US20200199703A1 - Track part and method for producing a track part - Google Patents

Track part and method for producing a track part Download PDF

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US20200199703A1
US20200199703A1 US16/616,663 US201816616663A US2020199703A1 US 20200199703 A1 US20200199703 A1 US 20200199703A1 US 201816616663 A US201816616663 A US 201816616663A US 2020199703 A1 US2020199703 A1 US 2020199703A1
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track part
cooling
temperature
rail
vol
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Christoph KAMMERHOFER
Hans Peter BRANTNER
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Voestalpine Rail Technology GmbH
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    • 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
    • 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
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted quenching
    • C21D1/20—Isothermal quenching, e.g. bainitic hardening
    • 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
    • C21D11/00—Process control or regulation for heat treatments
    • C21D11/005—Process control or regulation for heat treatments for cooling
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/002—Heat treatment of ferrous alloys containing Cr
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/005—Heat treatment of ferrous alloys containing Mn
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/008—Heat treatment of ferrous alloys containing Si
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—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
    • C22C38/02—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
    • C22C38/18—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
    • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
    • 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
    • C21D2211/001—Austenite
    • 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
    • C21D2211/002—Bainite
    • 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
    • C21D2211/005—Ferrite
    • 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
    • C21D2211/008—Martensite
    • E—FIXED CONSTRUCTIONS
    • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
    • E01B—PERMANENT WAY; PERMANENT-WAY TOOLS; MACHINES FOR MAKING RAILWAYS OF ALL KINDS
    • E01B5/00—Rails; Guard rails; Distance-keeping means for them
    • E01B5/02—Rails

Definitions

  • the invention relates to a track part, in particular a low-alloy steel rail for rail vehicles.
  • the invention further relates to a method for producing a track part from a hot-rolled section.
  • the wear rate occurring parallelly with the crack growth is always smaller both with the classic, completely perlitic rail grades and with the bainitic rail grades, crack growth thus actually dominating.
  • Bainite is a microstructure that can form during the thermal treatment of carbonaceous steel by isothermal transformation or continuous cooling. Bainite forms at temperatures and cooling rates ranging between those of perlite formation and martensite formation. Unlike with the formation of martensite, shearing processes in the crystal lattice and diffusion processes are coupled in this case, thus providing different transformation mechanisms. Due to the dependency on cooling rates, carbon contents, alloying elements and thus resulting formation temperatures, bainite has no characteristic microstructure.
  • Bainite like perlite, comprises the phases ferrite and cementite (Fe3C), yet differs from perlite in terms of form, size and distribution. Basically, distinction is made between two main microstructural forms, i.e. upper bainite and lower bainite.
  • a method for producing a track part and a rail steel which aims at an improvement of the wear resistance, in particular the avoidance of head checks, and to this end comprises a microstructure with a multi-phase bainite structure having a ferrite content of 5-15% at the rail head.
  • a microstructure with a multi-phase bainite structure having a ferrite content of 5-15% at the rail head.
  • the invention aims to improve a track part, in particular a rail, to be comprised of a low-alloy steel for cost reasons and for welding reasons to the effect that, even with elevated wheel loads and larger curves, the formation of cracks will be restrained, on the one hand, and the initial crack growth will be clearly delayed while preventing the crack path from entering the interior of the rail, on the other hand.
  • the track part is to be readily weldable and exhibit similar other material properties, such as a similar electrical conductivity and a similar thermal expansion coefficient, as steels hitherto proven in railway construction.
  • the invention according to a first aspect provides a track part of the initially defined kind, which is further developed such that the steel comprises, in the rail head of the track part, a ferrite portion of 5-15 vol %, an austenite portion of 5-20 vol %, a martensite portion of 5-20 vol %, and a portion of carbide-free bainite of 55-75 vol %.
  • Carbide-free bainite is comprised of ferrite needles with a high dislocation density without carbide precipitations.
  • the austenitic phase portions in the contact-influenced zone are subject to another deformation mechanism than in the case of conventional carbide-containing rails.
  • a particularly good crack resistance will be achieved if the portion of the carbide-free bainite is 60-70 vol %.
  • the ferrite portion is preferably 8-13 vol %.
  • the bainite forms a matrix in which austenite, martensite and ferrite are preferably homogenously distributed.
  • Austenite and martensite are preferably at least partially present in island form, either polygonally or globularly with an average size of several ⁇ m, in particular in a range of 1-10 ⁇ m.
  • austenite is preferably partially present in film form with a thickness of less than 1 ⁇ m and a length of several ⁇ m.
  • Martensite in particular, is partially present as pure martensite in a very low or hardly tempered morphology such that carbide precipitations from martensite will hardly occur.
  • the size of the individual martensitic regions is about 5 ⁇ m.
  • Ferrite is present partially as grain boundary ferrite and partially as polygonal ferrite. Moreover, the inadvertent grain boundary perlite occurs primarily in the interior of the rail head, because there its occurrence is enabled by a cooling rate that is slightly lower than in the edge zone, which comprises several millimeters.
  • the low-alloy steel in the context of the invention preferably comprises as alloying components carbon, silicon, manganese, chromium, molybdenum and optionally vanadium, phosphorus, sulfur, boron, titanium, aluminum and/or nitrogen, and the balance iron.
  • no alloying component is present in an amount larger than 1.8 wt %.
  • silicon is present in an amount smaller than 1.2 wt %.
  • silicon is added by alloying in order to prevent the formation of cementite.
  • the silicon-carbon ratio is of particular relevance, since partial cementite formation may occur in the event of too small a Si content.
  • carbides per se are not desired in the sought multi-phase microstructure, on the other hand less carbon is available for the stabilization of austenite due to the formation of carbide, which will subsequently facilitate the formation of martensite. This is also undesired.
  • a minimum content of 1.5 wt % silicon is indicated to prevent the formation of cementite at mean carbon contents of around 0.3 wt %.
  • the silicon content is, however, limited to 1.20 wt %, since silicon allows the electrical resistance to strongly increase, thus possibly causing problems with the current recirculation in the track.
  • carbon is present in an amount smaller than 0.6 wt %, preferably smaller than 0.35 wt %.
  • Carbon is that element which influences the martensite starting temperature most. An increasing carbon portion will lead to a decrease of the martensite starting temperature.
  • the martensite starting temperature should not be much higher than 320° C. in order to avoid the occurrence of major martensite portions during the heat treatment and further cooling on the cooling bed.
  • the advantage of a lower carbon portion consists in that the austenite can absorb more carbon and the formation of bainite can occur to a larger extent. Moreover, the risk of an unwanted cementite formation is reduced.
  • Manganese is, above all, added by alloying in order to counteract the formation of ferrite and perlite during the heat treatment and to adjust mainly carbide-free bainite by increasing the hardenability.
  • Manganese is also an austenite stabilizer and, besides carbon, lowers the martensite starting temperature. From the literature, it is, moreover, known that the T0′ curve will shift towards lower carbon contents with increasing manganese contents, which counteracts the continuous formation of carbide-free bainite. For this reason, the maximum Mn content is limited to 1.8%, yet is preferably clearly lower for the above-cited reasons.
  • chromium Like manganese, chromium also increases the hardenability, yet has a stronger effect than manganese. In addition, chromium causes mixed crystal hardening, which is deliberately utilized. Relatively low chromium contents are sought to prevent the occurrence of chromium carbides, on the one hand, and to facilitate weldability, on the other hand.
  • Vanadium is a microalloying element that increases hardness without deteriorating toughness. In addition to mixed crystal hardening, the precipitation of very fine particles inducing an increase of the hardness is also caused.
  • molybdenum increases hardness.
  • the particularity of molybdenum is that, above all, the diffusion-controlled transformation products, i.e. ferrite and perlite, are shifted towards extended transformation periods, which in the literature is attributed to the solute drag effect. Thereby, the bainite area can be directly targeted even during continuous cooling.
  • Molybdenum has a negative effect on the segregation behavior such that the segregated regions are markedly enriched with molybdenum and, in the end, will have a martensitic microstructure.
  • the weldability is also markedly deteriorated by molybdenum. For these two reasons, the molybdenum content is kept as low as possible in order to adjust a predominantly carbide-free microstructure in combination with the heat treatment.
  • titanium is additionally alloyed to the steel, since the affinity to nitrogen is clearly higher with titanium than with boron, thus causing the precipitation of titanium carbonitrides.
  • the ratio of titanium to nitrogen which is always present in the melt at about 50-100 ppm, has to be at least 4:1 so that all of the nitrogen will be bound.
  • a problem resulting therefrom is the precipitation of possibly coarse titanium carbonitrides, which may have adverse effects on the toughness and fatigue properties.
  • a low-alloy steel having the following reference analysis is used:
  • a particularly good aptitude for highly stressed track sections is preferably provided if the track part has a tensile strength R m of 1150-1400 N/mm 2 in the head region. Moreover, the track part has a hardness of preferably 320-380 HB in the head region.
  • the invention provides a method for producing the above-described track part, in which the track part is produced from a hot-rolled section, wherein the rail head of the rolled section, immediately after having left the rolling stand, is subjected at rolling heat to controlled cooling, said controlled cooling comprising in a first step cooling at ambient air until reaching a first temperature of 780-830° C., in a second step accelerated cooling to a second temperature of 450-520° C., in a third step holding the second temperature, in a fourth step further accelerated cooling until reaching a third temperature of 420-470° C., in a fifth step holding the third temperature, and in a sixth step cooling to room temperature at ambient air.
  • Said controlled cooling preferably is performed by immersing at least the rail head into a liquid coolant as known per se.
  • Said accelerated cooling in the liquid coolant allows for the selective achievement of the desired temperature ranges in a short time without passing through undesired phase areas.
  • said accelerated cooling in the second step is performed at a cooling rate of 2-5° C./s.
  • the track part is completely immersed into the coolant during the second step.
  • the step of holding between 450° C.-520° C. is to primarily provide a temperature compensation between the rail head surface in contact with the coolant and the rail head interior in order to keep stronger reheating in the second holding step (fifth step) low.
  • this temperature range offers the following special feature to the steel having the above-identified chemical composition:
  • the extent of ferrite formation, if any, can be influenced by the cooling speed (and hence the time until reaching the temperature range) and by the residence time in this temperature range. In some circumstances, the formation of grain boundary perlite may occur in this temperature range.
  • the third step extends over a period of 10-300 s, preferably 30-60 s.
  • said accelerated cooling in the fourth step is performed at a cooling rate of 2-5° C./s.
  • the track part is immersed into the coolant only with the rail head.
  • the second step of holding between 420° C.-470° C. serves the formation of the carbide-free bainite with a simultaneously running carbon redistribution into the surrounding austenite.
  • the austenite is primarily present as island type rather than film type.
  • the intensity of the carbon redistribution in this range determines how strongly the austenite can be enriched with carbon and will remain metastable as austenite or transform martensitically during further cooling.
  • a temperature not lower than 400° C. will be observed during accelerated cooling (fourth step), since otherwise the formation of the lower bainite step accompanied by fine cementite precipitations will be caused.
  • the third step extends over a period of 50-600 s, preferably 100-270 s.
  • the adjustment of the two holding steps can be effected by cooling to the lower limit of the temperature range followed by reheating.
  • the track part is held in a position removed from the coolant during the third and/or fifth steps.
  • the value of the first temperature and the value of the second temperature have to be precisely determined a priori for the respective steel.
  • the temperature of the rail is continuously measured during controlled cooling, wherein the cooling and holding stages are respectively started or terminated when reaching the respective temperature thresholds.
  • the surface temperature of the rail may vary over the entire length of the track part, yet cooling is uniformly performed for the whole track part, it is preferably proceeded such that the temperature is detected at a plurality of measuring points distributed over the length of the track part and a mean value of the temperature is formed, which is used for controlling said controlled cooling.
  • the coolant passes three phases of the quenching process.
  • the first phase i.e. the vapor film phase
  • the temperature on the surface of the rail head is so high that the coolant evaporates rapidly, thus causing the formation of a thin insulating vapor film (Leidenfrost effect).
  • This vapor film phase i.a., is highly dependent on the vapor formation heat of the coolant, the surface condition of the track part, e.g. cinders, or the chemical composition and design of the cooling tank.
  • the second phase the boiling phase, the coolant comes into direct contact with the hot surface of the rail head and immediately starts to boil, thus causing a high cooling speed.
  • the third phase the convection phase, starts as soon as the surface temperature of the track part has dropped to the boiling point of the coolant. In this range, the cooling speed is substantially influenced by the flow speed of the coolant.
  • the transition from the vapor film phase to the boiling phase usually takes place in a relatively uncontrolled and spontaneous manner. Since the rail temperature is subject to certain production-related temperature fluctuations over the entire length of the track part, the problem exists that the transition from the vapor film phase to the boiling phase occurs at different times in different longitudinal zones of the track part. This would lead to the formation of a non-uniform microstructure over the length of the track part, and hence to non-uniform material properties.
  • a preferred mode of operation provides that during the third step a film-breaking, gaseous pressure medium such as nitrogen is supplied to the rail head along the entire length of the track part to break the vapor film along the entire length of the track part and initiate the boiling phase.
  • a film-breaking, gaseous pressure medium such as nitrogen is supplied to the rail head along the entire length of the track part to break the vapor film along the entire length of the track part and initiate the boiling phase.
  • the film-breaking, gaseous pressure medium is supplied to the rail head about 20-100 s, in particular about 50 s, after the beginning of the second and/or fourth steps.
  • a low-alloy steel having the following reference analysis was formed by hot-rolling to a running rail with a standard rail section:
  • the rail was subjected at rolling heat to controlled cooling. Said controlled cooling is explained in more detail below with reference to the time-temperature transformation diagram depicted in FIG. 1 , wherein the line denoted by 1 represents the cooling course.
  • the rail is cooled to a temperature of 810° C. at ambient air.
  • the rail is immersed into the liquid coolant over its entire length and by its entire cross section, and a cooling rate of 4° C./s was adjusted. After about 85 s, the rail was removed from the cooling bath, and an initial surface temperature of the rail head of 470° C. was measured, point 2 having been reached.
  • the rail was held in a position removed from the coolant. Reheating to a temperature of 500° C. occurred within the first 5 seconds.
  • the rail was again immersed into the cooling bath and cooled to 440° C. (point 4 ) at a cooling rate of 4° C./s. This temperature was held for 100 seconds.
  • the rail was cooled to room temperature at ambient air.
  • the microstructure is illustrated in FIG. 2 .
  • the following material properties were measured:
  • a low-alloy steel having the following reference analysis was formed by hot-rolling to a running rail with a standard rail section:
  • the heat treatment was performed as in Example 1.
  • Example 2 In order to raise the wear resistance relative to that of Example 1 (0.3 wt % C), yet, at the same time, maintain the break resistance, a material having a significantly higher carbon content (0.5 wt %) was used in Example 2.
  • the advantage of a higher carbon content resides in enabling an enhanced enrichment both in the austenite and in the martensite, thus strengthening these two microstructural components, which has a very positive effect on the wear resistance.
  • the heat treatment (accelerated cooling), due to the higher carbon content, reduces the increased inclination to perlite formation—i.e. the region where perlite formation takes place is passed through very quickly such that no significant amounts of perlite can precipitate on the rail head surface (as far as to a depth of 10 mm). This means that the microstructure continues to comprise the previously indicated microstructural components.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
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  • Metallurgy (AREA)
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  • Crystallography & Structural Chemistry (AREA)
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ATA240/2017A AT519669B1 (de) 2017-06-07 2017-06-07 Gleisteil und Verfahren zur Herstellung eines Gleisteils
ATA240/2017 2017-06-07
PCT/AT2018/000049 WO2018223160A1 (de) 2017-06-07 2018-05-29 Gleisteil und verfahren zur herstellung eines gleisteils

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EP (1) EP3478861B1 (zh)
JP (1) JP7068347B2 (zh)
CN (1) CN110691856B (zh)
AT (1) AT519669B1 (zh)
AU (1) AU2018280322B2 (zh)
CA (1) CA3061470C (zh)
ES (1) ES2715051T3 (zh)
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