一种海水淡化用双相不锈钢复合钢板及其制造方法
CN112410675A (zh) * 2020-11-20 2021-02-26 齐鲁工业大学 稀土双相耐蚀铸造不锈钢及其制造方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5238508A (en) * 1984-02-07 1993-08-24 Kubota, Ltd. Ferritic-austenitic duplex stainless steel
US5298093A (en) * 1991-11-11 1994-03-29 Sumitomo Metal Indusries, Ltd. Duplex stainless steel having improved strength and corrosion resistance
US5582656A (en) * 1993-06-21 1996-12-10 Sandvik Ab Ferritic-austenitic stainless steel
US5733387A (en) * 1995-06-05 1998-03-31 Pohang Iron & Steel Co., Ltd. Duplex stainless steel, and its manufacturing method
US20010031217A1 (en) * 2000-03-02 2001-10-18 Orjan Bergstrom Duplex stainless steel
US20030086808A1 (en) * 2001-09-02 2003-05-08 Ann Sundstrom Duplex stainless steel alloy
US20030133823A1 (en) * 2001-09-02 2003-07-17 Ann Sundstrom Use of a duplex stainless steel alloy

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE453838B (sv) * 1985-09-05 1988-03-07 Santrade Ltd Hogkvevehaltigt ferrit-austenitiskt rostfritt stal
AT397515B (de) * 1990-05-03 1994-04-25 Boehler Edelstahl Hochfeste korrosionsbeständige duplex-legierung
JP3227734B2 (ja) * 1991-09-30 2001-11-12 住友金属工業株式会社 高耐食二相ステンレス鋼とその製造方法
CN1052036C (zh) * 1994-05-21 2000-05-03 朴庸秀 有高耐腐蚀性的双相不锈钢
JP3588826B2 (ja) * 1994-09-20 2004-11-17 住友金属工業株式会社 高窒素含有ステンレス鋼の熱処理方法
JPH09209087A (ja) * 1996-02-01 1997-08-12 Sumitomo Metal Mining Co Ltd 二相ステンレス鋼
JPH09279313A (ja) * 1996-04-15 1997-10-28 Sumitomo Metal Ind Ltd 都市ゴミ焼却設備排ガス系用ステンレス鋼
CN1068385C (zh) * 1996-10-14 2001-07-11 冶金工业部钢铁研究总院 超低碳双相不锈钢及其制造方法
AT405297B (de) * 1997-08-13 1999-06-25 Boehler Edelstahl Duplexlegierung für komplex beanspruchte bauteile
SE513247C2 (sv) * 1999-06-29 2000-08-07 Sandvik Ab Ferrit-austenitisk stållegering
JP3758508B2 (ja) * 2001-02-13 2006-03-22 住友金属工業株式会社 二相ステンレス鋼管の製造方法

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5238508A (en) * 1984-02-07 1993-08-24 Kubota, Ltd. Ferritic-austenitic duplex stainless steel
US5298093A (en) * 1991-11-11 1994-03-29 Sumitomo Metal Indusries, Ltd. Duplex stainless steel having improved strength and corrosion resistance
US5582656A (en) * 1993-06-21 1996-12-10 Sandvik Ab Ferritic-austenitic stainless steel
US5733387A (en) * 1995-06-05 1998-03-31 Pohang Iron & Steel Co., Ltd. Duplex stainless steel, and its manufacturing method
US20010031217A1 (en) * 2000-03-02 2001-10-18 Orjan Bergstrom Duplex stainless steel
US6749697B2 (en) * 2000-03-02 2004-06-15 Sandvik Ab Duplex stainless steel
US20030086808A1 (en) * 2001-09-02 2003-05-08 Ann Sundstrom Duplex stainless steel alloy
US20030133823A1 (en) * 2001-09-02 2003-07-17 Ann Sundstrom Use of a duplex stainless steel alloy

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100316522A1 (en) * 2006-10-30 2010-12-16 Sandvik Intellectual Property Ab Duplex stainless steel alloy and use of this alloy
US20100012232A1 (en) * 2008-07-11 2010-01-21 Baker Hughes Incorporated Pitting corrosion resistant non-magnetic stainless steel
US8535606B2 (en) 2008-07-11 2013-09-17 Baker Hughes Incorporated Pitting corrosion resistant non-magnetic stainless steel
US20140003989A1 (en) * 2011-03-10 2014-01-02 Shinnosuke Kurihara Duplex stainless steel
US9512509B2 (en) * 2011-03-10 2016-12-06 Nippon Steel & Sumitomo Metal Corportion Duplex stainless steel
US9803267B2 (en) 2011-05-26 2017-10-31 Upl, L.L.C. Austenitic stainless steel
US9816163B2 (en) 2012-04-02 2017-11-14 Ak Steel Properties, Inc. Cost-effective ferritic stainless steel
US11566301B2 (en) 2016-09-02 2023-01-31 Jfe Steel Corporation Dual-phase stainless steel, and method of production thereof

Also Published As

Publication number Publication date
NO20054105D0 (no) 2005-09-02
CA2519786A1 (en) 2004-09-16
CN1768156A (zh) 2006-05-03
JP2006519313A (ja) 2006-08-24
EP1599612A1 (en) 2005-11-30
SE527178C2 (sv) 2006-01-17
KR20060056886A (ko) 2006-05-25
WO2004079027A1 (en) 2004-09-16
EA009108B1 (ru) 2007-10-26
AU2004217572A1 (en) 2004-09-16
NO20054105L (no) 2005-09-27
SE0300574L (sv) 2004-09-03
EA200501409A1 (ru) 2006-04-28
SE0300574D0 (sv) 2003-03-02
CN100457953C (zh) 2009-02-04

Similar Documents

Publication Publication Date Title
US20070089810A1 (en) Duplex stainless steel alloy for use in seawater applications
EP0708845B1 (en) Ferritic-austenitic stainless steel and use of the steel
US6749697B2 (en) Duplex stainless steel
EP1423548B1 (en) Duplex steel alloy
EP1423549B1 (en) Use of a duplex stainless steel alloy
US20100316522A1 (en) Duplex stainless steel alloy and use of this alloy
AU2002328002A1 (en) Duplex steel alloy
US20100084121A1 (en) Plate
US7892366B2 (en) Duplex stainless steel alloy and use thereof
US6451133B1 (en) Stainless steel for use in seawater applications
JPH08134593A (ja) 耐海水腐食性と耐硫化水素腐食性に優れた高強度オーステナイト合金
EP0320548B1 (en) Method of making a duplex stainless steel and a duplex stainless steel product with improved mechanical properties

Legal Events

Date Code Title Description
AS Assignment

Owner name: SANDVIK INTELLECTUAL PROPERTY AB, SWEDEN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SUNDSTROM, ANN;KANGAS, PASI;REEL/FRAME:018034/0784;SIGNING DATES FROM 20050902 TO 20050905

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION