EP3821040B1 - Gleisteil aus hypereutektoidem stahl - Google Patents

Gleisteil aus hypereutektoidem stahl Download PDF

Info

Publication number
EP3821040B1
EP3821040B1 EP19752261.8A EP19752261A EP3821040B1 EP 3821040 B1 EP3821040 B1 EP 3821040B1 EP 19752261 A EP19752261 A EP 19752261A EP 3821040 B1 EP3821040 B1 EP 3821040B1
Authority
EP
European Patent Office
Prior art keywords
rail
steel
track part
hypereutectoid steel
head portion
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.)
Active
Application number
EP19752261.8A
Other languages
English (en)
French (fr)
Other versions
EP3821040A1 (de
Inventor
Jürgen GORIUPP
Mario Kuss
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.)
Voestalpine Rail Technology GmbH
Original Assignee
Voestalpine Rail Technology GmbH
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 Voestalpine Rail Technology GmbH filed Critical Voestalpine Rail Technology GmbH
Publication of EP3821040A1 publication Critical patent/EP3821040A1/de
Application granted granted Critical
Publication of EP3821040B1 publication Critical patent/EP3821040B1/de
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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
    • C22C38/02—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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/04—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for rails
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/08—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling structural sections, i.e. work of special cross-section, e.g. angle steel
    • B21B1/085—Rail sections
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/56—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering characterised by the quenching agents
    • C21D1/60—Aqueous agents
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/62—Quenching devices
    • C21D1/63—Quenching devices for bath quenching
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
    • 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
    • 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
    • C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/003—Cementite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/009—Pearlite
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
    • 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
    • C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
    • 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
    • C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium

Definitions

  • the invention relates to a track part, in particular a rail for rail vehicles, made of a hypereutectoid steel comprising a rail foot, a rail web and a rail head portion.
  • the invention further relates to a method for producing such a track part.
  • JP 2013 147725 A JP 2004 204306 A and WO 2017/2000096 A .
  • Hypereutectoid steels are known for producing rails, for example from EP 2388352 A1 .
  • the iron-carbon diagram shows an eutectoid at a carbon content (C content) of 0.77% by weight of carbon and at a temperature of 723°C, at which point a fixed direct phase transition from the austenite phase to the perlite phase occurs on cooling.
  • C content carbon content
  • Perlite is preferred over other steel modifications for rails in terms of wear resistance and elongation at break, as it is best for wear due to the lamellar structure.
  • the pearlitic structure comprises a ferrite phase, wherein the ferrite content in the perlite phase can be regarded as a tough and ductile phase and as a fixed variable, because the C-content of the rail steel varies only in very narrow limits, and the pearlitic structure further comprises a cementite phase, wherein the ferrite and the cemetite phases are arranged in lamellar relationship to each other.
  • secondary cementite precipitates are significantly influenced by a combination of alloying and heat treatment technology.
  • the knowledge of the precipitation temperature of the secondary cementite is of crucial importance and one should not fall below the precipitation temperature before the subsequent heat treatment.
  • the cooling rate during the heat treatment process should be as high as possible to suppress the precipitation of secondary cementite. Excessive levels of secondary cementite can adversely affect the breaking properties of steels, as the breaking behavior becomes increasingly intercrystalline.
  • Essential for the quality of a rail is thus a high wear resistance, for which essentially the hardness (for example indicated as Brinell hardness) of the rail is characteristic.
  • the desirable hardness inevitably goes hand in hand with a reduction in toughness, which is detrimental to the durability of the track part, especially in heavy load, where the rail is subjected to particularly high bending stresses when driving over a rail vehicle.
  • the invention is defined in the appended claims.
  • the invention therefore aims to improve a track part, in particular a rail, which is to consist of a low-alloy steel for reasons of cost and ease of welding, to the effect that due to a high hardness of the material even at elevated wheel loads, the wear resistance in the rail head is increased so far that a use time of longer than 30 years can be ensured.
  • the track part should be well weldable and have similar other material properties as proven steels used in the rail construction, such as e.g. a similar electrical conductivity and a similar coefficient of thermal expansion.
  • the invention aims to provide a simple manufacturing method for a track part according to the invention, which is characterized by a short process time (avoidance of incandescent phases), high reproducibility and high cost-effectiveness.
  • the method shall be suitable for producing long rails of e.g. over 100 m in length, with specification-compliant material properties over the entire rail length to be ensured.
  • the invention according to a first aspect provides a track part, in particular a rail of the type mentioned above, which is characterized in that a hypereutectoid steel with the following directional analysis is used::
  • this steel composition has proven to be extremely suitable, since a hardness in the range of 460 HB and higher could be achieved and the rail according to the invention at the same time has a sufficient elongation at break for the heavy load range.
  • the feature that at least in the head portion of the rail a pearlitic structure is substantially free of secondary cementite networks means that at most 5% of the existing secondary cementite precipitates are in the form of secondary cementite networks.
  • a secondary cementite network means a microstructure in which the former austenite grains are completely surrounded by a closed network of secondary cementite.
  • Secondary cementite precipitates reduce the carbon supply for the formation of pearlitic cementite lamellae needed for wear resistance. For these reasons, the suppression of secondary cementite in hypereutectoid rail steels is considered to be advantageous.
  • the concentration of manganese in the present steel is selected to shift the formation of embrittling secondary cementite to lower temperatures due to its austenite stabilizing effect, thereby enabling fine grain rolling at low rolling temperatures of hypereutectoid rail steels while suppressing secondary cementite precipitation.
  • the lower limit of 0.9 wt.-% manganese was chosen because the precipitation temperature of embrittling secondary cementite shifts to higher temperatures if one falls below this lower limit, which would result in that the suppression of the same can not be guaranteed in the subsequent heat treatment.
  • the upper limit of 1.35 wt.-% manganese was chosen to ensure castability of the steel.
  • the alloy composition of the present invention provides a lower limit of the carbon content of 0.98 wt% and an upper limit of 1.17 wt%.
  • the lower limit was chosen here in view of a sufficient strength, since carbon brings the required strength.
  • the upper limit was chosen in order to avoid the precipitation of secondary cementite networks, especially from a depth of approx. 5-10 mm below the rail head surface, even with a lower heat dissipation during forced cooling after rolling. If secondary cementite networks were formed in the interior of the rail head due to a too low heat dissipation or a too low cooling rate, the material properties would deteriorate significantly, so that a sufficient elongation at break, such as, for example, an elongation at break of at least 8%, could no longer be achieved.
  • the alloy composition of the invention provides for silicon a lower limit of 0.70 wt.-% and an upper limit of 1.10 wt.-%.
  • the lower limit was chosen to ensure the effectiveness of silicon to suppress embrittling secondary cementite precipitates. This extends the process window of the heat treatment so that a secondary cementite network can be avoided.
  • the upper limit is based on the background that, if this limit is exceeded, the required electrical conductivity of the rails would decrease in such a way that in some cases impairments in the signaling technology would be possible.
  • the alloy composition according to the invention provides for chromium a lower limit of 0.15 wt.-% and an upper limit of 0.70 wt.-%. It has been found that chromium, starting at a content of 0.15 wt.-%, has a marked effect on the crosssection hardening of the rail and suppresses the formation of secondary cementite, which in turn widens the process window of the heat treatment, so that the secondary cementite structure cannot be formed as a network.
  • the upper limit of 0.70 wt.-% was chosen because the weldability of the rail is made difficult or impossible with increasing chromium content.
  • the invention is based on a particular selection of the quantitative ranges of the individual alloy constituents, the individual alloying constituents having partially opposite effects.
  • a higher carbon content is desirable for achieving high strengths, but as the carbon content increases, the disadvantage of the increasing austenite-to-perlite-transition temperature has to be considered.
  • high silicon contents are responsible for the suppression of embrittling secondary cementite precipitates, they also increases the austenite-to-perlite-transition temperature.
  • secondary cementite precipitates at relatively high temperatures due to the relatively high carbon and silicon content, so that secondary cementite precipitates can occur in an enhanced form also prior to the heat treatment process.
  • the use of high carbon content in combination with silicon is actually counterproductive.
  • the directional analysis of the rail steel may be formed such that Al (aluminum) is additionally used in amounts of 0.01-0.06 wt.-%. This leads to a minimization of the pearlite grain size, which is beneficial to the elongation at break.
  • V vanadium
  • V vanadium
  • V vanadium
  • Al may additionally be used in amounts of from 0.07 to 0.20 wt.-%, in particular from 0.10 to 0.20 wt.-%, as in a preferred embodiment of the present invention. It has been found that already starting from a vanadium content of 0.07 wt.-%, an increase in strength and a grain refining effect may be achieved. The strength decreases again from the upper limit of 0.2 wt.-%, since too much C from the matrix is bound.
  • Nb niobium
  • Nb niobium
  • Ti titanium
  • Ti titanium
  • V is used in amounts of 0.07 to 0.20 wt.-%, in particular 0.10 to 0.2 wt.-%, together with Nb in amounts of 0.010 to 0.030 wt.-%.
  • Al is used in amounts of 0.01 - 0.06 wt.-% together with Nb in amounts of 0.01 - 0.03 wt.-%.
  • the grain refining effect can be increased by a nitrogen content set in the steel in the range of 40 to 120 ppm, which corresponds to a preferred embodiment of the present invention.
  • a steel quality is achieved which enables the production of a track part in which the steel, at least in the head portion of the rail, has a tensile strength greater than 1500 MPa, an elongation at break of greater than 8% and a Brinell hardness (according to EN ISO 6506-1) of greater than 460 HB, as corresponds to the present invention.
  • the inventive method for producing a track part according to the invention is characterized in that a hypereutectoid steel having a composition according to any one of claims 1 to 9 is taken from a furnace at a temperature of 1000 - 1300°C, then rolled at a final rolling temperature of 850 - 950°C and is then subjected to forced cooling to a temperature of 450°C to 600°C.
  • the furnace is preferably a walking beam furnace.
  • the steel with the composition according to the invention is removed from the furnace and rolled to the desired shape of the track part, in particular rail.
  • a final rolling temperature i.e. a temperature of the steel at the end of the rolling mill, of 850°C
  • secondary cementite precipitates at the perlite grain boundaries, especially in the formation of secondary cementite networks can lead to unacceptable embrittlement of the rail.
  • the conditions in the rolling mill are selected by means of the accumulated degree of transformation within continuous rolling passes on the finishing scale such that a recrystallizationcontrolled rolling process is achieved by means of deformation induced precipitations and precipitates in solution taking into account the forming speed of the reduction per pass, the temperature and the alloy composition, which allows to realize a small former austenite grain size of 8 ⁇ m to 35 ⁇ m, at least in the head portion of the rail. According to the invention this is followed by a rapid cooling to below 600°C, in which temperature range no secondary cementite is precipitated any more, creating a very wear-resistant fine-pearlitic microstructure with sufficient elongation at break for the heavy-duty application.
  • the forced cooling takes place at least in the head portion of the rail, in order to ensure at least there the pearlitic structure.
  • the cooling rate is chosen so high that a substantial suppression of secondary cementite precipitation takes place, but no formation of undesirable secondary phases such as wear-promoting bainite or martensite occurs.
  • the process according to the invention is preferably further developed in that the forced cooling takes place in a bath of cooling medium not being pure water.
  • a bath of cooling medium not being pure water With non-pure water cooling media evaporation effects on the surface to be cooled of the rail can be avoided, which leads on the one hand to improved heat transfer from the hot steel to the cooling medium and, consequently, in the interest of avoiding secondary cementite precipitates to a more rapid cooling, and on the other hand, suppresses the emergence of soft staining the surface of the rail.
  • a particularly effective cooling succeeds in the interest of avoiding secondary cementite precipitates, when the forced cooling takes place in a polymer bath with a temperature of 10 - 70°C, as provided according to a preferred embodiment of the present invention.
  • the method is carried out such that, to avoid secondary cementite precipitates, the forced cooling is performed at a rate of at least 4°C/sec, preferably at least 8°C/sec, more preferably at least 12°C/sec. In this way, the area of the formation of secondary cementite precipitates is quickly passed through in the iron-carbon diagram, so that the embrittlement of the rail steel can be effectively avoided.
  • a rail for railway vehicles was made of a hypereutectoid steel with the following directional analysis according to the method of the invention: 1.13 wt.-% C 1.28 wt.-% Mn 0.87 wt.-% Si 0.39 wt.-% Cr 0.15 wt.-% V 0.03 wt.-% Nb
  • a rail with a tensile strength of 1580 MPa/mm 2 , an elongation at break (A 5 ) of 8.5% and a hardness (RS) of 475 HB (Brinell hardness) was obtained.
  • a rail for railway vehicles was made of a hypereutectoid steel with the following directional analysis according to the method of the invention: 1.12 wt.-% C 1.10 wt.-% Mn 0.85 wt.-% Si 0.45 wt.-% Cr 0.15 wt.-% V 0.015 wt.-% Nb
  • a rail with a tensile strength of 1550 MPa/mm 2 , an elongation at break (A 5 ) of 9.2% and a hardness (RS) of 470 HB (Brinell hardness) was obtained.
  • a rail for railway vehicles was made of a hypereutectoid steel with the following directional analysis according to the method of the invention: 0.98 wt.-% C 1.15 wt.-% Mn 0.95 wt.-% Si 0.55 wt.-% Cr
  • a rail with a tensile strength of 1515 MPa/mm 2 , an elongation at break (A 5 ) of 9.7% and a hardness (RS) of 463 HB (Brinell hardness) was obtained.
  • a rail for railway vehicles was made of a hypereutectoid steel with the following directional analysis according to the method of the invention: 1.01 wt.-% C 0.90 wt.-% Mn 0.90 wt.-% Si 0.53 wt.-% Cr
  • a rail with a tensile strength of 1500 MPa/mm 2 , an elongation at break (A 5 ) of 9.6% and a hardness (RS) of 460 HB (Brinell hardness) was obtained.
  • a rail for railway vehicles was made of a hypereutectoid steel with the following directional analysis according to the method of the invention: 1.06 wt.- % C 1.20 wt.-% Mn 0.95 wt.-% Si 0.56 wt.-% Cr 0.15 wt.-% V 0.015 wt.-% Nb
  • a rail with a tensile strength of 1570 MPa/mm 2 , an elongation at break (A 5 ) of 9.2% and a hardness (RS) of 478 HB (Brinell hardness) was obtained.
  • the rails produced according to Examples 1 to 5 have a purely pearlitic microstructure essentially free of secondary cementite networks according to Fig. 1
  • the rail material microstructure at least in the standard tensile test position of the rail (10 mm below the running edge), has a pearlitic structure below 3%-nital-etching substantially free of secondary cementite networks corresponding to the classification chart in Fig. 3 .
  • the cementite lamella thickness is significantly increased in the case of the rail according to the invention compared with a rail from the prior art (rail R400HT according to EN 13674-1), as can be seen from Fig. 2 .
  • the degree of secondary cementite itself can be assessed with the aid of a classification chart for assessing the secondary cementite precipitates on the microstructure, as shown in Fig. 3 .
  • the wear resistance of rails corresponding to the examples was measured by means of a test device according to AT 409766 B (wheel-rail test bench) and compared with that of conventional rail steels according to EN 13674-1 ( Fig. 4 ).

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Steel (AREA)
  • Heat Treatment Of Articles (AREA)

Claims (8)

  1. Gleisteil, insbesondere Schiene für Schienenfahrzeuge, aus einem hypereutektoiden Stahl mit einem Schienenfuß, einem Steg und einem Kopfbereich, wobei Stahl mit der folgenden Richtanalyse eingesetzt ist: 0,98 - 1,17 Gew.-% C 0,90 - 1,35 Gew.-% Mn 0,70 - 1,10 Gew.-% Si 0,15 - 0,70 Gew.-% Cr
    und der Stahl zumindest im Kopfbereich der Schiene ein perlitisches Gefüge aufweist, das im Wesentlich frei von Sekundärzementit-Netzwerken ist, wobei höchstens 5% der vorhandenen Sekundärzementit-Ausscheidungen in Form von Sekundärzementit-Netzwerken vorliegen, wobei der hypereutektoide Stahl zusätzlich optional Al in Mengen von 0,01 - 0,06 Gew.-% und optional V in Mengen von 0,07 - 0,20 Gew.-%, insbesondere 0,10 bis 0,20 Gew.-% und optional Nb in Mengen von 0,01 - 0,03 Gew.-% und optional Ti in Mengen von 0,015 - 0,05 Gew.-% enthält, wobei der hypereutektoide Stahl zumindest im Kopfbereich der Schiene eine Zugfestigkeit größer als 1500 MPa, eine Bruchdehnung von größer als 8% sowie eine Brinell-Härte von größer als 460 HB aufweist.
  2. Gleisteil nach Anspruch 1, dadurch gekennzeichnet, dass C in Mengen von 1,05 - 1,17 Gew.-%, bevorzugt 1,06 - 1,15 Gew.-%, und besonders bevorzugt 1,08 Gew.-% eingesetzt ist.
  3. Gleisteil nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass der hypereutektoide Stahl zusätzlich N im Bereich von 40 bis 120ppm enthält.
  4. Verfahren zur Herstellung eines Gleisteils nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass ein hypereutektoider Stahl mit einer Zusammensetzung nach einem der Ansprüche 1 bis 3 bei einer Temperatur von 1000 - 1300°C aus einem Ofen entnommen wird, hierauf bei 850 - 950°C Endwalztemperatur gewalzt und anschließend einer Zwangskühlung auf eine Temperatur von 450°C bis 600°C unterworfen wird, wobei die Zwangskühlung mit einer Rate von zumindest 4°C/sek., bevorzugt zumindest 8°C/sek., besonders bevorzugt zumindest 12°C/sek. erfolgt.
  5. Verfahren nach Anspruch 4, dadurch gekennzeichnet, dass die Umformung im Temperaturbereich 1000-850°C zumindest im Kopfbereich der Schiene einen akkumulierten Vergleichsumformgrad von min 1.4 aufweist.
  6. Verfahren nach Anspruch 4 oder 5, dadurch gekennzeichnet, dass die Zwangskühlung zumindest im Kopfbereich der Schiene erfolgt.
  7. Verfahren nach einem der Ansprüche 4 bis 6, dadurch gekennzeichnet, dass die Zwangskühlung in einem Bad mit einem nichtreinwässrigen Kühlmedium erfolgt.
  8. Verfahren nach einem der Ansprüche 4 bis 7, dadurch gekennzeichnet, dass die Zwangskühlung in einem Polymerbad mit einer Temperatur von 15 - 50°C erfolgt.
EP19752261.8A 2018-07-10 2019-07-03 Gleisteil aus hypereutektoidem stahl Active EP3821040B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ATA201/2018A AT521405B1 (de) 2018-07-10 2018-07-10 Gleisteil aus einem hypereutektoiden Stahl
PCT/IB2019/055660 WO2020012297A1 (en) 2018-07-10 2019-07-03 Track part made of a hypereutectoid steel

Publications (2)

Publication Number Publication Date
EP3821040A1 EP3821040A1 (de) 2021-05-19
EP3821040B1 true EP3821040B1 (de) 2023-08-30

Family

ID=67551584

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19752261.8A Active EP3821040B1 (de) 2018-07-10 2019-07-03 Gleisteil aus hypereutektoidem stahl

Country Status (13)

Country Link
US (1) US20200017943A1 (de)
EP (1) EP3821040B1 (de)
AR (1) AR115726A1 (de)
AT (1) AT521405B1 (de)
AU (1) AU2019204857A1 (de)
BR (1) BR102019014230B1 (de)
CA (1) CA3048723C (de)
ES (1) ES2834057T3 (de)
MA (1) MA53132A (de)
PL (1) PL3821040T3 (de)
UA (1) UA127116C2 (de)
WO (1) WO2020012297A1 (de)
ZA (1) ZA202006996B (de)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2021302317B2 (en) * 2020-06-29 2023-11-16 Jfe Steel Corporation Rail having excellent fatigue crack propagation resistance characteristics, and method for producing same
CN115094338B (zh) * 2022-07-27 2023-09-22 内蒙古科技大学 一种过共析钢轨用钢及其制备方法

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2112051C1 (ru) * 1994-11-15 1998-05-27 Ниппон Стил Корпорейшн Рельс из перлитной стали с высокой износостойкостью и способ производства рельса
DE19906694C2 (de) 1999-02-18 2002-04-11 Lueraflex Gmbh G Lueckenotto Breitstreckwalze
JP2002256393A (ja) * 2001-02-28 2002-09-11 Nippon Steel Corp 耐破壊性に優れた耐摩耗パーライト系レール
EP1493831A4 (de) 2002-04-05 2006-12-06 Nippon Steel Corp Auf perlit basierende schiene mit hervorragender abriebfestigkeit und duktilität und verfahren zu ihrer herstellung
JP4272410B2 (ja) * 2002-11-12 2009-06-03 新日本製鐵株式会社 パーライトレールの熱処理方法
JP4336101B2 (ja) * 2002-12-25 2009-09-30 新日本製鐵株式会社 耐摩耗性および靭性に優れた高炭素パーライト系レール
JP5145795B2 (ja) * 2006-07-24 2013-02-20 新日鐵住金株式会社 耐摩耗性および延性に優れたパーライト系レールの製造方法
ITMI20072244A1 (it) * 2007-11-28 2009-05-29 Danieli Off Mecc Dispositivo per trattamento termico di rotaie e relativo processo
EP2400040B1 (de) * 2009-02-18 2015-11-25 Nippon Steel & Sumitomo Metal Corporation Perlitschiene mit hervorragender veschleissbeständigkeit und festigkeit
CN102803536B (zh) * 2009-06-26 2015-01-28 新日铁住金株式会社 延展性优良的珠光体系高碳钢钢轨及其制造方法
JP5776565B2 (ja) * 2012-01-23 2015-09-09 新日鐵住金株式会社 レール鋼及び車輪鋼の材質選択方法
US9534278B2 (en) * 2012-06-14 2017-01-03 Nippon Steel & Sumitomo Metal Corporation Rail
US10995396B2 (en) * 2016-05-19 2021-05-04 Nippon Steel Corporation Rail

Also Published As

Publication number Publication date
ZA202006996B (en) 2021-10-27
EP3821040A1 (de) 2021-05-19
ES2834057T3 (es) 2024-03-26
ES2834057T1 (es) 2021-06-16
BR102019014230A2 (pt) 2020-02-27
WO2020012297A1 (en) 2020-01-16
AT521405A1 (de) 2020-01-15
BR102019014230B1 (pt) 2023-10-31
CA3048723A1 (en) 2020-01-10
CA3048723C (en) 2021-11-09
PL3821040T3 (pl) 2024-02-12
AR115726A1 (es) 2021-02-17
AU2019204857A1 (en) 2020-01-30
AT521405B1 (de) 2021-09-15
MA53132A (fr) 2021-05-19
US20200017943A1 (en) 2020-01-16
UA127116C2 (uk) 2023-05-03

Similar Documents

Publication Publication Date Title
EP2135966B1 (de) Perlitstahlschiene mit hoher innerer härte mit hervorragender verschleissbeständigkeit und ermüdungsbeständigkeit sowie herstellungsverfahren dafür
JP5292875B2 (ja) 耐摩耗性，耐疲労損傷性および耐遅れ破壊性に優れた内部高硬度型パーライト鋼レールおよびその製造方法
AU2016200056B2 (en) High-Strength and Highly Fatigue-Resistant Steel Rail and Production Method Thereof
US20170191149A1 (en) Railway vehicle wheel and method for manufacturing railway vehicle wheel
JP5282506B2 (ja) 耐摩耗性と耐疲労損傷性に優れた内部高硬度型パーライト鋼レールおよびその製造方法
CN110607488A (zh) 一种高速铁路用在线热处理钢轨及其制造方法
EP3821040B1 (de) Gleisteil aus hypereutektoidem stahl
EP3778961B1 (de) Schiene und verfahren zur herstellung davon
KR20050075033A (ko) 용접용 강 빌딩 구성요소 및 그 제조방법
KR101010595B1 (ko) 용접용 강 빌딩 구성요소 및 그 제조방법
JP4736790B2 (ja) 高強度パーライト系レールおよびその製造方法
JP6555447B2 (ja) レールの製造方法
JP2008050684A (ja) 耐遅れ破壊特性に優れる高強度パーライト系鋼レール
JPWO2018174095A1 (ja) レールおよびその製造方法
OA20006A (en) Track Part Made of a Hypereutectoid Steel.
JP3832169B2 (ja) 耐摩耗性と延靭性に優れたパーライト鋼レールの製造方法
CN113557312A (zh) 钢轨
WO2022004247A1 (ja) 耐疲労き裂伝播特性に優れるレールおよびその製造方法
JP6822575B2 (ja) レールおよびその製造方法
JP2005163088A (ja) 耐摩耗性および延性に優れた高炭素鋼レールの製造方法

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20210113

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: ES

Ref legal event code: BA2A

Ref document number: 2834057

Country of ref document: ES

Kind code of ref document: T1

Effective date: 20210616

RAV Requested validation state of the european patent: fee paid

Extension state: TN

Effective date: 20210113

Extension state: MA

Effective date: 20210113

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20220216

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20230321

GRAJ Information related to disapproval of communication of intention to grant by the applicant or resumption of examination proceedings by the epo deleted

Free format text: ORIGINAL CODE: EPIDOSDIGR1

GRAL Information related to payment of fee for publishing/printing deleted

Free format text: ORIGINAL CODE: EPIDOSDIGR3

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

P01 Opt-out of the competence of the unified patent court (upc) registered

Effective date: 20230523

INTC Intention to grant announced (deleted)
INTG Intention to grant announced

Effective date: 20230616

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602019036196

Country of ref document: DE

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: SE

Ref legal event code: TRGR

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20230830

REG Reference to a national code

Ref country code: NO

Ref legal event code: T2

Effective date: 20230830

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231230

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231230

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231201

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2834057

Country of ref document: ES

Kind code of ref document: T3

Effective date: 20240326

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230830

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20240102