WO2015146150A1 - レールおよびその製造方法 - Google Patents
レールおよびその製造方法 Download PDFInfo
- Publication number
- WO2015146150A1 WO2015146150A1 PCT/JP2015/001659 JP2015001659W WO2015146150A1 WO 2015146150 A1 WO2015146150 A1 WO 2015146150A1 JP 2015001659 W JP2015001659 W JP 2015001659W WO 2015146150 A1 WO2015146150 A1 WO 2015146150A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- rail
- less
- rolling
- hardness
- variation
- Prior art date
Links
Images
Classifications
-
- 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
- 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
- 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
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
-
- 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
- C22C38/24—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
-
- 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
- C22C38/34—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of 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
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
-
- 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
- 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
- C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel 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
- C22C38/40—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
Definitions
- the present invention relates to a rail, in particular, a rail having a high hardness and a small variation in hardness, and a method for manufacturing the rail.
- the loading weight is heavier than that of passenger cars, so the load applied to the axle of the freight car is high, and the contact environment between the rail and the wheel is very severe.
- the rail used in such an environment is required to have wear resistance, and conventionally, steel having a pearlite structure is used.
- Patent Document 1 Patent Document 2, Patent Document 3 and Patent Document 4 disclose a hypereutectoid rail having an increased amount of cementite and a method for producing the same.
- Patent Document 5 Patent Document 6 and Patent Document 7 disclose a technique for increasing the hardness by refining the lamellar spacing of the pearlite structure for the eutectoid carbon level steel.
- Patent Document 8 discloses that the rolling between the rail steel slabs is finished rolling with the final finish at the head surface temperature of 850 ° C to 1050 ° C, and the time between passes is 3 seconds or more and 1 minute or less. After that, the final finishing rolling of one pass or multiple passes is performed at a head surface temperature of 800 ° C to 950 ° C with a reduction rate of 10% or less per pass, and then a cooling rate of 2 to 10 for 0.1 to 10 seconds.
- Patent Document 9 carbon steel or low alloy steel containing C: 0.60 to 1.00% is roughly rolled into a rail shape, and then the surface temperature of the rail is between 850 and 1000 ° C. per pass. Rolling with a reduction in cross-section of 5-30% is continuously finished and rolled for 3 seconds or more and the interval between rolling passes is 10 seconds or less. After that, it is allowed to cool or from 700 ° C to 700-500 ° C.
- Patent Document 10 discloses a steel strip for rail rolling containing, by mass, C: 0.65 to 1.20%, Si: 0.05 to 2.00%, Mn: 0.05 to 2.00%, and the balance being Fe and inevitable impurities.
- a method for producing a pearlite-based rail having excellent wear resistance and ductility by performing at least rough rolling and finish rolling in which the rail head surface is 900 ° C. or lower to Ar 3 transformation.
- the cumulative area reduction of the head was divided by 20% or more, and the reaction force value of the rolling mill was divided by the reaction force value at the same cumulative area reduction ratio and rolling temperature of 950 ° C.
- Rails for high-axle railways mainly freight transportation and mining railways, are required to have excellent wear resistance in order to improve the durability of the rails. Has been proposed.
- the rail is manufactured by hot rolling a steel material, the length of which is 100 m or more, and depending on the manufacturing method, there is a variation in hardness in the rail length direction. In some cases, sufficient effects cannot be exhibited due to wear. For this reason, it is extremely important to reduce the variation in hardness in the rolling longitudinal direction, but there is no description in Patent Documents 1 to 10 regarding the variation in hardness.
- an object of the present invention is to propose a rail that secures excellent wear resistance by suppressing variations in hardness in the rail length direction, together with its manufacturing method.
- the inventors collected specimens to be subjected to a rail wear test from steel materials having pearlite structures corresponding to rails having different hardnesses, and conducted a wear test to investigate the relationship between hardness and wear amount.
- the survey results are shown in FIG.
- the wear test was a comparative test simulating actual contact conditions between pearlite steel rails and wheels using a Nishihara type wear tester that can evaluate wear resistance in a short time. That is, as shown in FIG. 2, the test is performed by rotating the Nishihara type abrasion test piece 1 having an outer diameter of 30 mm, which is collected from the rail head, in contact with the tire test piece 2.
- the arrows in the figure indicate the rotation directions of the Nishihara type abrasion test piece 1 and the tire test piece 2, respectively.
- the tire test piece For the tire test piece, a round bar with a diameter of 32 mm is taken from the head of the normal rail described in JIS standard E1101, the Brinell hardness (Brinell load 29.4 kN) is HB370, and the structure becomes a tempered martensite structure. Heat treatment was performed, and then the shape shown in FIG. 2 was processed to obtain a tire test piece.
- the Nishihara type abrasion test piece 1 is sampled from two places on the rail head 3 as shown in FIG. A sample collected from the surface layer of the rail head 3 is a Nishihara type wear test piece 1a, and a sample collected from the inside is a Nishihara type wear test piece 1b.
- the center in the longitudinal direction of the Nishihara-type abrasion test piece 1b taken from the inside of the rail head 3 is located at a depth of 24 to 26 mm (average value 25 mm) from the upper surface of the rail head 3.
- the test environment is dry, contact pressure: 1.2 GPa, slip rate: -10%, rotation speed: 750 rpm (tire test piece is 750 rpm), and measure the wear after 1.8 ⁇ 10 5 revolutions. The amount of wear was calculated by measuring the weight of the test piece before and after the test and calculating the difference.
- the wear resistance increases as the hardness increases.
- the hardness of the rail is HB400 or more
- the wear resistance can be improved by 15% compared to a general heat treatment rail (HB370).
- HB370 general heat treatment rail
- the wear amount changes from 0.37 g to 0.3 g, so the wear amount variation is within 20%. is there.
- the change in wear amount should be changed from 0.40g to 0.27g.
- the variation is 33%.
- the variation in the hardness in the rail length direction is preferably a variation in wear amount within 20% in consideration of the results of the above-described wear test, and the variation in surface hardness is within ⁇ HB15. It has been found that excellent wear resistance in the direction is ensured and contributes to the improvement of the rail life, and the present invention has been completed.
- the gist configuration of the present invention is as follows. (1) In mass%, C: 0.60 to 1.0%, Si: 0.1-1.5% Mn: 0.01-1.5% P: 0.035% or less, S: 0.030% or less and Cr: 0.1-2.0% And the balance has a composition of Fe and inevitable impurities, and the rail head has a variation in surface hardness of ⁇ HB15 points or less in the rail length direction.
- the variation in the surface hardness in the rail length direction is the average value calculated from the measurement results obtained by measuring the Brinell hardness over the entire rail length (for example, 25 to 100 m) at a pitch of 5 m in the rolling length direction at the rail top. And the value of the Brinell hardness at each measurement point.
- the variation in surface hardness in the rail length direction is ⁇ HB15 points or less. All hardness values measured at a pitch of 5m (6 points for a total length of 25m, 11 points for a total length of 50m, In the case of a total length of 100 m, the average value of Brinell hardness is obtained from the measurement value of 21 points), and the difference between the average value and the Brinell hardness at each measurement point is within ⁇ 15 points at the maximum.
- the decarburized layer is previously removed by 0.5 mm or more with a grinder or the like, and then measured.
- the component composition is further mass%, Cu: 1.0% or less, Ni: 0.5% or less,
- the rail head is cooled at a cooling start temperature of 800 ° C or higher and a cooling stop temperature of 600 ° C or lower. And a method for manufacturing a rail for cooling at a cooling rate of 1 to 10 ° C./s.
- the component composition is further mass%, Cu: 1.0% or less, Ni: 0.5% or less, The manufacturing method of the rail as described in said (5) containing 1 type (s) or 2 or more types of Mo: 0.5% or less and V: 0.15% or less.
- the said cooling is a manufacturing method of the rail as described in said (5) or (6) which makes the dispersion
- the variation in the hardness in the rail length direction can be extremely reduced, and particularly the durability of the rails laid in a high-axle environment such as heavy cargo railroad or mining railroad (longer life) It is extremely effective for the industry and exerts a large industrial effect.
- C 0.60 to 1.0%
- C is an important element that forms cementite in the pearlite rail to increase hardness and strength and improve wear resistance. However, the effect is small at less than 0.60%, so the lower limit is made 0.60%.
- an increase in the amount of C means an increase in the amount of cementite.
- an increase in hardness and strength can be expected, but the ductility decreases.
- the increase in the amount of C expands the ⁇ + ⁇ temperature range and promotes softening of the weld heat affected zone. Considering these effects, the upper limit of C is set to 1.0%. The preferred range is 0.73 to 0.85%.
- Si 0.1-1.5% Si is added as a deoxidizer in the rail material and to increase the equilibrium transformation temperature (TE) and strengthen the pearlite structure (increased hardness due to the refinement of the lamellar structure). Small effect.
- the increase in Si promotes decarburization and the formation of rail surface defects, so the upper limit was made 1.5%. Preferably, it is in the range of 0.5 to 1.3%.
- Mn 0.01-1.5%
- Mn has the effect of reducing the actual pearlite transformation temperature and densifying the pearlite-lamellar spacing, and is an effective element for achieving high hardness, but the effect is small at less than 0.01%.
- the hardenability is also improved, addition exceeding 1.5% tends to transform into bainite or martensite, so the upper limit was made 1.5%.
- it is in the range of 0.3 to 1.2%.
- the upper limit of P is 0.035%.
- the upper limit is preferably 0.025%.
- the lower limit is preferably 0.001% because special refining or the like causes an increase in melting costs.
- the upper limit of the S content is 0.030%.
- the lower limit is preferably made 0.0005%.
- the content is 0.001 to 0.015%.
- Cr 0.1-2.0% Cr increases the equilibrium transformation temperature (TE) and contributes to the refinement of the pearlite-lamellar spacing, thereby increasing the hardness and strength. For that purpose, addition of 0.2% or more is necessary. On the other hand, addition exceeding 2.0% increases the occurrence of weld defects and increases the hardenability and promotes the formation of martensite, so the upper limit was made 2.0%. More preferably, it is in the range of 0.26 to 1.00%.
- Cu 1.0% or less
- Ni: 0.5% or less, Mo: 0.5% or less, and V: 0.15% or less can be added.
- Cu: 1.0% or less Cu is an element that can achieve higher hardness by solid solution strengthening. It is also effective in suppressing decarburization. In order to obtain this effect, it is preferable to add at 0.01% or more. On the other hand, addition exceeding 1.0% tends to cause surface cracking during continuous casting or rolling, so the upper limit is preferably made 1.0%. Furthermore, the range of 0.05 to 0.6% is even more preferable.
- Ni 0.5% or less
- Ni is an element effective for improving toughness and ductility.
- the lower limit is preferably set to 0.01% or more.
- the upper limit is preferably made 0.5%. More preferably, it is in the range of 0.05 to 0.50%.
- Mo 0.5% or less Mo is an element effective for increasing the strength, and if it is less than 0.01%, the effect is small, so the lower limit is preferably made 0.01%. On the other hand, if added over 0.5%, martensite is generated as a result of increasing hardenability, so the toughness and ductility are extremely reduced. Therefore, the upper limit is preferably 0.5%. More preferably, it is in the range of 0.05 to 0.30%.
- V 0.15% or less
- V is an element that forms VC or VN and precipitates finely in ferrite and contributes to high strength through precipitation strengthening of ferrite.
- the solid solution temperature of VC or VN is sufficiently lower than that of Ti and Nb, and the influence on the recrystallization behavior of austenite at the time of rolling is small, so the influence on the characteristic variation in the rail length direction is also small.
- it functions as a hydrogen trap site and can be expected to suppress delayed fracture.
- it is preferable to add at 0.001% or more.
- the upper limit is preferably made 0.15%. More preferably, it is in the range of 0.005 to 0.12%.
- the balance other than the above components is Fe and inevitable impurities.
- N can be allowed up to 0.006% and O can be allowed up to 0.003%.
- Al is effective as a deoxidizing material, but it is desirable that Al be 0.003% or less in order to form cluster-like AlN and greatly reduce the transfer fatigue characteristics.
- Nb and Ti contained as unavoidable impurities are as follows.
- Nb 0.003% or less
- Ti are elements effective for improving hardness and wear resistance because they form carbides or carbonitrides and strengthen the matrix.
- it is a harmful element that promotes variation in the hardness in the longitudinal direction of the rail, it is basically not added, but the amount inevitably mixed is acceptable if it is 0.003% or less. That is, when Nb or Ti is added, the change in hardness increases according to the material heating, rolling, or cooling conditions, and therefore, it sensitively affects the change in hardness in the rolling length direction due to variations in these conditions.
- the variation in surface hardness in the rail length direction is ⁇ HB15 points or less. This is because if the hardness variation exceeds ⁇ HB15 point, the change in rail wear amount is 20% or more. Furthermore, if the variation in hardness is ⁇ HB10 points or less, the change in the amount of rail wear can be less than 15%. Therefore, the variation in the surface hardness in the rail length direction is more preferably ⁇ HB10 points or less.
- the steel material was obtained by casting the molten steel adjusted to the above component composition by the continuous casting method in the melting process such as blast furnace, hot metal pretreatment, converter, RH degassing, etc. It is desirable to use as a steel material.
- This steel material is formed into a rail shape by hot rolling by ordinary hole rolling or universal rolling. The reasons for limiting the heating and rolling conditions and the subsequent cooling conditions will be described below.
- Heating temperature before hot rolling 1200 °C or higher
- the molten steel material must be heated to 1200 ° C or higher.
- the main purpose is to reduce the rolling load by sufficiently lowering the deformation resistance, but there is another purpose to achieve homogenization.
- the heating temperature needs to be 1200 ° C. or higher.
- the upper limit need not be set in particular, but is preferably 1300 ° C. or less from the viewpoint of suppressing scale loss and decarburization.
- the steel material heated in this way is formed into a rail shape by hot rolling.At that time, by repeating rolling in one direction in rolling of multiple passes performed at 1000 ° C. or less, variation in time between passes of rolling can be achieved. It is important to make it smaller.
- the time between passes in rolling refers to the time from when a portion in the longitudinal direction (rolling direction) of the rolled rail material bites into the roll to bite into the next roll. The difference between the passes is the largest between the top (tip) and the bottom (tail) of the rolled rail material.
- the next pass is the rolling bottom portion ( Since it is the form which sends to a roll in order from a tail end), the time between passes in a rolling top part becomes long.
- the rolling bottom portion (tail end) passes through a certain pass and is first bitten by the roll in the next pass, the time between passes is shortened.
- the difference in the time between passes at the tip and the tail end peculiar to reverse rolling affects the austenite structure state and affects the hardness variation after pearlite transformation.
- the difference in the time between passes between the rolled material tip and the tail end is basically reduced. Therefore, the inhomogeneity of the austenite structure that occurs in accordance with the time difference between the passes is eliminated.
- the time difference between the paths must be within 15 seconds. In other words, if the difference in time between passes is within 15 s, it is possible to suppress variations in hardness in the rail length direction. Preferably, it is within 12 s.
- the above rules are conditions applied to rolling performed at 1000 ° C. or less in hot rolling, and reverse rolling may be used for rolling in a temperature range exceeding 1000 ° C. represented by the rough rolling step.
- rolling at 1000 ° C. or lower can be performed continuously in one direction, rolling in a temperature region exceeding 1000 ° C. in the preceding stage is optional.
- the hot rolling at 1000 ° C. or lower is preferably performed in 2 to 7 passes. This is because, in 1-pass rolling, the rolling load becomes large and shaping is difficult, and conversely, if it exceeds 7 passes, the austenite state is somewhat non-uniform and hardness variation tends to increase.
- [Cumulative area reduction of the rail head is 40% or more] It is necessary to reduce the area reduction rate by rolling below 1000 ° C to 40% or more. This is because, in order to promote recrystallization refinement of austenite, a surface reduction process of 40% or more is required at 1000 ° C. or lower. If the reduction in area is less than 40% when rolling at 1000 ° C or less, the recrystallization refinement of austenite becomes insufficient, resulting in partially coarse austenite remaining, resulting in the rail length direction (rolling direction). This will increase the hardness variation.
- the finish rolling temperature is desirably 900 ° C. or higher. This is because if the finish rolling temperature falls below 900 ° C., the cooling start temperature of the on-line heat treatment that is subsequently performed after rolling is lowered, and the pearlite transformation is promoted (increased). This is because the thickness decreases and the variation increases. In order to prevent such a decrease in hardness, the finish rolling temperature is preferably 900 ° C. or higher.
- the rail head is cooled at a cooling start temperature of 800 ° C or higher, a cooling stop temperature of 600 ° C or lower, and a cooling rate of 1 to 10 ° C / s.”
- the cooling start temperature is desirably 800 ° C. or higher. That is, if the cooling start temperature is less than 800 ° C., the degree of supercooling may not be sufficiently ensured and sufficient surface hardness may not be obtained.
- the cooling stop temperature must be 600 ° C or less. This is because sufficient hardness cannot be obtained at 600 ° C. or higher.
- the lower limit is not specified in particular, but the hardness is saturated even if it is cooled to 400 ° C or lower, and in addition, the cooling time is prolonged, so the productivity is hindered. desirable.
- the cooling rate is in the range of 1-10 ° C./s. When the cooling rate exceeds 10 ° C / s, sufficient time for pearlite transformation cannot be ensured, and bainite and martensite are formed, reducing toughness and fatigue damage. On the other hand, if it is less than 1 ° C./s, sufficient hardness cannot be obtained. Preferably, it is in the range of 2 to 8 ° C./s. Furthermore, it is preferable that the variation in the cooling rate in the rolling longitudinal direction is ⁇ 1 ° C./s or less.
- the cooling performed subsequent to the hot rolling is preferably blast cooling or mist cooling.
- blast cooling is to perform accelerated cooling by forcing air to the rail head.
- mist cooling is mixing water and air, making water mist-like, and spraying on a rail head part.
- the air pressure is controlled at intervals of 5 m or less (preferably 3 m or less), and the rails measured before cooling are controlled. It is necessary to adjust the air pressure according to the temperature variation in the longitudinal direction on-line and to control the cooling rate to be constant in the length direction. Similarly, in the case of mist cooling, it is desirable to cool by controlling the amount of water and pressure in the longitudinal direction.
- the surface hardness in the rail length direction is preferably HB400 or more, the variation is ⁇ HB15 points or less, and the hardness variation in the rolling length direction is small and uniform. High hardness pearlite steel rail can be obtained.
- a steel having a chemical composition shown in Table 1 was melted, and a slab obtained by continuous casting was heated, hot-rolled, and cooled to produce a 136 lb or 141 lb rail.
- the manufacturing conditions and the investigation results of the surface hardness and its variation are also shown in Table 2.
- the variation in the time between passes in the rolling conditions is the time from when the tip of the rolled material is rolled to the next rolling and the time from when the tail end of the rolled material is rolled to the next rolling.
- the difference in the time between passes at the rolling top portion becomes longer, while the time between passes at the rolling bottom portion becomes shorter.
- the difference in the time between passes at the front end (top portion) and the tail end (bottom portion) of the rolled material is significant in reverse rolling.
- the difference in time between passes associated with the tip and tail ends of the rolled material is reduced, so that the inhomogeneity of the generated structure can be eliminated as shown in Table 2. It is.
- the cooling start temperature and stop temperature are the results of measuring the surface temperature of the rail corner portion with a thermoviewer.
- the cooling rate was measured and averaged from the cooling start, cooling stop temperature, and cooling time measured at a pitch of 5 m in the length direction.
- the difference between the maximum value and the minimum value of the variation in individual cooling rates was more than ⁇ 1 ° C./s or less than ⁇ 1 ° C./s.
- the surface hardness and microstructure of the head of the manufactured rail were evaluated.
- the decarburized layer was removed by 0.5 mm or more with a grinder, and the Brinell hardness was measured at points of 5 m pitch in the rail length direction. Similarly, a microscope sample was cut out and the microstructure was observed. These evaluation results are shown in Table 2.
- the rail according to the present invention has a very small variation in hardness in the length direction of ⁇ HB15 or less, whereas a rail whose component composition or rolling condition deviates from the scope of the present invention has a variation in hardness. It exceeded ⁇ HB15.
Abstract
Description
例えば、特許文献1、特許文献2、特許文献3および特許文献4には、セメンタイトの量を増加させた過共析レールおよびその製造方法について開示されている。さらに、特許文献5、特許文献6および特許文献7には、共析炭素レベルの鋼に対してパーライト組織のラメラー間隔を微細化することによって高硬度化を図った技術が開示されている。
なお、摩耗試験は、短時間で耐摩耗性を評価することができる西原式摩耗試験機を用いて実際のパーライト鋼レールと車輪との接触条件をシミュレートした比較試験とした。すなわち、図2に示すように、レール頭部から採取した、外径30mmの西原式摩耗試験片1をタイヤ試験片2と接触させて回転させて試験を行う。同図中の矢印は、それぞれ西原式摩耗試験片1とタイヤ試験片2の回転方向を示す。タイヤ試験片は、JIS規格E1101に記載の普通レールの頭部から直径32mmの丸棒を採取し、ブリネル硬さ(Brinell荷重29.4kN)がHB370であり、組織が焼戻しマルテンサイト組織となるように熱処理を行い、その後、 図2に示す形状に加工を施し、タイヤ試験片とした。なお、西原式摩耗試験片1は、図3に示すようにレール頭部3の2箇所から採取する。レール頭部3の表層から採取するものを西原式摩耗試験片1aとし、内部から採取するものを西原式摩耗試験片1bとする。レール頭部3の内部から採取する西原式摩耗試験片1b の長手方向の中心は、レール頭部3の上面から24~26mm(平均値25mm)の深さに位置する。試験環境条件は乾燥状態とし、接触圧力:1.2GPa, 滑り率:-10%,回転速度: 750rpm(タイヤ試験片は750rpm)の条件で1.8×105回転後の摩耗量を測定する。摩耗量は、試験前後の試験片重量を測定し、その差によって算出した。
(1)質量%で、
C:0.60~1.0%、
Si:0.1~1.5%、
Mn:0.01~1.5%、
P:0.035%以下、
S:0.030%以下および
Cr:0.1~2.0%
を含有し、残部がFeおよび不可避的不純物の成分組成を有するレールであって、該レール長さ方向のレール頭部の表面硬さのばらつきが±HB15ポイント以下であるレール。
ここで、レール長さ方向の表面硬さのばらつきは、レール頭頂部を圧延長さ方向に5mピッチでレール全長(例えば25~100m)にわたってブリネル硬さを測定し、測定結果から算出した平均値と、各測定点でのブリネル硬さの値との差のことを意味する。すなわち、レールの長さ方向の表面硬さのばらつきが±HB15ポイント以下とは、5mピッチで測定した全ての硬さの測定値(全長25mの場合は6点、全長50mの場合は11点、全長100mの場合は21点についての測定値)からブリネル硬さの平均値を求め、その平均値と各測定点についてのブリネル硬さとの差が最大で±15ポイント以内であることを意味する。なお、ブリネル硬さの測定に際しては、脱炭層をグラインダなどで予め0.5mm以上除去した後に、測定を行う。
Cu:1.0%以下、
Ni:0.5%以下、
Mo:0.5%以下および
V:0.15%以下
の1種または2種以上を含有する前記(1)に記載のレール。
C:0.60~1.0%、
Si:0.1~1.5%、
Mn:0.01~1.5%、
P:0.035%以下、
S:0.030%以下および
Cr:0.1~2.0%
を含有し、残部がFeおよび不可避的不純物の成分組成になる鋼素材を、1200℃以上に加熱した後、熱間圧延を施してレールを製造するに当たって、
前記熱間圧延において、1000℃以下の温度域にてレール長さ方向へ複数パスにわたる圧延を行い、該圧延を行う際の、レール長さ方向のパス間時間のばらつきを15s以内、レール頭部となる部分の累積減面率を40%以上、仕上げ圧延温度を900℃以上とし、該熱間圧延に引き続いて、レール頭部に、冷却開始温度:800℃以上、冷却停止温度:600℃以下および冷却速度:1~10℃/sとした冷却を行うレールの製造方法。
Cu:1.0%以下、
Ni:0.5%以下、
Mo:0.5%以下および
V:0.15%以下
の1種または2種以上を含有する前記(5)に記載のレールの製造方法。
C:0.60~1.0%
Cは、パーライトレールにおいてセメンタイトを形成し硬さや強度を高め、耐摩耗性を向上させる重要な元素である。しかし、0.60%未満ではそれらの効果が小さいことから、下限を0.60%とする。一方、C量の増加はセメンタイト量の増加を意味しており、硬さや強度の上昇が期待できる反面延性は低下することになる。また、C量の増加はγ+θ温度範囲を拡大させ、溶接熱影響部の軟化を助長する。これらの影響を考慮してCの上限は1.0%とする。好ましい範囲は、0.73~0.85%である。
Siは、レール材における脱酸材として、および平衡変態温度(TE)を上昇させてパーライト組織を強化(ラメラー組織の微細化による硬さ上昇)するために添加するが、0.1%未満ではこれらの効果が小さい。一方、Siの増加は脱炭を促進させることや、レールの表面疵の生成を促進させることから、上限を1.5%とした。好ましくは、0.5~1.3%の範囲である。
Mnは、実際のパーライト変態温度を低下させてパーライト-ラメラー間隔を緻密にする効果があり、高硬度とするために有効な元素であるが、0.01%未満ではその効果が小さい。一方、焼入れ性も向上させることから1.5%を超えての添加は、ベイナイトやマルテンサイトへ変態し易くなるため、上限を1.5%とした。好ましくは、0.3~1.2%の範囲である。
Pは0.035%を超えると、靭性や延性を低下させる。そのため、Pの上限は0.035%とする。好適範囲としては0.025%を上限とする。一方、下限については、特殊精錬などを行うと溶製のコスト上昇を招くことから0.001%とすることが好ましい。
Sは、圧延方向に伸展した粗大なMnSを形成して、延性や靭性を低下させる。そのため、Sの含有量の上限は0.030%とした。一方、0.0005%未満にするためには、溶製処理時間の増大など溶製時のコスト上昇が著しいため、下限は0.0005%とすることが好ましい。好ましくは、0.001~0.015%である。
Crは、平衡変態温度(TE)を上昇させ、パーライト-ラメラー間隔の微細化に寄与して、硬さや強度を上昇させる。そのためには、0.2%以上の添加を必要 とする。一方、2.0%を超えての添加は、溶接欠陥の発生を増加させるとともに、焼入れ性を増加させマルテンサイトの生成を促進させるため、上限を 2.0%とした。より好ましくは、0.26~1.00%の範囲である。
Cu:1.0%以下
Cuは、固溶強化により一層の高硬度化を図ることができる元素である。また、脱炭抑制にも効果がある。この効果を得るためには0.01%以上で添加することが好ましい。一方、1.0%を超えての添加は連続鋳造時や圧延時に表面割れを生じ易くすることから、上限を1.0%とすることが好ましい。さらに、0.05~0.6%の範囲がより一層好ましい。
Niは、靭性や延性を向上させるのに有効な元素である。また、Cuと複合添加することでCu割れを抑制するのに有効な元素であるため、Cuを添加する場合にはNiを添加することが望ましい。但し、0.01%未満ではこれら効果が認められないことから、添加する場合には下限を0.01%以上とすることが好ましい。一方、0.5%を超えての添加は、焼入れ性を高めマルテンサイトの生成を促進させることになるため、上限を0.5%とすることが好ましい。より好ましくは、0.05~0.50%の範囲である。
Moは、高強度化に有効な元素であり、0.01%未満ではその効果が小さいため、下限を0.01%とすることが好ましい。一方、0.5%を超えて添加すると、焼入れ性が高まる結果としてマルテンサイトが生成するため、靭性や延性を極端に低下させる。そのため、上限は0.5%とすることが好ましい。より好ましくは、0.05~0.30%の範囲である。
Vは、VCあるいはVNなどを形成してフェライト中へ微細に析出し、フェライトの析出強化を通して高強度化に寄与する元素である。また、VCあるいはVN の固溶温度は、TiやNbよりも十分低く、圧延時のオーステナイトの再結晶挙動に及ぼす影響も小さいため、レール長さ方向の特性ばらつきに与える影響も小さい。さらに、水素のトラップサイトとしても機能し、遅れ破壊を抑制する効果も期待できる。そのためには、0.001%以上で添加することが好ましい。一方、0.15%を超えて添加すると、上記の諸効果が飽和し合金コストの上昇も甚だしいことから、上限は0.15%とすることが好ましい。より好適には、0.005~0.12%の範囲である。
例えば、不可避的不純物として、Nは0.006%まで、Oは0.003%まで許容できる。また、Alは脱酸材として有効であるが、クラスター状のAlNを形成し転勤疲労特性を大きく低下させるため、Alについては0.003%以下とすることが望ましい。さらに、不可避的不純物として含まれる、NbおよびTiについては、次のとおりである。
Ti:0.003%以下
NbおよびTiは、炭化物あるいは炭窒化物を形成しマトリクスを強化することから、硬さや耐摩耗性の向上に対して有効な元素である。しかしながら、レール長手方向の硬さのばらつきを促進させる有害な元素であることから基本的には無添加とするが、不可避的に混入する量としては0.003%以下であれば許容できる。すなわち、NbやTiを添加すると、素材加熱、圧延あるいは冷却条件に応じて硬さの変化が大きくなるため、これら条件のばらつきに伴う圧延 長さ方向の硬さ変化に敏感に影響を与える。冶金的には、加熱オーステナイト粒の不均一性が促進されると同時に、圧延中のオーステナイトの再結晶化の抑制とそれに伴うパーライト変態温度の変化が、NbやTiが無添加の鋼よりも極めて大きくなるため、硬さのばらつきを促進させていると考えられる。
まず、鋼素材には、高炉、溶銑予備処理、転炉、RH脱ガスなどの溶製法プロセスにて、上記した成分組成に調整された溶鋼を連続鋳造法にて鋳造して得た、鋳片を鋼素材として用いることが望ましい。
溶製された鋼素材は、1200℃以上に加熱する必要がある。ここでは、十分に変形抵抗を下げることで圧延負荷の軽減を図ることが主目的であるが、そのほか、均質化を図る目的もある。これらの効果を十分に得るには、加熱温度を1200℃以上とする必要がある。なお、上限は特に設定する必要はないが、スケールロスや脱炭の抑制の観点から1300℃以下とすることが好ましい。
こうして加熱された鋼素材は、熱間圧延によりレール形状へと成形するが、その際、1000℃以下で行う複数パスの圧延において一方向の圧延を繰り返すことによって、圧延のパス間時間のばらつきを小さくすることが肝要である。なお、圧延におけるパス間時間とは、レール圧延材の長手方向(圧延方向)のある部分がロールに噛み込んでから次のロールに噛み込むまでの時間のことを言う。そして、このパス間時間は、レール圧延材のトップ(先端)におけるものとボトム(尾端)におけるものとで最も差が大きくなる。
1000℃以下での圧延による減面率を累積で40%以上とする必要がある。なぜなら、オーステナイトの再結晶細粒化を促すためには1000℃以下で40%以上の減面加工が必要となるからである。1000℃以下の圧延での減面率が40%未満の場合には、オーステナイトの再結晶細粒化が不十分となり、部分的に粗大なオーステナイトが残存する結果、レール長さ方向(圧延方向)の硬さばらつきを増加させることになる。
一方向へ連続圧延を行うことによって、圧延材全長のパス間時間のばらつきを小さくするに当たって、仕上げ圧延温度は900℃以上とすることが望ましい。なぜなら、仕上げ圧延温度が900℃を下回ると、圧延後に引き続き実行されるオンライン熱処理の冷却開始温度が低温化すること、パーライト変態が促進する(高温化する)ことなどの理由により、全体的に硬さが低下しばらつきが大きくなるためである。こうした硬さ低下を防止するためには、仕上げ圧延温度を900℃以上とすることが好ましい。
「レール頭部に冷却開始温度:800℃以上、冷却停止温度:600℃以下、冷却速度:1~10℃/sとした冷却を行う」
まず、冷却開始温度は、800℃以上が望ましい。すなわち、冷却開始温度が800℃未満では過冷度が十分に確保されずに十分な表面硬さを得ることができないおそれがある。冷却停止温度は600℃以下まで行う必要がある。600℃以上では十分な硬さを得ることができないためである。下限については特に規定しないが、400℃以下まで冷却しても硬さが飽和すること、加えて冷却時間が長くなるために生産性を阻害することから、400℃以上で冷却を停止することが望ましい。
冷却速度は1~10℃/sの範囲である。冷却速度が10℃/sを超えるとパーライト変態する時間が十分確保できず、ベイナイトやマルテンサイトが生成し、靱延性や疲労損傷性を低下させる。一方、1℃/s未満では十分な硬さを得ることはできない。好ましくは、2~8℃/sの範囲である。
さらに、圧延長手方向での冷却速度のばらつきを±1℃/s以下にすることが好ましい。冷却速度のばらつきを±1℃/s以下とすることで、パーライト-ラメラー間隔のばらつきがより小さくなり、硬さのばらつき±HB10以下を達成でき、レール長手方向で耐摩耗性や耐疲労損傷性にばらつきがより小さくなるためである。
また、上記の熱間圧延に引き続いて行う冷却は、衝風冷却あるいはミスト冷却を行うことが好ましい。ここで、衝風冷却とは、エアーを強制的にレール頭部に吹き付けることで加速冷却を行うことである。また、ミスト冷却とは、水とエアーとを混合して水を霧状にしてレール頭部に吹き付けることである。
さらに、製造されたレールについて、その頭部の表面硬さおよびミクロ組織を評価した。レール頭部表面の硬さについては、脱炭層を0.5mm以上グラインダにて除去し、レール長さ方向に5mピッチの点において、それぞれブリネル硬さを測定した。同様に顕微鏡サンプルを切り出し、ミクロ組織を観察した。
これらの評価結果を表2に示す。
Claims (7)
- 質量%で、
C:0.60~1.0%、
Si:0.1~1.5%、
Mn:0.01~1.5%、
P:0.035%以下、
S:0.030%以下および
Cr:0.1~2.0%
を含有し、残部がFeおよび不可避的不純物の成分組成を有するレールであって、該レール長さ方向のレール頭部の表面硬さのばらつきが±HB15ポイント以下であるレール。 - 前記成分組成はさらに、質量%で、
Cu:1.0%以下、
Ni:0.5%以下、
Mo:0.5%以下および
V:0.15%以下
の1種または2種以上を含有する請求項1に記載のレール。 - 前記レール頭部の表面硬さがHB400以上である請求項1または2に記載のレール。
- 前記表面硬さのばらつきが±HB10ポイント以下である請求項1乃至3のいずれかに記載のレール。
- C:0.60~1.0%、
Si:0.1~1.5%、
Mn:0.01~1.5%、
P:0.035%以下、
S:0.030%以下および
Cr:0.1~2.0%
を含有し、残部がFeおよび不可避的不純物の成分組成になる鋼素材を、1200℃以上に加熱した後、熱間圧延を施してレールを製造するに当たって、
前記熱間圧延において、1000℃以下の温度域にてレール長さ方向へ複数パスにわたる圧延を行い、該圧延を行う際の、レール長さ方向のパス間時間のばらつきを15s以内、レール頭部となる部分の累積減面率を40%以上、仕上げ圧延温度を900℃以上とし、該熱間圧延に引き続いて、レール頭部に、冷却開始温度:800℃以上、冷却停止温度:600℃以下および冷却速度:1~10℃/sとした冷却を行うレールの製造方法。 - 前記成分組成はさらに、質量%で、
Cu:1.0%以下、
Ni:0.5%以下、
Mo:0.5%以下および
V:0.15%以下
の1種または2種以上を含有する請求項5に記載のレールの製造方法。 - 前記冷却は、レールの長さ方向の冷却速度のばらつきを±1℃/s以下とする請求項5または6に記載のレールの製造方法。
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP15768893.8A EP3124636B2 (en) | 2014-03-24 | 2015-03-24 | Rail and method for manufacturing same |
JP2016510035A JP6150008B2 (ja) | 2014-03-24 | 2015-03-24 | レールおよびその製造方法 |
CA2936780A CA2936780C (en) | 2014-03-24 | 2015-03-24 | Rail and method for manufacturing same |
CN201580013144.3A CN106103772B (zh) | 2014-03-24 | 2015-03-24 | 钢轨及其制造方法 |
US15/128,267 US20170101692A1 (en) | 2014-03-24 | 2015-03-24 | Rail and method for manufacturing same |
AU2015237464A AU2015237464B2 (en) | 2014-03-24 | 2015-03-24 | Rail and method for manufacturing same |
BR112016022007-2A BR112016022007B1 (pt) | 2014-03-24 | 2015-03-24 | trilho e método de fabricação do mesmo |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2014-060786 | 2014-03-24 | ||
JP2014060786 | 2014-03-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2015146150A1 true WO2015146150A1 (ja) | 2015-10-01 |
Family
ID=54194697
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2015/001659 WO2015146150A1 (ja) | 2014-03-24 | 2015-03-24 | レールおよびその製造方法 |
Country Status (8)
Country | Link |
---|---|
US (1) | US20170101692A1 (ja) |
EP (1) | EP3124636B2 (ja) |
JP (1) | JP6150008B2 (ja) |
CN (1) | CN106103772B (ja) |
AU (1) | AU2015237464B2 (ja) |
BR (1) | BR112016022007B1 (ja) |
CA (1) | CA2936780C (ja) |
WO (1) | WO2015146150A1 (ja) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107326302A (zh) * | 2017-05-26 | 2017-11-07 | 北京交通大学 | 一种耐蚀贝氏体钢、钢轨及制备方法 |
WO2019189688A1 (ja) * | 2018-03-30 | 2019-10-03 | Jfeスチール株式会社 | レールおよびその製造方法 |
WO2019189686A1 (ja) * | 2018-03-30 | 2019-10-03 | Jfeスチール株式会社 | レールおよびその製造方法 |
JP2020070495A (ja) * | 2018-10-26 | 2020-05-07 | Jfeスチール株式会社 | レールおよびその製造方法 |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6150008B2 (ja) | 2014-03-24 | 2017-06-21 | Jfeスチール株式会社 | レールおよびその製造方法 |
US10233512B2 (en) * | 2014-05-29 | 2019-03-19 | Nippon Steel & Sumitomo Metal Corporation | Rail and production method therefor |
CN106636891A (zh) * | 2016-11-17 | 2017-05-10 | 马鞍山市银鼎机械制造有限公司 | 抗震铁路钢轨用球磨铸铁制备方法 |
WO2019102258A1 (en) * | 2017-11-27 | 2019-05-31 | Arcelormittal | Method for manufacturing a rail and corresponding rail |
WO2019189015A1 (ja) | 2018-03-30 | 2019-10-03 | Jfeスチール株式会社 | レール |
SE543919C2 (en) * | 2019-05-17 | 2021-09-21 | Husqvarna Ab | Steel for a sawing device |
CN112575137B (zh) * | 2020-10-26 | 2022-03-25 | 邯郸钢铁集团有限责任公司 | 一种高速轨钢转炉冶炼直接出钢的方法 |
EP4247987A1 (en) * | 2020-11-17 | 2023-09-27 | ArcelorMittal | Steel for rails and a method of manufacturing of a rail thereof |
CN114058824B (zh) * | 2021-11-26 | 2023-12-08 | 武汉钢铁有限公司 | 一种提高热处理钢轨踏面硬度均匀性的生产方法及所得钢轨 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01104721A (ja) * | 1987-10-19 | 1989-04-21 | Nippon Steel Corp | 高温レールの冷却法 |
JPH01104720A (ja) * | 1987-10-19 | 1989-04-21 | Nippon Steel Corp | 高温レールの冷却法 |
JP2008050687A (ja) * | 2006-07-24 | 2008-03-06 | Nippon Steel Corp | 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 |
JP2010077481A (ja) * | 2008-09-25 | 2010-04-08 | Jfe Steel Corp | 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 |
JP2010185106A (ja) * | 2009-02-12 | 2010-08-26 | Jfe Steel Corp | 耐摩耗性レールおよびその製造方法 |
Family Cites Families (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2773867A (en) * | 1954-05-17 | 1956-12-11 | Glidden Co | Process for dehalogenating steroids |
JPS6289818A (ja) * | 1985-10-14 | 1987-04-24 | Nippon Kokan Kk <Nkk> | レ−ルの熱処理方法 |
US4886558A (en) † | 1987-05-28 | 1989-12-12 | Nkk Corporation | Method for heat-treating steel rail head |
RU2107740C1 (ru) † | 1993-12-20 | 1998-03-27 | Ниппон Стил Корпорейшн | Рельс из перлитной стали с высокой износостойкостью и ударной вязкостью и способ его производства |
JPH07216454A (ja) † | 1994-01-31 | 1995-08-15 | Nippon Steel Corp | レールの熱処理方法 |
US6804795B1 (en) * | 1999-04-02 | 2004-10-12 | Sony Corporation | Electronic device and its repairing method |
JP2001234238A (ja) * | 2000-02-18 | 2001-08-28 | Nippon Steel Corp | 高耐摩耗・高靭性レールの製造方法 |
WO2003085149A1 (fr) * | 2002-04-05 | 2003-10-16 | Nippon Steel Corporation | Rail a base de perlite ayant une excellente resistance a l'usure et une excellente ductilite et procede de production de ce rail |
US7288159B2 (en) | 2002-04-10 | 2007-10-30 | Cf&I Steel, L.P. | High impact and wear resistant steel |
CN1754973A (zh) | 2004-09-27 | 2006-04-05 | 铁道科学研究院 | 含Cr热处理轨钢 |
CA2679556C (en) * | 2007-03-28 | 2013-05-28 | Jfe Steel Corporation | Internal high hardness type pearlitic rail with excellent wear resistance and rolling contact fatigue resistance and method for producing same |
CA2734980C (en) * | 2008-10-31 | 2014-10-21 | Nippon Steel Corporation | Pearlite rail having superior abrasion resistance and excellent toughness |
US8469284B2 (en) * | 2009-02-18 | 2013-06-25 | Nippon Steel & Sumitomo Metal Corporation | Pearlitic rail with excellent wear resistance and toughness |
CN102220545B (zh) * | 2010-04-16 | 2013-02-27 | 攀钢集团有限公司 | 耐磨性和塑性优良的高碳高强热处理钢轨及其制造方法 |
JP5438219B2 (ja) | 2010-07-15 | 2014-03-12 | 京セラ株式会社 | 無線通信システム、移動局、基地局及び無線通信方法 |
JP6150008B2 (ja) | 2014-03-24 | 2017-06-21 | Jfeスチール株式会社 | レールおよびその製造方法 |
-
2015
- 2015-03-24 JP JP2016510035A patent/JP6150008B2/ja active Active
- 2015-03-24 CA CA2936780A patent/CA2936780C/en active Active
- 2015-03-24 BR BR112016022007-2A patent/BR112016022007B1/pt active IP Right Grant
- 2015-03-24 AU AU2015237464A patent/AU2015237464B2/en active Active
- 2015-03-24 WO PCT/JP2015/001659 patent/WO2015146150A1/ja active Application Filing
- 2015-03-24 CN CN201580013144.3A patent/CN106103772B/zh active Active
- 2015-03-24 US US15/128,267 patent/US20170101692A1/en not_active Abandoned
- 2015-03-24 EP EP15768893.8A patent/EP3124636B2/en active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01104721A (ja) * | 1987-10-19 | 1989-04-21 | Nippon Steel Corp | 高温レールの冷却法 |
JPH01104720A (ja) * | 1987-10-19 | 1989-04-21 | Nippon Steel Corp | 高温レールの冷却法 |
JP2008050687A (ja) * | 2006-07-24 | 2008-03-06 | Nippon Steel Corp | 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 |
JP2010077481A (ja) * | 2008-09-25 | 2010-04-08 | Jfe Steel Corp | 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 |
JP2010185106A (ja) * | 2009-02-12 | 2010-08-26 | Jfe Steel Corp | 耐摩耗性レールおよびその製造方法 |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107326302A (zh) * | 2017-05-26 | 2017-11-07 | 北京交通大学 | 一种耐蚀贝氏体钢、钢轨及制备方法 |
CN107326302B (zh) * | 2017-05-26 | 2018-10-19 | 北京交通大学 | 一种耐蚀贝氏体钢、钢轨及制备方法 |
WO2019189688A1 (ja) * | 2018-03-30 | 2019-10-03 | Jfeスチール株式会社 | レールおよびその製造方法 |
WO2019189686A1 (ja) * | 2018-03-30 | 2019-10-03 | Jfeスチール株式会社 | レールおよびその製造方法 |
JPWO2019189688A1 (ja) * | 2018-03-30 | 2020-04-30 | Jfeスチール株式会社 | レールおよびその製造方法 |
JPWO2019189686A1 (ja) * | 2018-03-30 | 2020-08-06 | Jfeスチール株式会社 | レールおよびその製造方法 |
CN111918980A (zh) * | 2018-03-30 | 2020-11-10 | 杰富意钢铁株式会社 | 导轨及其制造方法 |
US11492689B2 (en) | 2018-03-30 | 2022-11-08 | Jfe Steel Corporation | Rail and method for manufacturing same |
US11530471B2 (en) | 2018-03-30 | 2022-12-20 | Jfe Steel Corporation | Rail and method for manufacturing same |
JP2020070495A (ja) * | 2018-10-26 | 2020-05-07 | Jfeスチール株式会社 | レールおよびその製造方法 |
Also Published As
Publication number | Publication date |
---|---|
CA2936780A1 (en) | 2015-10-01 |
US20170101692A1 (en) | 2017-04-13 |
CA2936780C (en) | 2018-10-02 |
CN106103772B (zh) | 2018-05-22 |
CN106103772A (zh) | 2016-11-09 |
EP3124636B2 (en) | 2023-05-17 |
JPWO2015146150A1 (ja) | 2017-04-13 |
BR112016022007B1 (pt) | 2021-05-11 |
AU2015237464A1 (en) | 2016-08-11 |
JP6150008B2 (ja) | 2017-06-21 |
EP3124636A4 (en) | 2017-02-01 |
EP3124636A1 (en) | 2017-02-01 |
EP3124636B1 (en) | 2019-03-06 |
AU2015237464B2 (en) | 2018-02-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6150008B2 (ja) | レールおよびその製造方法 | |
US20190338402A1 (en) | Method for manufacturing railway vehicle wheel | |
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 | |
US9840759B2 (en) | Rolled round steel material for steering rack bar and steering rack bar | |
EP3015561B1 (en) | Abrasion-resistant steel material excellent in fatigue characteristics and method for manufacturing same | |
JP6769579B2 (ja) | レールおよびその製造方法 | |
CN112689541B (zh) | 制造具有改善的耐磨性和接触强度的铁路轨道的方法 | |
CN113966406B (zh) | 钢轨及其制造方法 | |
JP6852761B2 (ja) | レールおよびその製造方法 | |
RU2601847C1 (ru) | Способ изготовления рельсов низкотемпературной надежности | |
JP6137043B2 (ja) | レールの製造方法 | |
JP2014084507A (ja) | レール | |
CN113557312A (zh) | 钢轨 | |
JP6822575B2 (ja) | レールおよびその製造方法 | |
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 | |
JPWO2021070452A1 (ja) | レール及びその製造方法 | |
JPH06336613A (ja) | 耐表面損傷性に優れた高強度ベイナイト系レールの製造法 | |
JPH06279925A (ja) | 耐ころがり疲労損傷性に優れた高強度レールおよびその製造法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 15768893 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2016510035 Country of ref document: JP Kind code of ref document: A |
|
ENP | Entry into the national phase |
Ref document number: 2936780 Country of ref document: CA |
|
REEP | Request for entry into the european phase |
Ref document number: 2015768893 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2015768893 Country of ref document: EP |
|
ENP | Entry into the national phase |
Ref document number: 2015237464 Country of ref document: AU Date of ref document: 20150324 Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 15128267 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
REG | Reference to national code |
Ref country code: BR Ref legal event code: B01A Ref document number: 112016022007 Country of ref document: BR |
|
ENP | Entry into the national phase |
Ref document number: 112016022007 Country of ref document: BR Kind code of ref document: A2 Effective date: 20160923 |