EP1740733B1 - Iron-chrome-aluminum alloy - Google Patents

Iron-chrome-aluminum alloy Download PDF

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Publication number
EP1740733B1
EP1740733B1 EP05746889A EP05746889A EP1740733B1 EP 1740733 B1 EP1740733 B1 EP 1740733B1 EP 05746889 A EP05746889 A EP 05746889A EP 05746889 A EP05746889 A EP 05746889A EP 1740733 B1 EP1740733 B1 EP 1740733B1
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max
aluminium alloy
iron
alloy according
mass
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German (de)
French (fr)
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EP1740733A2 (en
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Heike Hattendorf
Angelika Kolb-Telieps
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VDM Metals GmbH
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ThyssenKrupp VDM GmbH
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
    • B01J35/56—Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
    • 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
    • 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
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • 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
    • C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • 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
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • 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
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/16—Selection of particular materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2370/00—Selection of materials for exhaust purification
    • F01N2370/02—Selection of materials for exhaust purification used in catalytic reactors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/28—Construction of catalytic reactors
    • F01N3/2803—Construction of catalytic reactors characterised by structure, by material or by manufacturing of catalyst support
    • F01N3/2807—Metal other than sintered metal

Definitions

  • the invention relates to a melt-metallurgically produced iron-chromium-aluminum alloy with a long service life.
  • Such alloys are used to make electrical heating elements and catalyst supports. These materials form a dense, adherent alumina layer that protects them from destruction at high temperatures (eg up to 1400 ° C). This protection is improved by additions of so-called reactive elements such as Ca, Ce, La, Y, Zr, Hf, Ti, Nb, W, which inter alia improve the adhesion of the oxide layer and / or reduce the layer growth, as for example in “ Ralf Bürgel, Handbook of High Temperature Materials Technology, Vieweg Verlag, Braunschweig 1998 "from page 274 is described.
  • the aluminum oxide layer protects the metallic material against rapid oxidation. At the same time she is growing herself, albeit very slowly. This growth takes place using consumption of the aluminum content of the material. If no aluminum is present, other oxides (chromium and iron oxides) grow, the metal content of the material is consumed very quickly and the material fails due to destructive corrosion. The time to failure is defined as the lifetime. An increase in the aluminum content prolongs the service life.
  • the WO 02/20197 is a ferritic stainless steel alloy, especially for use as Bankleiterelement known.
  • the alloy is formed by a powder metallurgy FeCrAl alloy comprising (in% by mass) less than 0.02% C, ⁇ 0.5% Si, ⁇ 0.2% Mn, 10.0 to 40.0% Cr, ⁇ 0.6% Ni, ⁇ 0.01% Cu, 2.0 to 10.0% Al, one or more element (s) from the group of reactive elements, such as Sc, Y, La, Ce, Ti, Zr, Hf, V, Nb, Ta, in contents between 0.1 and 1.0%, balance iron and unavoidable impurities.
  • DE-A 199 28 842 is an alloy with (in mass%) 16 to 22% Cr, 6 to 10% Al and additions of 0.02 to 1.0% Si, max. 0.5% Mn, 0.02 to 0.1% Hf, 0.02 to 0.1% Y, 0.001 to 0.01% Mg, max. 0.02% Ti, max. 0.03% Zr, max. 0.02% SE, max. 0.1% Sr, max. 0.1% Ca, max. 0.5% Cu, max. 0.1% V, max. 0.1% Ta, max. 0.1% Nb, max. 0.03% C, max. 0.01% N, max. 0.01% B, the remainder iron and impurities due to melting for use as a carrier film for catalytic converters, as a heating conductor, as a component in industrial furnace construction and in gas burners.
  • EP-B 0 290 719 is an alloy with (in mass%) 12 to 30% Cr, 3.5 to 8% Al, 0.008 to 0.10% carbon, max. 0.8% silicon, 0.10 to 0.4% manganese, max. 0.035% phosphorus, max. 0.020% sulfur, 0.1 to 1.0% molybdenum, max.
  • nickel 1% nickel, and the additives 0.010 to 1.0% zirconium, 0.003 to 0.3% titanium and 0.003 to 0.3% nitrogen, calcium plus magnesium 0.005 to 0.05%, and rare earth metals from 0.003 to 0.80 %, Niobium of 0.5%, remaining iron described with conventional accompanying elements, for example, as a wire for heating elements for electrically heated furnaces and as a construction material for thermally stressed parts and is used as a film for the preparation of catalyst supports.
  • US-A 4,414,023 is a steel with (in mass%) 8.0 to 25.0% Cr, 3.0 to 8.0% Al, 0.002 to 0.06% rare earth metals, max. 4.0% Si, 0.06 to 1.0% Mn, 0.035 to 0.07% Ti, 0.035 to 0.07% Zr, including unavoidable impurities.
  • t B 4 . 4 ⁇ 10 - 3 ⁇ C 0 - C B ⁇ ⁇ ⁇ d ⁇ k - 1 n ⁇ ⁇ ⁇ m * 1 n - 1 where ⁇ m * is the critical weight change at which the flakes begin.
  • Temperature cycles with a short heat-up time, a short cooling time and a Only short hold time at the high temperature are called short and fast temperature cycles in the following. These include z. B. Temperature cycles with a total duration in the range of several seconds to several minutes, where total duration is the sum of heating time, holding time at temperature, cooling time and waiting time until the beginning of the next heating is meant.
  • Heating conductors which consist of thin foils (for example, about 30 to 100 microns thick with a width in the range of one or more millimeters), are characterized by a large surface area to volume ratio. This is advantageous if you want to achieve fast heating and cooling times, as z. As required in the heating elements used in Ceranfeldern to let the heating quickly become visible and to achieve a rapid heating similar to a gas cooker. At the same time, however, the large surface area to volume ratio is disadvantageous for the service life of the heating conductor (see above). In addition, in this application, the temperature under the glass must be limited to protect it from damage. This can be achieved by repeated, momentary switching off of the current. Both have a burden of the heating by short heating times and rapid cooling and only short hold times result, which, as described above, further reduces the life.
  • Chromium-aluminum alloy with 20% Cr, 7% Al and additions of 0.04% yttrium, 0.05% Zr and 0.05% Ti It shifts the range in which an increased rate of oxidation by adding too much a reactive element occurs with the aluminum content. So caused after J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 0.04% Zr in an iron-chromium-aluminum alloy with 20% Cr, 7% Al and 0.05% Y already has an increased oxidation rate. The same amount of Zr in an iron-chromium-aluminum alloy containing 20% Cr, 5.5% Al and 0.05% Y and 0.05% Hf ( J. Klöwer, A.
  • the invention has for its object to provide an iron-chromium-aluminum alloy, which has a longer life than the previously used iron-chromium-aluminum alloys, especially for components with high surface area to volume ratio, or smaller band thickness.
  • the element Hf may be further replaced by at least one of the elements Sc and / or Ti and / or V and / or Nb and / or Ta and / or La and / or cerium wholly or partly, wherein at partial substitution ranges between 0 , 02 and 0.15 mass% are conceivable.
  • the alloy according to the invention with (in% by mass) max. 0.02% N, max. 0.02% P and max. 0.005% S are melted.
  • the iron-chromium-aluminum alloy according to the invention which with at least 0.1% Zr at min. 0.02% Y, in the above-mentioned cycles of 100 h and 96 h in the oven after J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 already show an increased oxidation rate and thus a shortened life, with a wire life test having a low surface to volume ratio, with the shorter cycle of 2 minutes "on” and 15 seconds “off” one at the upper end of the variation range of life
  • the alloy according to the prior art lifetime This difference becomes even more serious when passing the life test to 50 ⁇ m thick films that have a very high surface area to volume ratio and very short cycles of 15s "on” and 5s "off”.
  • Preferred Fe-Cr-Al alloys are characterized by the following composition (in% by mass): al 5 - 6% 5 - 6% Cr 18 - 22% 18 - 22% Si 0.05 - 0.7% 0.05 - 0.7% Mn 0.001 - 0.4% 0.001 - 0.4% Y 0.03 - 0.1% 0.03 - 0.1% Zr 0.15 - 0.25% Hf 0.02-0.15% 0.02 - 0.15% C 0.003 - 0.03% 0.003 - 0.3% mg 0.0002 - 0.03% 0.0002 - 0.03% Ca 0.0002 - 0.03% 0.0002 - 0.03% N Max. 0.04% Max. 0.04% P Max. 0.04% Max. 0.04% S Max. 0.01% Max. 0.01% Cu Max. 0.5% Max. 0.5%
  • the following elements can be set in their spreading ranges as follows: Hf 0.03 - 0.11% C 0.003 - 0.025% mg 0.0002 - 0.01% Ca 0.0002 - 0.01%
  • the alloy according to the invention is preferably usable for electrical heating elements, in particular with short heating and cooling times, short holding times to temperature and short waiting times until the beginning of a new heating.
  • the alloy according to the invention can also be used in heating elements which require high dimensional stability or low sagging.
  • the alloy according to the invention can also be used in heating conductors made of films having a thickness of from 20 to 100 ⁇ m.
  • Table 1 summarizes laboratory-molten iron-chromium aluminum alloys L1 to L8 and E1 to E6 and the large-scale molten alloys G1 to G3.
  • both wire and 50 ⁇ m thick film were produced from the material cast in blocks by means of hot and cold forming and suitable intermediate annealing. The film was cut into strips of 6 mm width.
  • For large-scale molten alloys a sample was taken from large-scale production at the strip thickness of 50 ⁇ m and, if necessary, cut to the appropriate width of approx. 6 mm.
  • the heat conductor life test is carried out on wires with a diameter of 0.40 mm from which wire coils with 12 turns, a coil diameter of 4 mm and a coil length of 50 mm.
  • the wire helices are clamped between 2 power supply lines and heated up to 1200 ° C by applying a voltage. The heating at 1200 ° C takes place for 2 minutes, then the power supply is interrupted for 15 seconds. At the end of the life of the wire fails by the fact that the remaining cross-section melts through.
  • An analogue endurance test can be performed on foil strips.
  • foil strips of 50 ⁇ m thickness and 6 mm width are clamped between 2 current feedthroughs and heated up to 1050 ° C by applying a voltage.
  • the heating to 1050 ° C was carried out for 15 s, then the power supply is interrupted for 5 s.
  • At the end of the life of the film fails by the fact that the remaining cross-section melts through.
  • the lifetime of both tests is the total time that the wire or film is at the stated temperature without interruption times.
  • the temperature is measured during the life test with an optical pyrometer and, if necessary, corrected to the setpoint temperature.
  • the results of the lifetime tests are listed in Table 1.
  • the mean values given in the table are in each case the mean values of at least 3 samples.
  • the large-scale smelted alloys G1 and G2 and the laboratory smelted alloy L2 show an iron-chromium-aluminum alloy with (in mass%) about 20% Cr, about 5% Al and additions of 0.04 to 0.07% Y, 0.04 to 0.07% Zr and 0.04 to 0.05% Ti, a carbon content of 0.033 to 0.037%, an Si content of 0.15 to 0.34%, a Mn content of approx 0.24% and minor contents of N, S, Ce, La, Pr, Ne, P, Mg, Ca as shown in Table 1 in the prior art.
  • the lifetime of L2 on 0.4 mm thick wire at 1200 ° C with a cycle of 120 s "on” and 15 s "off” serves as a reference and is set to 100%.
  • the lifetime of 50 ⁇ m thick film at 1050 ° C and a cycle of 15 s "on” and 5 s “off” is between 102 and 124% of the lifetime of the laboratory batch L1.
  • the large scale molten alloy G3 shows an iron-chromium-aluminum alloy with about 20% Cr, about 5% Al and additions of 0.06% Y, 0.04% Zr, 0.02% Hf, a carbon content of 0.029%, an Si content of 0.28%, a Mn content of 0.20%, and minute contents of P, Mg, Ca as shown in Table 1 in the prior art.
  • the life of 50 ⁇ m thick film at 1050 ° C and a cycle of 15 s "on” and 5 s “off” is 148% of the lifetime of the laboratory batch L1.
  • the prior art alloys have the life test on 50 ⁇ m thick film at 1050 ° C and a cycle of 15 s "on” and 5 s “off” values of about 100% to about 150% of L1.
  • the variants L3 and L7 with only one Y Addition of 0.06% or 0.05% and a carbon content of 0.002 or 0.031% and a Si content of 0.34 or 0.35% has in the test on wire a life of only 41% or 51%.
  • the variants L4 and L5 with an addition of 0.04 and 0.05% Y and 0.05 and 0.014% Zr and carbon contents of 0.002 and 0.003% and the Si contents of 0.33 and 0.35, respectively % have a lifetime of 79% and 86%, respectively, better than those of L3 and L7, but have not yet reached the lifetimes of L2 or L1.
  • the variant L6 with an addition of 0.05% Y and 0.05% Hf and carbon contents of 0.010% and a Si content of 0.36% has a lifetime of 85%, although also better than that of L3 and L7 but has not reached the lifetime of L2 or L1.
  • the laboratory batch L8 has additions of 0.05% Y, 0.21% Zr and 0.11% Ti and a carbon content of 0.018% and an Si content of only 0.02%. This is due to the high content of Zr and Ti according to J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 even in the concentration range of the increased oxidation rate in the life test with long cycles of z. B. 100 h or 96 h in the oven. Nevertheless, it shows a lifetime of 105% wire life test on wire, which is between L1 and L2.
  • alloys E1, E2 and L8 according to the invention with values between 5 and 7 mm are in the tip group in comparison to the other alloys L1 to L7 after State of the art with values between 17 and 19 mm.
  • the alloys according to the invention thus still have the advantage of high dimensional stability.
  • a minimum content of 0.02% Y is necessary to obtain the oxidation resistance-enhancing effect of Y.
  • the upper limit is set at 0.2% by weight for cost reasons.
  • a minimum content of 0.1% Zr is required in order to reach the high-life range during short and fast temperature cycles.
  • the upper limit is set for cost reasons at 0.3 mass% Zr.
  • a minimum content of 0.02% Hf is necessary to obtain the oxidation resistance enhancing effect of Hf.
  • the upper limit is set for cost reasons at 0.2 mass% Hf.
  • a minimum content of 0.02% Ti is necessary to obtain the oxidation resistance-enhancing effect of Ti.
  • the upper limit is set for cost reasons at 0.2% by mass of Ti.
  • the carbon content should be 0.003% to 0.05% to ensure processability.
  • the nitrogen content should not exceed 0.04% in order to avoid the formation of processability deteriorating nitrides.
  • the levels of phosphorus and sulfur should be kept as low as possible, as these surfactants impair oxidation resistance. It will therefore max. 0.04% P and max. 0.01% S set.
  • Chromium contents between 16 and 24% by mass have no decisive influence on the service life as in J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 to read.
  • a certain chromium content is necessary because chromium promotes the formation of the particularly stable and protective ⁇ - Al 2 O 3 layer. From approx. 16% this is guaranteed. Therefore, the lower limit is 16%.
  • Chromium contents> 24% complicate the processability of the alloy.
  • the aluminum content of the alloy according to the invention should be 4 to 8%. Approximately 4% aluminum are after the " Handbuch der Hochtemperatur-Werkstofftechnik, Ralf Bürgel, Vieweg Verlag, Braunschweig 1998 "on page 272 in Figure 5.13 is required to form a closed ⁇ - Al 2 O 3 layer. Higher Al contents than 8% impair processability.
  • Manganese is limited to 0.5% by weight, as this element reduces the oxidation resistance. The same applies to copper.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Heat Treatment Of Steel (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Resistance Heating (AREA)
  • Soft Magnetic Materials (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Materials For Medical Uses (AREA)
  • Cookers (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)
  • Laminated Bodies (AREA)

Abstract

An iron chromium aluminum alloy having a long service life and comprising (in % by mass) 4 to 8% Al and 16 to 24% Cr and additions of 0.05 to 1% Si, 0.001 to 0.5% Mn, 0.02 to 0.2% Y, 0.1 to 0.3% Zr and/or 0.02 to 0.2% Hf, 0.003 to 0.05% C, 0.0002 to 0.05% Mg, 0.0002 to 0.05% Ca, max. 0.04% N, max. 0.04% P, max. 0.01% S, max. 0.5% Cu and the usual impurities resulting from the melting process, the rest being iron.

Description

Die Erfindung betrifft eine schmelzmetallurgisch hergestellte Eisen-Chrom-Aluminium-Legierung mit hoher Lebensdauer.The invention relates to a melt-metallurgically produced iron-chromium-aluminum alloy with a long service life.

Derartige Legierungen werden zur Herstellung von elektrischen Heizelementen und Katalysatorträgern verwendet. Diese Werkstoffe bilden eine dichte, festhaftende Aluminiumoxidschicht, die sie vor Zerstörung bei hohen Temperaturen (z. B. bis zu 1400°C) schützt. Dieser Schutz wird verbessert durch Zugaben von sogenannten reaktiven Elementen wie beispielsweise Ca, Ce, La, Y, Zr, Hf, Ti, Nb, W, die u.a. die Haftfähigkeit der Oxidschicht verbessern und/oder das Schichtwachstum verringern, wie es zum Beispiel in " Ralf Bürgel, Handbuch der Hochtemperatur-Werkstofftechnik, Vieweg Verlag, Braunschweig 1998 " ab Seite 274 beschrieben wird.Such alloys are used to make electrical heating elements and catalyst supports. These materials form a dense, adherent alumina layer that protects them from destruction at high temperatures (eg up to 1400 ° C). This protection is improved by additions of so-called reactive elements such as Ca, Ce, La, Y, Zr, Hf, Ti, Nb, W, which inter alia improve the adhesion of the oxide layer and / or reduce the layer growth, as for example in " Ralf Bürgel, Handbook of High Temperature Materials Technology, Vieweg Verlag, Braunschweig 1998 "from page 274 is described.

Die Aluminiumoxidschicht schützt den metallischen Werkstoff vor schneller Oxidation. Dabei wächst sie selbst, wenn auch sehr langsam. Dieses Wachstum findet unter Verbrauch des Aluminiumgehaltes des Werkstoffes statt. Ist kein Aluminium mehr vorhanden, so wachsen andere Oxide (Chrom- und Eisenoxide), der Metallgehalt des Werkstoffes wird sehr schnell verbraucht und der Werkstoff versagt durch zerstörende Korrosion. Die Zeit bis zum Versagen wird als Lebensdauer definiert. Eine Erhöhung des Aluminiumgehaltes verlängert die Lebensdauer.The aluminum oxide layer protects the metallic material against rapid oxidation. At the same time she is growing herself, albeit very slowly. This growth takes place using consumption of the aluminum content of the material. If no aluminum is present, other oxides (chromium and iron oxides) grow, the metal content of the material is consumed very quickly and the material fails due to destructive corrosion. The time to failure is defined as the lifetime. An increase in the aluminum content prolongs the service life.

Durch die WO 02/20197 ist eine ferritische nicht rostende Stahllegierung, insbesondere zum Einsatz als Heizleiterelement, bekannt geworden. Die Legierung wird gebildet durch eine pulvermetallurgisch hergestellte FeCrAl-Legierung, beinhaltend (in Masse %) weniger als 0,02 % C, ≤ 0,5 % Si, ≤ 0,2 % Mn, 10;0 bis 40,0 % Cr, ≤ 0,6 % Ni, ≤ 0,01 % Cu, 2,0 bis 10,0 % Al, einem oder mehreren Element(en) aus der Gruppe der reaktiven Elemente, wie Sc, Y, La, Ce, Ti, Zr, Hf, V, Nb, Ta, in Gehalten zwischen 0,1 und 1,0 %, Rest Eisen sowie unvermeidbare Verunreinigungen.By the WO 02/20197 is a ferritic stainless steel alloy, especially for use as Heizleiterelement known. The alloy is formed by a powder metallurgy FeCrAl alloy comprising (in% by mass) less than 0.02% C, ≤ 0.5% Si, ≤ 0.2% Mn, 10.0 to 40.0% Cr, ≤ 0.6% Ni, ≤ 0.01% Cu, 2.0 to 10.0% Al, one or more element (s) from the group of reactive elements, such as Sc, Y, La, Ce, Ti, Zr, Hf, V, Nb, Ta, in contents between 0.1 and 1.0%, balance iron and unavoidable impurities.

In der DE-A 199 28 842 wird eine Legierung mit (in Masse %) 16 bis 22 % Cr, 6 bis 10 % Al und Zugaben von 0,02 bis 1,0 % Si, max. 0,5 % Mn, 0,02 bis 0,1 % Hf, 0,02 bis 0,1 % Y, 0,001 bis 0,01 % Mg, max. 0,02 % Ti, max. 0,03 % Zr, max. 0,02 % SE, max. 0,1 % Sr, max. 0,1 % Ca, max. 0,5 % Cu, max. 0,1 % V, max. 0,1 % Ta, max. 0,1 % Nb, max. 0,03 % C, max. 0,01 % N, max. 0,01 % B, Rest Eisen sowie erschmelzungsbedingte Verunreinigungen für die Verwendung als Trägerfolie für Abgaskatalysatoren, als Heizleiter, als Bauteil im Industrieofenbau und in Gasbrennern beschrieben.In the DE-A 199 28 842 is an alloy with (in mass%) 16 to 22% Cr, 6 to 10% Al and additions of 0.02 to 1.0% Si, max. 0.5% Mn, 0.02 to 0.1% Hf, 0.02 to 0.1% Y, 0.001 to 0.01% Mg, max. 0.02% Ti, max. 0.03% Zr, max. 0.02% SE, max. 0.1% Sr, max. 0.1% Ca, max. 0.5% Cu, max. 0.1% V, max. 0.1% Ta, max. 0.1% Nb, max. 0.03% C, max. 0.01% N, max. 0.01% B, the remainder iron and impurities due to melting for use as a carrier film for catalytic converters, as a heating conductor, as a component in industrial furnace construction and in gas burners.

In der EP-B 0 387 670 wird eine Legierung mit (in Masse %) 20 bis 25 % Cr, 5 bis 8 % Al und Zugaben von 0,03 bis 0,08 % Yttrium, 0,004 bis 0,008 % Stickstoff, 0,020 bis 0,040 % Kohlenstoff, sowie zu etwa gleichen Teilen 0,035 bis 0,07 % Ti und 0,035 bis 0,07 % Zirkonium, und max. 0,01 % Phosphor, max. 0,01 % Magnesium, max. 0,5 % Mangan, max. 0,005 % Schwefel, Rest Eisen beschrieben, wobei die Summe der Gehalte an Ti und Zr 1,75 bis 3,5 % mal so groß ist, wie die prozentuale Summe der Gehalte an C und N sowie erschmelzungsbedingte Verunreinigungen. Ti und Zr kann ganz oder teilweise durch Hafnium und/oder Tantal oder Vanadium ersetzt werden.In the EP-B 0 387 670 becomes an alloy with (in mass%) 20 to 25% Cr, 5 to 8% Al and additions of 0.03 to 0.08% yttrium, 0.004 to 0.008% nitrogen, 0.020 to 0.040% carbon, and approximately equal parts 0.035 to 0.07% Ti and 0.035 to 0.07% zirconium, and max. 0.01% phosphorus, max. 0.01% magnesium, max. 0.5% manganese, max. 0.005% sulfur, remainder iron, wherein the sum of the contents of Ti and Zr is 1.75 to 3.5% times as large as the percentage sum of the contents of C and N as well as impurities caused by melting. Ti and Zr can be completely or partially replaced by hafnium and / or tantalum or vanadium.

In der EP-B 0 290 719 wird eine Legierung mit (in Masse %) 12 bis 30 % Cr, 3,5 bis 8 % Al, 0,008 bis 0,10 % Kohlenstoff, max. 0,8 % Silizium, 0,10 bis 0,4 % Mangan, max. 0,035 % Phosphor, max. 0,020 % Schwefel, 0,1 bis 1,0 % Molybdän, max. 1 % Nickel, und den Zusätzen 0,010 bis 1,0 % Zirkonium, 0,003 bis 0,3 % Titan und 0,003 bis 0,3 % Stickstoff, Kalzium plus Magnesium 0,005 bis 0,05 %, sowie seltene Erdmetalle von 0,003 bis 0,80 %, Niob von 0,5 %, Rest Eisen mit üblichen Begleitelementen beschrieben, die zum Beispiel als Draht für Heizelemente für elektrisch beheizte Öfen und als Konstruktionswerkstoff für thermisch belastete Teile sowie als Folie zur Herstellung von Katalysatorträgern verwendet wird.In the EP-B 0 290 719 is an alloy with (in mass%) 12 to 30% Cr, 3.5 to 8% Al, 0.008 to 0.10% carbon, max. 0.8% silicon, 0.10 to 0.4% manganese, max. 0.035% phosphorus, max. 0.020% sulfur, 0.1 to 1.0% molybdenum, max. 1% nickel, and the additives 0.010 to 1.0% zirconium, 0.003 to 0.3% titanium and 0.003 to 0.3% nitrogen, calcium plus magnesium 0.005 to 0.05%, and rare earth metals from 0.003 to 0.80 %, Niobium of 0.5%, remaining iron described with conventional accompanying elements, for example, as a wire for heating elements for electrically heated furnaces and as a construction material for thermally stressed parts and is used as a film for the preparation of catalyst supports.

In der US 4,277,374 wird eine Legierung mit (in Masse %) bis zu 26 % Chrom, 1 bis 8 % Aluminium, 0,02 bis 2 % Hafnium, bis zu 0,3 % Yttrium, bis zu 0,1 % Kohlenstoff, bis zu 2 % Silizium, Rest Eisen, mit einem bevorzugten Bereich von 12 bis 22 % Chrom und 3 bis 6 % Aluminium beschrieben, die als Folie zur Herstellung von Katalysatorträgern Verwendung findet.In the US 4,277,374 is an alloy with (in mass%) up to 26% chromium, 1 to 8% aluminum, 0.02 to 2% hafnium, up to 0.3% yttrium, up to 0.1% carbon, up to 2% silicon , Rest of iron, with a preferred range of 12 to 22% chromium and 3 to 6% of aluminum, which is used as a film for the preparation of catalyst supports.

Durch die US-A 4,414,023 ist ein Stahl mit (in Masse-%) 8,0 bis 25,0 % Cr, 3,0 bis 8,0 % Al, 0,002 bis 0,06 % Seltenerdmetallen, max. 4,0 % Si, 0,06 bis 1,0 % Mn, 0,035 bis 0,07 % Ti, 0,035 bis 0,07 % Zr einschließlich unvermeidbarer Verunreinigungen bekannt geworden.By the US-A 4,414,023 is a steel with (in mass%) 8.0 to 25.0% Cr, 3.0 to 8.0% Al, 0.002 to 0.06% rare earth metals, max. 4.0% Si, 0.06 to 1.0% Mn, 0.035 to 0.07% Ti, 0.035 to 0.07% Zr, including unavoidable impurities.

Ein detailliertes Modell der Lebensdauer von Eisen-Chrom-Aluminium-Legierungen wird in dem Artikel von I. Gurrappa, S. Weinbruch, D. Naumenko, W. J. Quadakkers, Materials and Corrosions 51 (2000), Seiten 224 bis 235 beschrieben. Dort wird ein Model dargelegt, dass die Lebensdauer von Eisen-Chrom-Aluminium-Legierungen in Abhängigkeit vom Aluminiumgehalt und der Probenform abhängig ist, wobei in dieser Formel mögliche Abplatzungen noch nicht berücksichtigt werden t B = 4 , 4 × 10 - 3 × C 0 - C B × ρ • f k 1 n mit f = 2 × Volumen Oberfläche

Figure imgb0001

  • tB = Lebensdauer, definiert als Zeit bis zum Auftreten anderer Oxide als Aluminiumoxid
  • C0 = Aluminium-Konzentration am Beginn der Oxidation
  • CB = Aluminium-Konzentration bei Auftreten von anderen Oxiden als Aluminiumoxiden
  • ρ = spezifische Dichte der metallischen Legierung
  • k = Oxidationsgeschwindigkeitskonstante
  • n = Oxidationsgeschwindigkeitsexponent
A detailed model of the life of iron-chromium-aluminum alloys is given in the article by I. Gurrappa, S. Weinbruch, D. Naumenko, WJ Quadakkers, Materials and Corrosion 51 (2000), pages 224 to 235 described. There, a model is presented that the lifetime of iron-chromium-aluminum alloys depending on the aluminum content and the sample shape is dependent, in this formula, possible flakes are not taken into account t B = 4 . 4 × 10 - 3 × C 0 - C B × ρ • f k 1 n With f = 2 × volume surface
Figure imgb0001
  • t B = lifetime, defined as the time until oxides other than alumina appear
  • C 0 = aluminum concentration at the beginning of the oxidation
  • C B = aluminum concentration in the presence of oxides other than aluminum oxides
  • ρ = specific gravity of the metallic alloy
  • k = oxidation rate constant
  • n = oxidation rate exponent

Mit Berücksichtigung der Abplatzungen ergibt sich für eine flache Probe unendlicher Breite und Länge mit der Dicke d (f ≈ d) die folgende Formel: t B = 4 , 4 × 10 - 3 × C 0 - C B × ρ × d × k - 1 n × Δ ⁢ m * 1 n - 1

Figure imgb0002

wobei Δm* die kritische Gewichtsänderung ist, bei der die Abplatzungen beginnen.Taking into account the flaking results for a flat sample of infinite width and length with the thickness d (f ≈ d), the following formula: t B = 4 . 4 × 10 - 3 × C 0 - C B × ρ × d × k - 1 n × Δ ⁢ m * 1 n - 1
Figure imgb0002
where Δm * is the critical weight change at which the flakes begin.

Beide Formeln drücken aus, dass die Lebensdauer mit Verringerung des Aluminium-Gehaltes und einem großen Oberflächen zu Volumen Verhältnis (oder kleiner Probendicke) sinkt. Nicht berücksichtigt wurde in diesem Artikel der Einfluss des Temperaturzyklus, wie er z. B in: J.P. Wilber, M.J. Bennett and J.R. Nicholls, "The effect of thermal cycling on the mechanical failure of alumina scales formed on commercial FeCrAl-RE alloys, in Proc. of Int. Conf. on Cyclic Oxidation of High Temperature Materials", Feb. 1999, Frankfurt am Main, Germany, Editors M. Schütze and W.J. Quadakkers, p. 133 - 147 (1999 ) für Zykluszeiten von 1h bis 290 h beschrieben wird, wobei bei dieser Arbeit die Zykluszeiten nur dann einen Einfluss haben, wenn Abplatzungen auftreten.Both formulas express that the lifetime decreases with reduction of the aluminum content and a large surface to volume ratio (or small sample thickness). This article did not take into account the influence of the temperature cycle, as it is eg. B in: JP Wilber, MJ Bennett and JR Nicholls, "The effect of thermal cycling on the mechanical failure of alumina scales formed on commercial FeCrAl-RE alloys, in Proc. Of Int. Conf. On Cyclic Oxidation of High Temperature Materials", Feb. 1999 , Frankfurt am Main, Germany, Editors M. Sagittarius and WJ Quadakkers, p. 133-147 (1999 ) is described for cycle times of 1 h to 290 h, in which case the cycle times have an influence only if flaking occurs.

Auch in V.K. Tolpygo, D.R. Clarke, "Spalling failure of α-alumina films grown by oxidation: I. Dependence on cooling rate and metal thickness, Materials science and engineering", A278 p. 142 - 150 (2000 ) wird der Einfluss der Zykluszeit und der Abkühlgeschwindigkeit beschrieben. Insbesondere zeigen diese beiden Artikel, dass eine kurze Aufheizzeit, eine kurze Abkühlzeit und eine nur kurze Haltezeit bei der hohen Temperatur die Lebensdauer stark verkürzen.Also in VK Tolpygo, DR Clarke, "Spalling failure of α-alumina films grown by oxidation: I. Dependence on cooling rate and metal thickness, Materials science and engineering", A278 p. 142 - 150 (2000 ) describes the influence of the cycle time and the cooling rate. In particular, these two articles show that a short heat-up time, a short cool-down time, and a short hold time at the high temperature greatly shorten the life.

Mit Temperaturzyklus ist im Folgenden die Kombination von Aufheizzeit, Haltezeit bei Temperatur, Abkühlzeit und Wartezeit bis zum erneuten Aufheizen definiert. Temperaturzyklen mit einer kurzen Aufheizzeit, einer kurzen Abkühlzeit und einer nur kurzen Haltezeit bei der hohen Temperatur werden im Folgenden kurze und schnelle Temperaturzyklen genannt. Dazu zählen z. B. Temperaturzyklen mit einer Gesamtdauer im Bereich von mehreren Sekunden bis mehreren Minuten, wobei mit Gesamtdauer die Summe von Aufheizzeit, Haltezeit bei Temperatur, Abkühlzeit und Wartezeit bis zum Beginn der nächsten Aufheizung gemeint ist.With temperature cycle, the combination of heating time, holding time for temperature, cooling time and waiting time until reheating is defined below. Temperature cycles with a short heat-up time, a short cooling time and a Only short hold time at the high temperature are called short and fast temperature cycles in the following. These include z. B. Temperature cycles with a total duration in the range of several seconds to several minutes, where total duration is the sum of heating time, holding time at temperature, cooling time and waiting time until the beginning of the next heating is meant.

Heizleiter, die aus dünnen Folien (z. B. ca. 30 bis 100 µm Dicke bei einer Breite im Bereich von einem oder mehreren Millimetern) bestehen, zeichnen sich durch ein großes Oberflächen zu Volumenverhältnis aus. Dies ist vorteilhaft, wenn man schnelle Aufheiz- und Abkühlzeiten erreichen möchte, wie sie z. B. bei den in Ceranfeldern verwendeten Heizleitern gefordert werden, um das Aufheizen schnell sichtbar werden zu lassen und ein schnelles Erwärmen ähnlich einem Gaskocher zu erreichen. Gleichzeitig ist aber das große Oberflächen- zu Volumenverhältnis nachteilig für die Lebensdauer des Heizleiters (siehe oben). Zusätzlich muss in dieser Anwendung die Temperatur unter dem Glas begrenzt werden, um es vor Schaden zu schützen. Dies kann durch wiederholtes, kurzzeitiges Abschalten des Stromes erreicht werden. Beides hat eine Belastung des Heizleiters durch kurze Aufheizzeiten und schnelle Abkühlung und nur kurze Haltezeiten zur Folge, was, wie oben beschrieben, die Lebensdauer weiter verringert.Heating conductors, which consist of thin foils (for example, about 30 to 100 microns thick with a width in the range of one or more millimeters), are characterized by a large surface area to volume ratio. This is advantageous if you want to achieve fast heating and cooling times, as z. As required in the heating elements used in Ceranfeldern to let the heating quickly become visible and to achieve a rapid heating similar to a gas cooker. At the same time, however, the large surface area to volume ratio is disadvantageous for the service life of the heating conductor (see above). In addition, in this application, the temperature under the glass must be limited to protect it from damage. This can be achieved by repeated, momentary switching off of the current. Both have a burden of the heating by short heating times and rapid cooling and only short hold times result, which, as described above, further reduces the life.

In keiner der vorab erwähnten Druckschriften wird auf diesen Effekt des Temperaturzyklus besonders eingegangen, d. h. keine der oben erwähnten Legierungen ist in dieser Hinsicht entwickelt worden.In none of the above-mentioned references is particularly addressed this effect of the temperature cycle, d. H. none of the alloys mentioned above has been developed in this regard.

Es ist aus dem oben beschriebenen Stand der Technik bekannt, dass geringfügige Zugaben von Y, Zr, Ti, Hf, Ce, La, Nb, W die Lebensdauer von FeCrAl-Legierungen stark beeinflussen.It is known from the prior art described above that minor additions of Y, Zr, Ti, Hf, Ce, La, Nb, W greatly affect the life of FeCrAl alloys.

Nach J. Klöwer, Materials and Corrosion 51 (2000), Seiten 373 bis 385 darf die Zugabe nicht zu groß sein, da sonst eine erhöhte Oxidationsrate auftritt, was einen erhöhten Verbrauch an Aluminium und damit eine verkürzte Lebensdauer bedeutet. Diese erhöhte Oxidationsrate bewirkt z.B. eine Zugabe von nur 0,11 % Hafnium zu einer Eisen-Chrom-Aluminium - Legierung mit 20 % Cr, 7 % Aluminium und 0,01 % Yttrium. Weitere Beispiele für eine erhöhte Oxidationsrate durch eine zu große Zugabe eines reaktiven Elementes in dem erwähnten Artikel sind eine Eisen-Chrom-Aluminium-Legierung mit 18,8 % Cr, 7 % Al und einer Zugabe von 0,11 % Y oder eine Eisen-Chrom-Aluminium-Legierung mit 20 % Cr, 7 % Al und Zugaben von 0,04% Yttrium, 0,05% Zr und 0,05% Ti. Dabei verschiebt sich der Bereich, in dem eine erhöhte Oxidationsrate durch eine zu große Zugabe eines reaktiven Elementes auftritt, mit dem Aluminium-Gehalt. So verursacht nach J. Klöwer, Materials and Corrosion 51 (2000), Seiten 373 bis 385 0,04% Zr in einer Eisen-Chrom-Aluminium- Legierung mit 20% Cr, 7% Al und 0,05 % Y bereits eine erhöhte Oxidationsrate. Die gleiche Menge Zr in einer Eisen-Chrom-Aluminium-Legierung mit 20 % Cr, 5,5 % Al und 0,05 % Y und 0,05 % Hf ( J. Klöwer, A. Kolb-Telieps, M Brede: in Bode, H. (Ed.) Metal-Supported Automotive Catalytic Converters, DGM Informationsgesellschaft, Oberursel, 1997, s.33ff ) verursacht aber keine erhöhte Oxidationsrate. Alle Untersuchungen in J. Klöwer, Materials and Corrosion 51 (2000), Seiten 373 bis 385 und ( J. Klöwer, A. Kolb-Telieps, M Brede: in Bode, H. (Ed.) Metal-Supported Automotive Catalytic Converters, DGM Informationsgesellschaft, Oberursel, 1997, s.33 ff wurden mit Zyklen von 100 h bzw. 96 h im Ofen durchgeführt, was sehr lange Zyklen sind. After J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 The addition should not be too large, as otherwise an increased oxidation rate occurs, which means an increased consumption of aluminum and thus a shortened life. This increased oxidation rate causes, for example, an addition of only 0.11%. Hafnium to an iron-chromium-aluminum alloy with 20% Cr, 7% aluminum and 0.01% yttrium. Further examples of an increased oxidation rate due to an excessively high addition of a reactive element in the mentioned article are an iron-chromium-aluminum alloy with 18.8% Cr, 7% Al and an addition of 0.11% Y or an iron oxide. Chromium-aluminum alloy with 20% Cr, 7% Al and additions of 0.04% yttrium, 0.05% Zr and 0.05% Ti. It shifts the range in which an increased rate of oxidation by adding too much a reactive element occurs with the aluminum content. So caused after J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 0.04% Zr in an iron-chromium-aluminum alloy with 20% Cr, 7% Al and 0.05% Y already has an increased oxidation rate. The same amount of Zr in an iron-chromium-aluminum alloy containing 20% Cr, 5.5% Al and 0.05% Y and 0.05% Hf ( J. Klöwer, A. Kolb-Telieps, M Brede: in Bode, H. (Ed.) Metal-Supported Automotive Catalytic Converters, DGM Information Society, Oberursel, 1997, p.33ff ) but does not cause an increased oxidation rate. All examinations in J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 and ( J. Klöwer, A. Kolb-Telieps, M Brede: in Bode, H. (Ed.) Metal-Supported Automotive Catalytic Converters, DGM Information Society, Oberursel, 1997, p.33 ff were carried out with cycles of 100 h and 96 h, respectively, which are very long cycles.

Der Erfindung liegt die Aufgabe zugrunde, eine Eisen-Chrom-Aluminium Legierung bereitzustellen, die eine höhere Lebensdauer als die bisher verwendeten Eisen-Chrom-Aluminium-Legierungen, insbesondere für Bauteile mit großem Oberflächen zu Volumenverhältnis, beziehungsweise kleiner Banddicke, hat.The invention has for its object to provide an iron-chromium-aluminum alloy, which has a longer life than the previously used iron-chromium-aluminum alloys, especially for components with high surface area to volume ratio, or smaller band thickness.

Diese Aufgabe wird gelöst durch eine schmelzmetallurgisch hergestellte Eisen-Chrom-Aluminium-Legierung mit hoher Lebensdauer gemäß Anspruch 1.This object is achieved by a melt-metallurgically produced iron-chromium-aluminum alloy with a long service life according to claim 1.

Vorteilhafte Weiterbildungen der erfindungsgemäßen Legierung sind den Unteransprüchen zu entnehmen.Advantageous developments of the alloy according to the invention can be found in the subclaims.

Das Element Hf kann des Weiteren durch mindestens eines der Elemente Sc und/oder Ti und/oder V und/oder Nb und/oder Ta und/oder La und/oder Cer ganz bzw. teilweise ersetzt werden, wobei bei teilweiser Substitution Bereiche zwischen 0,02 und 0,15 Masse % denkbar sind.The element Hf may be further replaced by at least one of the elements Sc and / or Ti and / or V and / or Nb and / or Ta and / or La and / or cerium wholly or partly, wherein at partial substitution ranges between 0 , 02 and 0.15 mass% are conceivable.

Vorteilhafterweise soll die erfindungsgemäße Legierung mit (in Masse %) max. 0,02 % N, max. 0,02 % P sowie max. 0,005 % S erschmolzen werden.Advantageously, the alloy according to the invention with (in% by mass) max. 0.02% N, max. 0.02% P and max. 0.005% S are melted.

Beim Stand der Technik gemäß Corrosion 51 (2000) und DGM Informationsgesellschaft wurden alle Untersuchungen mit Zyklen von 100 h bzw. 96 h im Ofen durchgeführt, was sehr lange Zyklen sind.In the state of the art according to Corrosion 51 (2000) and DGM Informationsgesellschaft, all tests were carried out with cycles of 100 h and 96 h, respectively, which are very long cycles.

Überraschenderweise hat es sich bei Versuchen mit sehr kurzen Zyklen gezeigt, dass der Bereich einer verringerten Lebensdauer, was gleichzeitig eine erhöhte Oxidationsrate bedeutet, dort völlig anders liegt. So zeigt sich für die erfindungsgemäße Eisen-Chrom-Aluminium-Legierung, die mit min 0,1 % Zr bei min. 0,02 % Y, die bei den oben erwähnten Zyklen von 100 h bzw. 96 h im Ofen nach J. Klöwer, Materials and Corrosion 51 (2000), Seiten 373 bis 385 schon eine erhöhte Oxidationsrate zeigen würde und damit eine verkürzte Lebensdauer, bei einem Lebensdauertest an Draht, der ein geringes Oberflächen zu Volumenverhältnis hat, mit dem kürzeren Zyklus von 2 min "an" und 15 s "aus" eine am oberen Ende des Variationsbereiches der Lebensdauer der Legierung nach dem Stand der Technik liegende Lebensdauer. Dieser Unterschied wird noch gravierender, wenn man beim Lebensdauertest zu Folien von 50 µm Dicke, die ein sehr großes Oberflächen zu Volumenverhältnis haben und sehr kurzen Zyklen von 15 s "an" und 5 s "aus" übergeht.Surprisingly, it has been found in experiments with very short cycles, that the area of a reduced life, which also means an increased oxidation rate, is completely different there. Thus, the iron-chromium-aluminum alloy according to the invention, which with at least 0.1% Zr at min. 0.02% Y, in the above-mentioned cycles of 100 h and 96 h in the oven after J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 already show an increased oxidation rate and thus a shortened life, with a wire life test having a low surface to volume ratio, with the shorter cycle of 2 minutes "on" and 15 seconds "off" one at the upper end of the variation range of life The alloy according to the prior art lifetime. This difference becomes even more serious when passing the life test to 50μm thick films that have a very high surface area to volume ratio and very short cycles of 15s "on" and 5s "off".

Bevorzugte Fe-Cr-Al-Legierungen zeichnen sich durch folgende Zusammensetzung (in Masse %) aus: Al 5 - 6% 5 - 6% Cr 18 - 22 % 18 - 22% Si 0,05 - 0,7 % 0,05 - 0,7 % Mn 0,001 - 0,4 % 0,001 - 0,4 % Y 0,03 - 0,1 % 0,03 - 0,1 % Zr 0,15 - 0,25 % Hf 0,02-0,15% 0,02 - 0,15 % C 0,003 - 0,03 % 0,003 - 0,3 % Mg 0,0002 - 0,03 % 0,0002 - 0,03 % Ca 0,0002 - 0,03 % 0,0002 - 0,03 % N max. 0,04 % max. 0,04 % P max. 0,04 % max. 0,04 % S max. 0,01 % max. 0,01 % Cu max. 0,5 % max. 0,5 % Preferred Fe-Cr-Al alloys are characterized by the following composition (in% by mass): al 5 - 6% 5 - 6% Cr 18 - 22% 18 - 22% Si 0.05 - 0.7% 0.05 - 0.7% Mn 0.001 - 0.4% 0.001 - 0.4% Y 0.03 - 0.1% 0.03 - 0.1% Zr 0.15 - 0.25% Hf 0.02-0.15% 0.02 - 0.15% C 0.003 - 0.03% 0.003 - 0.3% mg 0.0002 - 0.03% 0.0002 - 0.03% Ca 0.0002 - 0.03% 0.0002 - 0.03% N Max. 0.04% Max. 0.04% P Max. 0.04% Max. 0.04% S Max. 0.01% Max. 0.01% Cu Max. 0.5% Max. 0.5%

Je nach Einsatzfall können folgende Elemente in ihren Spreizungsbereichen wie folgt eingestellt werden: Hf 0,03 - 0,11 % C 0,003 - 0,025 % Mg 0,0002 - 0,01 % Ca 0,0002 - 0,01 % Depending on the application, the following elements can be set in their spreading ranges as follows: Hf 0.03 - 0.11% C 0.003 - 0.025% mg 0.0002 - 0.01% Ca 0.0002 - 0.01%

Die erfindungsgemäße Legierung ist bevorzugt einsetzbar für elektrische Heizelemente, insbesondere mit kurzen Aufheiz- sowie Abkühlzeiten, kurzen Haltezeiten auf Temperatur und kurzen Wartezeiten bis zu dem Beginn einer neuen Aufheizung.The alloy according to the invention is preferably usable for electrical heating elements, in particular with short heating and cooling times, short holding times to temperature and short waiting times until the beginning of a new heating.

Die erfindungsgemäße Legierung ist auch einsetzbar in Heizelementen, die eine hohe Formstabilität bzw. ein geringes Sagging erfordern.The alloy according to the invention can also be used in heating elements which require high dimensional stability or low sagging.

Ebenfalls einsetzbar ist die erfindungsgemäße Legierung in Heizleitern aus Folien mit einer Dicke von 20 bis 100 µm.The alloy according to the invention can also be used in heating conductors made of films having a thickness of from 20 to 100 μm.

Bevorzugt ist auch der Einsatz als Heizleiterlegierung für den Einsatz in Kochfeldern.Preference is also the use as Heizleiterlegierung for use in hobs.

Schließlich besteht ebenfalls die Möglichkeit die erfindungsgemäße Legierung für den Einsatz im Ofenbau zu verwenden.Finally, it is also possible to use the alloy according to the invention for use in furnace construction.

Weitere bevorzugt einsetzbare Legierungsbereiche sind in den entsprechenden Unteransprüchen angegeben.Further preferably usable alloy ranges are given in the corresponding subclaims.

Die Details und die Vorteile der Erfindung werden in den folgenden Beispielen näher erläutert.The details and advantages of the invention will be more apparent from the following examples.

In Tabelle 1 sind labormäßig erschmolzene Eisen-Chrom Aluminium-Legierungen L1 bis L8 und E1 bis E6 und die großtechnisch erschmolzenen Legierungen G1 bis G3 zusammengestellt. Bei den labormäßig erschmolzenen Legierungen wurde aus dem in Blöcken abgegossenen Material mittels Warm- und Kaltumformung und geeigneten Zwischenglühungen sowohl Draht als auch 50 µm dicke Folie hergestellt. Die Folie wurde in Streifen von 6 mm Breite zerschnitten. Bei den großtechnisch erschmolzenen Legierungen wurde aus der großtechnischen Fertigung ein Muster bei der Banddicke 50 µm entnommen und ggf. auf die passende Breite von ca. 6mm geschnitten.Table 1 summarizes laboratory-molten iron-chromium aluminum alloys L1 to L8 and E1 to E6 and the large-scale molten alloys G1 to G3. In the case of the alloys smelted in the laboratory, both wire and 50 μm thick film were produced from the material cast in blocks by means of hot and cold forming and suitable intermediate annealing. The film was cut into strips of 6 mm width. For large-scale molten alloys, a sample was taken from large-scale production at the strip thickness of 50 μm and, if necessary, cut to the appropriate width of approx. 6 mm.

Für Heizleiter in Form von Draht sind beschleunigte Lebensdauertests zum Vergleich von Werkstoffen untereinander zum Beispiel mit den folgenden Bedingungen möglich und üblich:For heating conductors in the form of wire accelerated life tests for comparing materials with each other, for example, with the following conditions are possible and common:

Der Heizleiter-Lebensdauertest wird an Drähten mit dem Durchmesser 0,40 mm aus denen Drahtwendeln mit 12 Windungen, einem Wendeldurchmesser von 4 mm und einer Wendellänge von 50 mm durchgeführt. Die Drahtwendeln werden zwischen 2 Stromzuführungen eingespannt und durch Anlegen einer Spannung bis auf 1200°C erhitzt. Die Erhitzung auf 1200°C erfolgt jeweils für 2 Minuten, dann wird die Stromzufuhr für 15 Sekunden unterbrochen. Am Ende der Lebensdauer versagt der Draht dadurch, dass der restliche Querschnitt durchschmilzt.The heat conductor life test is carried out on wires with a diameter of 0.40 mm from which wire coils with 12 turns, a coil diameter of 4 mm and a coil length of 50 mm. The wire helices are clamped between 2 power supply lines and heated up to 1200 ° C by applying a voltage. The heating at 1200 ° C takes place for 2 minutes, then the power supply is interrupted for 15 seconds. At the end of the life of the wire fails by the fact that the remaining cross-section melts through.

Ein analoger Lebensdauertest lässt sich an Folienstreifen durchführen. Hier werden Folienstreifen von 50 µm Dicke und 6 mm Breite zwischen 2 Stromdurchführungen eingespannt und durch Anlegen einer Spannung bis auf 1050 °C erhitzt. Die Erhitzung auf 1050 °C erfolgte jeweils für 15 s, dann wird die Stromzufuhr für 5 s unterbrochen. Am Ende der Lebensdauer versagt die Folie dadurch, dass der restliche Querschnitt durchschmilzt.An analogue endurance test can be performed on foil strips. Here foil strips of 50 μm thickness and 6 mm width are clamped between 2 current feedthroughs and heated up to 1050 ° C by applying a voltage. The heating to 1050 ° C was carried out for 15 s, then the power supply is interrupted for 5 s. At the end of the life of the film fails by the fact that the remaining cross-section melts through.

Als Lebensdauer wird bei beiden Tests die Gesamtzeit, die der Draht, bzw. die Folie auf der genannten Temperatur sind, ohne Unterbrechungszeiten angegeben. Die Temperatur wird während des Lebensdauertests mit einem optischen Pyrometer gemessen und ggf. auf die Solltemperatur korrigiert.The lifetime of both tests is the total time that the wire or film is at the stated temperature without interruption times. The temperature is measured during the life test with an optical pyrometer and, if necessary, corrected to the setpoint temperature.

Die Ergebnisse der Lebensdauertests sind in Tabelle 1 eingetragen. Die in der Tabelle angegebenen Mittelwerte sind jeweils die Mittelwerte von mindestens 3 Proben.The results of the lifetime tests are listed in Table 1. The mean values given in the table are in each case the mean values of at least 3 samples.

Beim Lebensdauertest an Draht sind die Wendeln am Anfang horizontal eingespannt. Im Verlauf des Lebensdauertestes sacken sie ab. Je geringer die Absackung (Sagging), desto größer ist die Formstabilität des Materials. Eine große Formstabilität ist eine vorteilhafte technologische Eigenschaft, da dies bedeutet, dass die aus dem Material gefertigten Teile eine geringe Formänderung während des Gebrauchs bei höheren Temperaturen zeigen.In the life test on wire, the coils are clamped horizontally at the beginning. In the course of the life test they sag. The lower the sagging, the greater the dimensional stability of the material. Great dimensional stability is an advantageous technological property because it means that the parts made of the material show little change in shape during use at higher temperatures.

Die großtechnisch erschmolzenen Legierungen G1 und G2 und die labormäßig erschmolzene Legierung L2 zeigen eine Eisen-Chrom-Aluminium-Legierung mit (in Masse %) ca. 20 % Cr, ca. 5 % Al und Zugaben von 0,04 bis 0,07% Y, 0,04 bis 0,07% Zr und 0,04 bis 0,05 %Ti, einem Kohlenstoffgehalt von 0,033 bis 0,037%, einem Si-Gehalt von 0,15 bis 0,34%, einem Mn-Gehalt von ca. 0,24% und geringfügigen Gehalten an N, S, Ce, La, Pr, Ne , P, Mg, Ca, wie in Tabelle 1 angegeben nach dem Stand der Technik. Die Lebensdauer von L2 an 0,4 mm dicken Draht bei 1200°C bei einem Zyklus von 120 s "an" und 15 s "aus" dient als Referenz und wird zu 100 % gesetzt.The large-scale smelted alloys G1 and G2 and the laboratory smelted alloy L2 show an iron-chromium-aluminum alloy with (in mass%) about 20% Cr, about 5% Al and additions of 0.04 to 0.07% Y, 0.04 to 0.07% Zr and 0.04 to 0.05% Ti, a carbon content of 0.033 to 0.037%, an Si content of 0.15 to 0.34%, a Mn content of approx 0.24% and minor contents of N, S, Ce, La, Pr, Ne, P, Mg, Ca as shown in Table 1 in the prior art. The lifetime of L2 on 0.4 mm thick wire at 1200 ° C with a cycle of 120 s "on" and 15 s "off" serves as a reference and is set to 100%.

Die Lebensdauer an 50 µm dicker Folie bei 1050 °C und einem Zyklus von 15 s "an" und 5 s "aus" beträgt zwischen 102 und 124 % der Lebensdauer der Laborcharge L1. Auch die großtechnisch erschmolzene Legierung G3 zeigt eine Eisen-Chrom-Aluminium-Legierung mit ca. 20 % Cr, ca. 5 % Al und Zugaben von 0,06 % Y, 0,04 % Zr, 0,02 % Hf, einem Kohlenstoffgehalt von 0,029 %, einem Si-Gehalt von 0,28 %, einem Mn-Gehalt von 0,20% und geringfügigen Gehalten an P, Mg, Ca, wie in Tabelle 1 angegeben nach dem Stand der Technik. Die Lebensdauer an 50 µm dicker Folie bei 1050 °C und einem Zyklus von 15 s "an" und 5 s "aus" beträgt 148 % der Lebensdauer der Laborcharge L1. Damit haben die Legierungen nach dem Stand der Technik bei dem Lebensdauertest an 50 µm dicker Folie bei 1050 °C und einem Zyklus von 15 s "an" und 5 s "aus" Werte von ca. 100% bis ca. 150% von L1.The lifetime of 50 μm thick film at 1050 ° C and a cycle of 15 s "on" and 5 s "off" is between 102 and 124% of the lifetime of the laboratory batch L1. Also, the large scale molten alloy G3 shows an iron-chromium-aluminum alloy with about 20% Cr, about 5% Al and additions of 0.06% Y, 0.04% Zr, 0.02% Hf, a carbon content of 0.029%, an Si content of 0.28%, a Mn content of 0.20%, and minute contents of P, Mg, Ca as shown in Table 1 in the prior art. The life of 50 μm thick film at 1050 ° C and a cycle of 15 s "on" and 5 s "off" is 148% of the lifetime of the laboratory batch L1. Thus, the prior art alloys have the life test on 50 μm thick film at 1050 ° C and a cycle of 15 s "on" and 5 s "off" values of about 100% to about 150% of L1.

Bei den Laborchargen L1 und L3 bis L8 sind die die Gehalte an Si, C, Zr, Ti und Hf variiert worden. Nicht variiert wurde der Gehalt an Mn, der bei allen Laborschmelzen zwischen 0,24 und 0,28 % liegt und die geringfügigen Beimengungen an P, Mg, Ca, Ce, La, Pr, Ne, wie in Tabelle 1 angegeben. Dabei zeigt beim Lebensdauertest an 0,4 mm dicken Draht bei 1200 °C bei einem Zyklus von 120 s "an" und 15 s "aus" die Variante L1 mit 0,03 % Y, 0,04 % Zr und 0,02% Hf und einem Kohlenstoffgehalt von 0,007% und einem Si-Gehalt von 0,35% eine recht hohe Lebensdauer von 116 %. Die Varianten L3 und L7 mit nur einer Y Zugabe von 0,06 % bzw. 0,05% und einem Kohlenstoffgehalt von 0,002 bzw. 0,031% und einem Si-Gehalt von 0,34 bzw. 0,35 % hat in dem Test an Draht eine Lebensdauer von nur 41 % bzw. 51 %. Die Varianten L4 und L5 mit einer Zugabe von 0,04 bzw. 0,05 % Y und 0,05 bzw. 0,014 % Zr und Kohlenstoffgehalten von 0,002 bzw. 0,003 % und den Si-Gehalten von 0,33 bzw. 0,35 % haben eine Lebensdauer von 79 % bzw. 86 %, die zwar besser als die von L3 und L7 ist, aber noch nicht die Lebensdauern von L2 oder L1 erreicht. Die Variante L6 mit einer Zugabe von 0,05 % Y und 0,05 % Hf und Kohlenstoffgehalten von 0,010 % und einem Si-Gehalte von 0,36 % hat eine Lebensdauer von 85 %, die zwar ebenfalls besser als die von L3 und L7 ist aber noch nicht die Lebensdauer von L2 oder L1 erreicht. Die Laborcharge L8 hat Zugaben von 0,05 % Y, 0,21 % Zr und 0,11% Ti und eine Kohlenstoffgehalt von 0,018 % und einen Si-Gehalt von nur 0,02 %. Diese liegt durch den hohen Gehalt an Zr und Ti gemäß J. Klöwer, Materials and Corrosion 51 (2000), Seiten 373 bis 385 schon im Konzentrationsbereich der erhöhten Oxidationsrate beim Lebensdauertest mit langen Zyklen von z. B. 100 h oder 96 h im Ofen. Trotzdem zeigt sie eine Lebensdauer bei dem Heizleiterlebensdauertest an Draht von 105 %, womit sie zwischen L1 und L2 liegt.For the laboratory lots L1 and L3 to L8, the contents of Si, C, Zr, Ti and Hf have been varied. Not varied was the content of Mn, which is between 0.24 and 0.28% for all laboratory melts, and the minor additions of P, Mg, Ca, Ce, La, Pr, Ne, as shown in Table 1. At a life test of 0.4 mm thick wire at 1200 ° C at a cycle of 120 s "on" and 15 s "off" the variant L1 shows 0.03% Y, 0.04% Zr and 0.02% Hf and a carbon content of 0.007% and a Si content of 0.35% a fairly long life of 116%. The variants L3 and L7 with only one Y Addition of 0.06% or 0.05% and a carbon content of 0.002 or 0.031% and a Si content of 0.34 or 0.35% has in the test on wire a life of only 41% or 51%. The variants L4 and L5 with an addition of 0.04 and 0.05% Y and 0.05 and 0.014% Zr and carbon contents of 0.002 and 0.003% and the Si contents of 0.33 and 0.35, respectively % have a lifetime of 79% and 86%, respectively, better than those of L3 and L7, but have not yet reached the lifetimes of L2 or L1. The variant L6 with an addition of 0.05% Y and 0.05% Hf and carbon contents of 0.010% and a Si content of 0.36% has a lifetime of 85%, although also better than that of L3 and L7 but has not reached the lifetime of L2 or L1. The laboratory batch L8 has additions of 0.05% Y, 0.21% Zr and 0.11% Ti and a carbon content of 0.018% and an Si content of only 0.02%. This is due to the high content of Zr and Ti according to J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 even in the concentration range of the increased oxidation rate in the life test with long cycles of z. B. 100 h or 96 h in the oven. Nevertheless, it shows a lifetime of 105% wire life test on wire, which is between L1 and L2.

Ebenfalls im Bereich der erhöhten Oxidationsrate beim Lebensdauertest mit langen Zyklen von z. B. 100h oder 96 h im Ofen liegen die erfindungsgemäßen Legierungen E1 mit 0,05 % Y, 0,18 % Zr, 0,04 % Hf, 0,006% C und 0,35 % Si und E2 mit 0,03 % Y, 0,20 % Zr, 0,11 % Ti anstelle des Hafniums, 0,020% C und 0,61 % Si. Beide Legierungen haben gute Lebensdauern von 96 % für E2 und sogar 118 % für E1 in dem Heizleiterlebensdauertest an Draht. Damit ergibt sich für die Laborschmelzen das folgende Ranking für die Lebensdauer (sortiert jeweils mit fallender Lebensdauer):

  • Spitzengruppe: E1, L1, L8, L2, E2, gekennzeichnet durch Zugaben von Y und Zr und darüber hinaus eine Zugabe von Ti oder Hf.
  • Mittlere Lebensdauer: L5, L6, L4, gekennzeichnet durch Zugaben von Y und Zr oder Y und Hf.
  • Schlechte Lebensdauer: L7, L3, gekennzeichnet durch eine Zugabe von nur Y.
    Dies entspricht dem Wissen und den Erfahrungen des Standes der Technik. Die Legierung L2 entspricht z. B. den großtechnisch erschmolzenen Legierungen nach dem Stand der Technik G1 und G2.
    Das Bild sieht etwas anders aus, wenn der Heizleiterlebensdauertest an 50 µm dicker Folie bei 1050 °C und einem Zyklus von 15 s "an" und 5 s "aus" betrachtet wird: Die beim Test an Draht eine schlechte Lebensdauer zeigenden Legierungen L3 und L7 zeigen eine Lebensdauer von 94 % und 110 % von L1, was in dem Bereich der Lebensdauer der Legierungen nach dem Stand der Technik liegt. Die beim Test an Draht eine mittlere Lebensdauer zeigenden Legierungen L5, L6, L4 zeigen eine Lebensdauer von 145 % bzw. 113 % von L1, was ebenfalls in dem Bereich der Lebensdauer der Legierungen nach dem Stand der Technik liegt. Die beim Test an Draht in der Spitzengruppe sich befindenden Legierungen L1 und L2 zeigen eine Lebensdauer von 100% bzw. 125% von L1, die Legierung L8 zeigt eine Lebensdauer von guten 140% von L1, was in dem Bereich der Lebensdauer der Legierungen nach dem Stand der Technik liegt.
    Überraschenderweise zeigten die angeführten erfindungsgemäßen Legierungen E1 und E2 im Bereich der erhöhten Oxidationsrate beim Lebensdauertest mit langen Zyklen von z. B. 100 h oder 96 h im Ofen liegenden Legierungen E1 und E2 sehr hohe Lebensdauern von mit 256 % einen alle anderen weit überragenden Wert bei E1 und 171% bei E2, was deutlich über den Bereich der Lebensdauer der Legierungen nach dem Stand der Technik hinausgeht. Ähnlich überraschend hohe Lebensdauern zeigen die erfindungsgemäßen Legierungen E3 mit 201% und Gehalten an 0,05 % Y, 0,21 % Zr, 0,021 % C und 0,19 % Si und E4 mit 227 % und Gehalten an 0,07 % Y, 023 % Zr, 0,07 % Ti, 0,014 % C und 0,19 % Si und E5 mit 249 % und Gehalten an 0,07 % Y, 0,22 % Zr, 0,07 % Hf, 0,018 % C und 0,20 % Si und E6 mit 283 % und Gehalten an 0,05 % Y, 0,17 % Zr, 0,05 % Hf, 0,016 % C und 0,19 % Si.
    Damit ergibt sich das folgende Ranking.
  • Spitzeng_ruppe mit Lebensdauern größer 170 % von L1: E1 bis E6, gekennzeichnet durch Zugabe von Y und Zr und/oder Hf und/oder Ti im Bereich der erhöhten Oxidationsrate beim Lebensdauertest mit langen Zyklen von z. B. 100 h oder 96 h im Ofen und einen Kohlenstoffgehalt im Bereich von 0,003 bis 0,025 % und Si-Gehalten von mehr als 0,05 %.
    Gruppe mit Lebensdauern im Bereich von ca. 100 % bis 150 % von L1, was dem
  • Stand der Technik entspricht: G3, L5, L8, L2, G2, L4, L6, G1, L1, L7, L3, gekennzeichnet durch geringere Zugabe von Y und Zr und/oder Hf und/oder Ti außerhalb des Bereichs der erhöhten Oxidationsrate beim Lebensdauertest mit langen Zyklen von z. B. 100 h oder 96 h im Ofen oder im Falle von L8 durch einen zu geringen Si-Gehalt bei einer Zugabe von Y, Zr und Hf im Bereich der erhöhten Oxidationsrate.
Also in the field of increased oxidation rate in the life test with long cycles of z. B. 100h or 96 h in the furnace alloys of the invention E1 with 0.05% Y, 0.18% Zr, 0.04% Hf, 0.006% C and 0.35% Si and E2 with 0.03% Y, 0.20% Zr, 0.11% Ti instead of hafnium, 0.020% C and 0.61% Si. Both alloys have good lifetimes of 96% for E2 and as much as 118% for E1 in the wire ladder life test. This results in the following ranking for the lifetime of the laboratory melts (sorted in each case with falling lifetime):
  • Top group: E1, L1, L8, L2, E2, characterized by additions of Y and Zr and, in addition, addition of Ti or Hf.
  • Average life: L5, L6, L4, characterized by additions of Y and Zr or Y and Hf.
  • Bad lifespan: L7, L3, characterized by an addition of only Y.
    This corresponds to the knowledge and experience of the prior art. The alloy L2 corresponds to z. B. the industrially molten alloys of the prior art G1 and G2.
    The picture looks somewhat different when considering the heater ladder life test on 50 μm thick film at 1050 ° C and a cycle of 15 s "on" and 5 s "off": The alloys L3 and L7 exhibiting poor service life on test on wire show a lifetime of 94% and 110% of L1, which is in the range of lifetime of the prior art alloys. The average life L5, L6, L4 alloys exhibited a life of 145% and 113% of L1, respectively, which is also in the range of lifetime of the prior art alloys. Alloys L1 and L2 found on wire in the lead group show a lifetime of 100% and 125%, respectively, of L1, alloy L8 has a good life of 140% of L1, which is within the range of lifetime of the alloys after State of the art lies.
    Surprisingly, the stated alloys E1 and E2 according to the invention showed in the range of the increased oxidation rate in the life test with long cycles of, for. For example, alloys E1 and E2 that are 100 and 96 hours in the furnace have very high lifetimes of 256%, a value far exceeding that of E1 and 171% at E2, which is well beyond the life of the prior art alloys , Similar surprisingly long lifetimes are exhibited by the alloys E3 according to the invention with 201% and contents of 0.05% Y, 0.21% Zr, 0.021% C and 0.19% Si and E4 with 227% and contents of 0.07% Y, 023% Zr, 0.07% Ti, 0.014% C, and 0.19% Si and E5 at 249% and contents of 0.07% Y, 0.22% Zr, 0.07% Hf, 0.018% C, and 0 , 20% Si and E6 at 283% and contents of 0.05% Y, 0.17% Zr, 0.05% Hf, 0.016% C and 0.19% Si.
    This results in the following ranking.
  • Peak group with lifetimes greater than 170% of L1 : E1 to E6 characterized by the addition of Y and Zr and / or Hf and / or Ti in the region of increased oxidation rate in the long life cycle life test of e.g. In the oven and having a carbon content in the range of 0.003 to 0.025% and Si contents of more than 0.05%.
    Group with lifetimes in the range of about 100% to 150% of L1, which is the
  • The prior art corresponds to : G3, L5, L8, L2, G2, L4, L6, G1, L1, L7, L3, characterized by a lower addition of Y and Zr and / or Hf and / or Ti outside the range of the increased oxidation rate Lifetime test with long cycles of z. B. 100 h or 96 h in the oven or in the case of L8 by a too low Si content with an addition of Y, Zr and Hf in the region of increased oxidation rate.

Bei der für die Anwendungen wichtigen Formstabilität, gemessen als Sagging der Wendeln bei 50 h Brenndauer in mm, liegen die erfindungsgemäßen Legierungen E1, E2 und L8 mit Werten zwischen 5 und 7 mm in der Spitzengruppe im Vergleich zu den übrigen Legierungen L1 bis L7 nach dem Stand der Technik mit Werten zwischen 17 und 19 mm. Die erfindungsgemäßen Legierungen haben damit noch den Vorteil hoher Formstabilität.In the case of the dimensional stability which is important for the applications, measured as Sagging of the coils at 50 h burning time in mm, alloys E1, E2 and L8 according to the invention with values between 5 and 7 mm are in the tip group in comparison to the other alloys L1 to L7 after State of the art with values between 17 and 19 mm. The alloys according to the invention thus still have the advantage of high dimensional stability.

Die beanspruchten Grenzen für die Erfindung lassen sich daher im Einzelnen wie folgt begründen:The claimed limits for the invention can therefore be explained in detail as follows:

Es ist ein Mindestgehalt von 0,02 % Y notwendig, um die die Oxidationsbeständigkeit steigernde Wirkung des Y zu erhalten. Die Obergrenze wird aus Kostengründen bei 0,2 Masse % gelegt.A minimum content of 0.02% Y is necessary to obtain the oxidation resistance-enhancing effect of Y. The upper limit is set at 0.2% by weight for cost reasons.

Es ist ein Mindestgehalt von 0,1 % Zr notwendig, um bei kurzen und schnellen Temperaturzyklen in den Bereich hoher Lebensdauer zu kommen. Die Obergrenze wird aus Kostengründen bei 0,3 Masse % Zr gelegt.A minimum content of 0.1% Zr is required in order to reach the high-life range during short and fast temperature cycles. The upper limit is set for cost reasons at 0.3 mass% Zr.

Es ist ein Mindestgehalt von 0,02 % Hf notwendig, um die die Oxidationsbeständigkeit steigernde Wirkung des Hf zu erhalten. Die Obergrenze wird aus Kostengründen bei 0,2 Masse % Hf gelegt.A minimum content of 0.02% Hf is necessary to obtain the oxidation resistance enhancing effect of Hf. The upper limit is set for cost reasons at 0.2 mass% Hf.

Es ist ein Mindestgehalt von 0,02 % Ti notwendig, um die die Oxidationsbeständigkeit steigernde Wirkung des Ti zu erhalten. Die Obergrenze wird aus Kostengründen bei 0,2 Masse % Ti gelegt.A minimum content of 0.02% Ti is necessary to obtain the oxidation resistance-enhancing effect of Ti. The upper limit is set for cost reasons at 0.2% by mass of Ti.

Der Kohlenstoffgehalt sollte 0,003% bis 0,05 % betragen, um die Verarbeitbarkeit zu gewährleisten.The carbon content should be 0.003% to 0.05% to ensure processability.

Der Stickstoffgehalt sollte maximal 0,04 % betragen, um die Bildung von die Verarbeitbarkeit verschlechternden Nitriden zu vermeiden.The nitrogen content should not exceed 0.04% in order to avoid the formation of processability deteriorating nitrides.

Die Gehalte an Phosphor und Schwefel sollten so gering wie möglich gehalten werden, da diese grenzflächenaktiven Elemente die Oxidationsbeständigkeit beeinträchtigen. Es werden deshalb max. 0,04 % P und max. 0,01 % S festgelegt.The levels of phosphorus and sulfur should be kept as low as possible, as these surfactants impair oxidation resistance. It will therefore max. 0.04% P and max. 0.01% S set.

Chromgehalte zwischen 16 und 24 Masse % haben keinen entscheidenden Einfluss auf die Lebensdauer wie in J. Klöwer, Materials and Corrosion 51 (2000), Seiten 373 bis 385 nach zu lesen ist. Allerdings ist ein gewisser Chromgehalt nötig, da Chrom die Bildung der besonders stabilen und schützenden α - Al2O3 Schicht fördert. Ab ca. 16 % ist dies gewährleistet. Deshalb liegt die Untergrenze bei 16 %. Chromgehalte > 24 % erschweren die Verarbeitbarkeit der Legierung.Chromium contents between 16 and 24% by mass have no decisive influence on the service life as in J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 to read. However, a certain chromium content is necessary because chromium promotes the formation of the particularly stable and protective α - Al 2 O 3 layer. From approx. 16% this is guaranteed. Therefore, the lower limit is 16%. Chromium contents> 24% complicate the processability of the alloy.

Der Aluminiumgehalt der erfindungsgemäßen Legierung sollte bei 4 bis 8 % liegen. Ca. 4 % Aluminium sind nach dem " Handbuch der Hochtemperatur-Werkstofftechnik, Ralf Bürgel, Vieweg Verlag, Braunschweig 1998" auf Seite 272 in Bild 5.13 erforderlich, um eine geschlossene α - Al2O3- Schicht zu bilden. Höhere Al-Gehalte als 8 % beeinträchtigen die Verarbeitbarkeit.The aluminum content of the alloy according to the invention should be 4 to 8%. Approximately 4% aluminum are after the " Handbuch der Hochtemperatur-Werkstofftechnik, Ralf Bürgel, Vieweg Verlag, Braunschweig 1998 "on page 272 in Figure 5.13 is required to form a closed α - Al 2 O 3 layer. Higher Al contents than 8% impair processability.

Nach J. Klöwer, Materials and Corrosion 51 (2000), Seiten 373 bis 385 erhöhen Zugaben von Silizium die Lebensdauer durch eine Verbesserung der Haftung der Deckschicht. Es ist deshalb ein Gehalt von mindestens 0,05 Masse % Silizium erforderlich. Zu hohe Si-Gehalte erschweren die Verarbeitbarkeit der Legierung. Deshalb liegt die Obergrenze bei 1%. After J. Klöwer, Materials and Corrosion 51 (2000), pages 373-385 Additions of silicon increase the life by improving the adhesion of the overcoat. Therefore, a content of at least 0.05 mass% silicon is required. Too high Si contents make the workability of the alloy difficult. Therefore, the upper limit is 1%.

Mangan wird auf 0,5 Masse % begrenzt, da dieses Element die Oxidationsbeständigkeit reduziert. Das Gleiche gilt für Kupfer.Manganese is limited to 0.5% by weight, as this element reduces the oxidation resistance. The same applies to copper.

Die Gehalte an Magnesium und Kalzium werden im Spreizungsbereich 0,0002 bis 0,05 Masse % eingestellt. Tabelle 1. Alle Angaben in Masse % L1 L2 L3 L4 L5 L6 L7 E1 E2 L8 E3 E4 E5 E6 G1 G2 G3 Fe Rest Rest Rest Rest Rest Rest Rest Rest Rest Rest Rest Rest Rest Rest Rest Rest Rest Cr 20,3 20,8 19,8 19,3 20,2 19,8 20,2 19,6 21,1 21,2 20,4 20,5 20,3 20,8 20,8 20,7 20,3 Al 5,6 4,9 5,7 5,5 5,3 5,3 5,4 5,67 5,3 5,3 5,3 5,2 5,4 5,2 5,1 5,3 5,6 Mn 0,28 0,24 0,26 0,25 0,24 0,25 0,25 0,25 0,25 0,26 0,25 0,24 0,24 0,24 0,26 0,25 0,20 Si 0,35 0,34 0,34 0,33 0,35 0,36 0,35 0,35 0,61 0,02 0,19 0,21 0,20 0,19 0,17 0,15 0,28 C 0,007 0,037 0,002 0,002 0,003 0,010 0,031 0,006 0,020 0,018 0,021 0,014 0,018 0,016 0,033 0,034 0,029 S 0,002 0,002 0,004 0,001 0,005 0,001 0,001 0,002 0,002 <0,001 0,003 0,001 0,002 0,003 0,002 0,002 0,002 N 0,005 0,002 <0,001 0,004 0,0025 0,005 0,005 0,002 0,0065 0,004 0,003 0,007 0,004 0,005 0,006 0,006 0,004 Y 0,03 0,04 0,06 0,04 0,05 0,05 0,05 0,05 0,03 0,05 0,05 0,07 0,07 0,05 0,07 0,07 0,06 Zr 0,04 0,048 < 0,01 0,05 0,014 < 0,01 < 0,01 0,18 0,20 0,21 0,21 0,23 0,22 0,17 0,04 0,07 0,04 Hf 0,02 < 0,01 0,01 < 0,01 < 0,01 0,05 < 0,01 0,04 < 0,01 < 0,01 < 0,01 < 0,01 0,07 0,05 <0,001 <0,001 0,02 Ti - 0,04 - - < 0,01 - - <0,01 0,11 0,11 < 0,01 0,07 < 0,01 < 0,01 0,05 0,05 0,01 Ce, La, Pr, Ne < 0,001 < 0,01 < 0,01 < 0,01 < 0,01 < 0,01 < 0,01 <0,01 <0,01 <0,01 <0,01 - - - P 0,003 0,003 0,003 0,002 0,003 0,003 0.002 0,005 0,006 0,002 <0,002 <0,002 <0,002 <0,002 0,012 0.012 0,013 Mg - 0,004 - - 0,004 - - 0,003 0,003 0,003 0,001 0,001 0,001 0,001 0,01 0,01 0,007 Ca - < 0,001 - - < 0,001 - - 0,001 0,001 0,001 0,0002 0,0002 0,0002 0,0002 0,002 0,0005 0,001 Cu <0,01 <0,01 <0,01 <0,01 <0,01 <0,01 <0,01 <0,01 <0,01 0,07 <0,01 <0,01 <0,01 <0,01 0,02 0,02 0,03 V 0,01 0,01 0,01 0,01 0,01 0,01 0,01 0,01 0,01 <0,01 0,02 0,02 0,02 0,03 0,02 0,04 0,07 0,05 Mo 0,01 <0,01 <0,01 0,01 <0,01 0,01 0,01 0,03 0,03 0,01 0,02 0,03 0,02 0,01 <0,01 <0,01 Lebensdauer ± s in % von L2, Draht 0,4 mm, gewendelt 1200°C, 120 s "an"/15 s "aus" 116 ±7 100 ±6 41 ±14 79 ±10 86 ±12 85 ±13 51 ±12 118 ±7 96 ±9 105 ±10 Sagging der Wendeln bei 50h in mm 17 18 15 17 21 19 5 7 6 Lebensdauer ± s in % von L1, Folie 50µm x 6mm, 1050°C, 15 s "an"/ 5 s "aus" 100 ±14 125 ±40 94 ±16 113 ±22 145 ±17 113 ±22 110 ±18 256 ±15 171 ±14 140 ±6 201 ±10 227 ±46 249 ±18 283 ±13 102 ±19 124 ±27 148 ±13 The contents of magnesium and calcium are set in the spread range 0.0002 to 0.05 mass%. Table 1. All figures in mass% L1 L2 L3 L4 L5 L6 L7 E1 E2 L8 E3 E4 E5 E6 G1 G2 G3 Fe rest rest rest rest rest rest rest rest rest rest rest rest rest rest rest rest rest Cr 20.3 20.8 19.8 19.3 20.2 19.8 20.2 19.6 21.1 21.2 20.4 20.5 20.3 20.8 20.8 20.7 20.3 al 5.6 4.9 5.7 5.5 5.3 5.3 5.4 5.67 5.3 5.3 5.3 5.2 5.4 5.2 5.1 5.3 5.6 Mn 0.28 0.24 0.26 0.25 0.24 0.25 0.25 0.25 0.25 0.26 0.25 0.24 0.24 0.24 0.26 0.25 0.20 Si 0.35 0.34 0.34 0.33 0.35 0.36 0.35 0.35 0.61 0.02 0.19 0.21 0.20 0.19 0.17 0.15 0.28 C 0,007 0.037 0,002 0,002 0,003 0,010 0.031 0,006 0,020 0,018 0,021 0,014 0,018 0.016 0.033 0.034 0,029 S 0,002 0,002 0,004 0.001 0.005 0.001 0.001 0,002 0,002 <0.001 0,003 0.001 0,002 0,003 0,002 0,002 0,002 N 0.005 0,002 <0.001 0,004 0.0025 0.005 0.005 0,002 0.0065 0,004 0,003 0,007 0,004 0.005 0,006 0,006 0,004 Y 0.03 0.04 0.06 0.04 0.05 0.05 0.05 0.05 0.03 0.05 0.05 0.07 0.07 0.05 0.07 0.07 0.06 Zr 0.04 0.048 <0.01 0.05 0,014 <0.01 <0.01 0.18 0.20 0.21 0.21 0.23 0.22 0.17 0.04 0.07 0.04 Hf 0.02 <0.01 0.01 <0.01 <0.01 0.05 <0.01 0.04 <0.01 <0.01 <0.01 <0.01 0.07 0.05 <0.001 <0.001 0.02 Ti - 0.04 - - <0.01 - - <0.01 0.11 0.11 <0.01 0.07 <0.01 <0.01 0.05 0.05 0.01 Ce, La, Pr, Ne <0.001 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 - - - P 0,003 0,003 0,003 0,002 0,003 0,003 0002 0.005 0,006 0,002 <0.002 <0.002 <0.002 <0.002 0,012 0012 0,013 mg - 0,004 - - 0,004 - - 0,003 0,003 0,003 0.001 0.001 0.001 0.001 0.01 0.01 0,007 Ca - <0.001 - - <0.001 - - 0.001 0.001 0.001 0.0002 0.0002 0.0002 0.0002 0,002 0.0005 0.001 Cu <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 <0.01 0.07 <0.01 <0.01 <0.01 <0.01 0.02 0.02 0.03 V 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 <0.01 0.02 0.02 0.02 0.03 0.02 0.04 0.07 0.05 Not a word 0.01 <0.01 <0.01 0.01 <0.01 0.01 0.01 0.03 0.03 0.01 0.02 0.03 0.02 0.01 <0.01 <0.01 Life ± s in% of L2, wire 0.4 mm, coiled 1200 ° C, 120 s "on" / 15 s "off" 116 ± 7 100 ± 6 41 ± 14 79 ± 10 86 ± 12 85 ± 13 51 ± 12 118 ± 7 96 ± 9 105 ± 10 Sagging of the coils at 50h in mm 17 18 15 17 21 19 5 7 6 Lifetime ± s in% of L1, foil 50μm x 6mm, 1050 ° C, 15 s "on" / 5 s "off" 100 ± 14 125 ± 40 94 ± 16 113 ± 22 145 ± 17 113 ± 22 110 ± 18 256 ± 15 171 ± 14 140 ± 6 201 ± 10 227 ± 46 249 ± 18 283 ± 13 102 ± 19 124 ± 27 148 ± 13

Claims (18)

  1. An iron chromium aluminium alloy having a long service life and comprising (in % by mass) 4 to 8% aluminium and 16 to 24% chromium and additions of 0.05 to 1% Si, 0.001 to 0.5% Mn, 0.02 to 0.2% Y and 0.1 to 0.3% Zr or 0.1 to 0.3% Zr and 0.02 to 0.2% Hf, 0.003 to 0.05% C, 0.002 to 0.05% Mg, 0.0002 to 0.05% Ca, max. 0.04% N, max. 0.04% P, max. 0.01% S, max. 0.5% Cu and the usual impurities resulting from the melting process, the rest being iron, wherein Hf can be replaced by one or more of the elements Sc, Ti, V, Nb, Ta, La or Ce.
  2. An iron chromium aluminium alloy according to claim 1 comprising (in % by mass) 5 to 6% Al, 18 to 22% Cr and additions of 0.05 to 0.7% Si, 0.001 to 0.4% Mn, 0.03 to 0.1 % Y and 0.15 to 0.25% Zr or 0.15 to 0.25% Zr and 0.02 to 0.15% Hf, 0.003 to 0.03% C, 0.0002 to 0.03% Mg; 0.0002 to 0.03% Ca, max. 0.04% N, max. 0.04% P, max. 0.01% S, max. 0.5% Cu and the usual impurities resulting from the melting process, the rest being iron.
  3. An iron chromium aluminium alloy according to claim 1 or 2 comprising (in % by mass) 5 to 6% Al, 18 to 22% Cr and additions of 0.05 to 0.7% Si, 0.001 to. 0.4% Mn, 0.03 to 0.08% Y and 0.15 to 0.25% Zr or 0.15 to 0.25% Zr and 0.03 to 0.11 % Hf, 0.003 to 0.025% C, 0.0002 to 0.01% Mg, 0.0002 to 0.01% Ca, max. 0.04% N, max. 0.04% P, max. 0.01% S, max. 0.5% Cu and the usual impurities resulting from the melting process, the rest being iron.
  4. An iron chromium aluminium alloy according to one of the claims 1 through 3 comprising (in % by mass) 5 to 6% Al, 18 to 22% Cr and additions of 0.05 to 0.7% Si, 0.001 to 0.4% Mn, 0.03 to 0.08% Y and 0.15 to 0.25% Zr or 0.15 to 0.25% Zr and 0.03 to 0.08% Hf, 0.003 to 0.025% C, 0.002 to 0.01% Mg, 0.0002 to 0.01% Ca, max. 0.04% N, max. 0.04% P, max. 0.01% S, max. 0.5% Cu and the usual impurities resulting from the melting process, the rest being iron.
  5. An iron chromium aluminium alloy according to one of the claims 1 through 4, wherein Hf is partly replaced by (in % by mass) 0.01 to 0.18% of at least one of the elements Sc and/or Ti and/or V and/or Nb and/or Ta and/or La and/or cerium.
  6. An iron chromium aluminium alloy according to one of the claims 1 through 5, wherein Hf is partly replaced by (in % by mass) 0.02 to 0.1 %% of at least one of the elements sc and/or Ti and/or V and/or Nb and/or Ta and/or La and/or cerium.
  7. An iron chromium aluminium alloy according to one of the claims 5 or 6, wherein Hf is completely or partly replaced by (in % by mass) 0.02 to 0.11 % of at least one of the elements Sc and/or Ti and/or V and/or Nb and/or Ta and/or La and/or cerium.
  8. An iron chromium aluminium alloy according to one of the claims 5 through 7, wherein Hf is completely or partly replaced by (in % by mass) 0.03 to 0.07% of at least one of the elements Sc and/or Ti and/or V and/or Nb and/or Ta and/or La and/or cerium
  9. An iron chromium aluminium alloy according to one of the claims 1 through 8 comprising (in % by mass) max. 0.02% N, max. 0.02% P and max. 0.005% S.
  10. An iron chromium aluminium alloy according to one of the claims 1 through 9 comprising (in % by mass) max. 0.01% N, max. 0.02% P and max. 0.003% S.
  11. An iron chromium aluminium alloy according to one of the claims 1 through 10 furthermore comprising (in % by mass) max. 0.1 % Mo and/or 0.1 % W.
  12. A use of the iron chromium aluminium alloy according to one of the claims 1 through 11 as alloy to be used for electric heating elements.
  13. A use of the iron chromium aluminium alloy according to one of the claims 1 through 11 as alloy to be used for electric heating elements having short heating up and cooling down periods, short holding times at the temperature and short waiting times until a new heating up period starts.
  14. A use of the iron chromium aluminium alloy according to one of the claims 1 through 11 as alloy to be used for electric heating elements that require a high dimensional stability or low sagging.
  15. A use of the iron chromium aluminium alloy according to one of the claims 1 through 11 as alloy to be used for heat conductors made of films having a thickness comprised between 20 and 100 µm.
  16. A use of the iron chromium aluminium alloy according to one of the claims 1 through 11 as alloy to be used for heat conductors made of wires having a diameter of < 6 mm.
  17. A use of the iron chromium aluminium alloy according to one of the claims 1 through 11 as heat conductor alloy to be used for cooking zones, in particular glass-ceramic cooking zones.
  18. A use of the iron chromium aluminium alloy according to one of the claims 1 through 11 as heat conductor alloy to be used in the construction of furnaces.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2933349A1 (en) * 2012-12-17 2015-10-21 JFE Steel Corporation Stainless steel sheet and stainless steel foil

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2292232C2 (en) * 2004-10-25 2007-01-27 Общество с ограниченной ответственностью "Объединенный центр исследований и разработок" (ООО "ЮРД-Центр") Reactor for gas separation and/or carrying out chemical reactions and method for manufacturing the same
DE102007005154B4 (en) * 2007-01-29 2009-04-09 Thyssenkrupp Vdm Gmbh Use of an iron-chromium-aluminum alloy with a long service life and small changes in the heat resistance
CN101280392B (en) * 2007-04-04 2011-03-16 泰州市春海电热合金制造有限公司 Anti-carburization high temperature-resistant electrothermal alloy
US8039117B2 (en) * 2007-09-14 2011-10-18 Siemens Energy, Inc. Combustion turbine component having rare earth NiCoCrAl coating and associated methods
US8043718B2 (en) * 2007-09-14 2011-10-25 Siemens Energy, Inc. Combustion turbine component having rare earth NiCrAl coating and associated methods
US7867626B2 (en) * 2007-09-14 2011-01-11 Siemens Energy, Inc. Combustion turbine component having rare earth FeCrAI coating and associated methods
US8043717B2 (en) * 2007-09-14 2011-10-25 Siemens Energy, Inc. Combustion turbine component having rare earth CoNiCrAl coating and associated methods
DE102008018135B4 (en) 2008-04-10 2011-05-19 Thyssenkrupp Vdm Gmbh Iron-chromium-aluminum alloy with high durability and small changes in heat resistance
US20100068405A1 (en) * 2008-09-15 2010-03-18 Shinde Sachin R Method of forming metallic carbide based wear resistant coating on a combustion turbine component
JP5760525B2 (en) * 2010-03-30 2015-08-12 Ｊｆｅスチール株式会社 Stainless steel foil and catalyst carrier for exhaust gas purification apparatus using the foil
CN114686759A (en) 2014-12-11 2022-07-01 山特维克知识产权股份有限公司 Ferritic alloy
RU2620405C1 (en) * 2016-03-24 2017-05-25 Открытое акционерное общество "Композит" Chromating alloy and method of alloy melting
CN106636963B (en) * 2016-10-21 2019-02-12 广东电网有限责任公司电力科学研究院 A kind of alloy material
CN108715971B (en) * 2018-05-31 2020-06-23 江苏省沙钢钢铁研究院有限公司 Iron-chromium-aluminum alloy vacuum smelting process
CN109825777B (en) * 2019-04-01 2021-01-08 江苏兄弟合金有限公司 Preparation method of high-toughness Fe-Cr-Al electrothermal alloy
CN113174531B (en) * 2021-03-31 2022-09-02 中北大学 Medium-chromium type iron-chromium-aluminum alloy and production method thereof
CN118202080A (en) * 2021-11-11 2024-06-14 康泰尔有限公司 FeCrAl powder and object produced therefrom
WO2023086006A1 (en) * 2021-11-11 2023-05-19 Kanthal Ab A ferritic iron-chromium-aluminum powder and a seamless tube made thereof

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4277374A (en) * 1980-01-28 1981-07-07 Allegheny Ludlum Steel Corporation Ferritic stainless steel substrate for catalytic system
US4414023A (en) * 1982-04-12 1983-11-08 Allegheny Ludlum Steel Corporation Iron-chromium-aluminum alloy and article and method therefor
DE3706415A1 (en) * 1987-02-27 1988-09-08 Thyssen Edelstahlwerke Ag SEMI-FINISHED FERRITIC STEEL PRODUCT AND ITS USE
EP0516097B1 (en) * 1991-05-29 1996-08-28 Kawasaki Steel Corporation Iron-chromium-aluminium alloy, catalytic substrate comprising the same and method of preparation
US5340415A (en) * 1992-06-01 1994-08-23 Sumitomo Metal Industries, Ltd. Ferritic stainless steel plates and foils and method for their production
DE19928842C2 (en) * 1999-06-24 2001-07-12 Krupp Vdm Gmbh Ferritic alloy
DE10157749B4 (en) * 2001-04-26 2004-05-27 Thyssenkrupp Vdm Gmbh Iron-chromium-aluminum alloy

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2933349A1 (en) * 2012-12-17 2015-10-21 JFE Steel Corporation Stainless steel sheet and stainless steel foil
EP2933349A4 (en) * 2012-12-17 2016-04-06 Jfe Steel Corp Stainless steel sheet and stainless steel foil

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