A kind of railroad frog High wear-resistant steel and its manufacture method
Technical field
The invention belongs to steel alloy and its method field of manufacturing, it is related to a kind of high performance steel alloy, more particularly to one
Kind of railroad frog highly wear-resisting alloy steel and its manufacture method, described steel alloy have strength character very high and excellent resistance to
Mill performance, while having toughness index very high, and with inherent quality stabilization and uniform advantage, is particularly well-suited at a high speed
Heavy haul railway railway frog.
Background technology
High-speed overload railway is constituted extremely tight with the comfortable property of its big axle weight, high density and large conveying quantity to track switch equipment
Cruel service condition, makes the abrasion of the part such as railway frog and hurt in track switch be far longer than common line same model track switch.With iron
Road is transported to heavily loaded further development, and the high manganese steel frog of active service has been increasingly difficult to meet its demand.For service condition
Severe railway frog (especially central body of frog and wing rail), not only needs enough hardness and intensity, and also need to enough
Toughness is to improve its wearability, while needing the whole railway frog section to have the uniformity consistency of performance and the stabilization of inherent quality
Property.
Therefore, recently during the last ten years, the high resistance to of high-speed overload railway transportation requirement all is met trying hard to develop both at home and abroad
Mill property alloy steel frog.For example, CN100449027C discloses a kind of abrasion-resistant stee suitable for railway switch, using Si-Mn-
Alloying element based on Cr-Mo simultaneously adds V, Ti crystal grain thinning, and manufacture employs thermomechanical treatment process and carries to a certain extent
The quality stability of railway frog high and production cost is reduced, but its hardness and impact flexibility are not very superior.
CN1166804C discloses the special superpower weldable air-cooled great health bainitic steel of high-ductility of railroad frog and its manufacture method, and it is used
With Mn, Si as main alloy element, it is aided with the elements such as Cr, Ni, Mo, and is crystal grain thinning element with Ti, V, Nb, manufacture is employed
Common smelting mode, but due to using Mn, Si for main adding elements, inevitably occur Mn in smelting process
Segregation, so as to cause the less stable of the uneven and inherent quality of section performance, simultaneously because the larger addition of Si, makes
Into a large amount of oxidations of the workpiece surface in forging and heat treatment process, so as to waste material and increased processing charges.
The content of the invention
It is polynary by Mn, Cr, Ni, Mo etc. it is an object of the invention to provide a kind of railroad frog highly wear-resisting alloy steel
Compound adding technique, and it is aided with Al, Nb crystal grain thinning, to obtain the abrasion-resistant stee of a kind of high intensity, high rigidity, high tenacity, especially
Suitable for high-speed overload railroad frog.
Another object of the present invention is also resided in and provides a kind of manufacture method of the steel alloy, at smelting, forging, heat
Reason system control technique, described manufacture method can guarantee that the stability and uniformity of steel alloy internal performance quality of the present invention.
The purpose of the present invention is achieved through the following technical solutions, a kind of railroad frog highly wear-resisting alloy steel, respectively
Component and its mass percent are as follows:C 0.29%~0.45%, Si 0.20%~0.59%, Mn 0.90%~1.51%, P
≤ 0.015%, S≤0.010%, Cr 1.52%~1.79%, Ni 1.01%~1.49%, Mo 0.29%~0.59%, Al
0.02%~0.07%, Nb 0.025%~0.10%, 0.05%≤Nb+Al≤0.15%, [O]≤20ppm, [N]≤
100ppm, [H]≤0.50ppm, balance of iron and other inevitable impurity.
Prioritization scheme of the invention, its each component and its mass percent are as follows:
(1) C 0.29%~0.34%, Si 0.20%~0.59%, Mn 1.01%~1.51%, P≤0.015%, S
≤ 0.010%, Cr 1.52%~1.79%, Ni 1.21%~1.49%, Mo 0.35%~0.59%, Al 0.02%~
0.07%th, Nb 0.025%~0.10%, 0.05%≤Nb+Al≤0.15%, [O]≤20ppm, [N]≤100ppm, [H]≤
0.50ppm, balance of iron and other inevitable impurity.
(2) C 0.35%~0.39%, Si 0.20%~0.59%, Mn 0.90%~1.51%, P≤0.015%, S
≤ 0.010%, Cr 1.52%~1.79%, Ni 1.01%~1.49%, Mo 0.29%~0.59%, Al 0.02%~
0.07%th, Nb 0.025%~0.10%, 0.05%≤Nb+Al≤0.15%, [O]≤20ppm, [N]≤100ppm, [H]≤
0.50ppm, balance of iron and other inevitable impurity.
(3) C 0.40%~0.45%, Si 0.20%~0.59%, Mn 0.90%~1.51%, P≤0.015%, S
≤ 0.010%, Cr 1.52%~1.79%, Ni 1.01%~1.31%, Mo 0.29%~0.49%, Al 0.02%~
0.07%th, Nb 0.025%~0.10%, 0.05%≤Nb+Al≤0.15%, [O]≤20ppm, [N]≤100ppm, [H]≤
0.50ppm, balance of iron and other inevitable impurity.
The phosphorus content of wear-resisting alloy steel of the invention is 0.29%~0.45%, to ensure that steel alloy of the present invention has
There is excellent hardness and strength character, while having toughness and good welding performance very high.Alloying element Mn, Cr, Ni,
The addition of Mo and its suitable proportioning selection, effectively can further improve intensity, hardness and the toughness of the steel alloy
Can, and can guarantee that whole part section can reach the uniformity and uniformity of tissue and performance.The addition of alloy element Al and Nb
And its suitable proportioning selection, then can effectively suppress Austenite Grain Growth in forging and heat treatment process, crystal grain thinning is carried
The intensity of the high steel alloy, plasticity and toughness.
The invention further relates to the manufacture method of described heavy haul railway railway frog highly wear-resisting alloy steel, including carry out in order
Following steps:Electric arc furnace smelting → ladle furnace refining → vacuum drying oven degassing → molding → breaking down cogging → forging molding → dehydrogenation
Heat treatment → finished heat treatment;Wherein forging molding should use open die forging+die forging mode, and finished heat treatment method is in austenite
Cooling should be controlled with 0.1 DEG C/s~0.8 DEG C/s after change, be cooled to after room temperature temper again.
Preferably for the manufacture of 75Kg/m railway frogs, finished heat treatment can be laggard using 890 DEG C~980 DEG C austenitizings
Row is air cooled to room temperature, and then cooling velocity is tempered in 0.3 DEG C/s~0.5 DEG C/s in 160 DEG C~550 DEG C insulations.
Preferably for the manufacture of 60Kg/m railway frogs, finished heat treatment can be laggard using 890 DEG C~980 DEG C austenitizings
Row is air cooled to room temperature, and then cooling velocity is tempered in 0.5 DEG C/s~0.8 DEG C/s in 160 DEG C~550 DEG C insulations.
Compared with prior art, railroad frog highly wear-resisting alloy steel one of the present invention be using C, Mn, Cr, Ni,
The addition of Mo, Al, Nb and its suitable proportioning selection, effectively raise intensity, hardness and the toughness properties of abrasion-resistant stee, it is ensured that
The uniformity and uniformity of whole part section tissue and performance.Two is using the system control smelted, forge and be heat-treated
Method, reduces the segregation of the alloying element of steel ingot, improves the uniformity of forging section performance and the stability of inherent quality.
Railroad frog of the invention is as follows with highly wear-resisting alloy steel mechanical performance index:Rm>=1605MPa, Rp0.2>=1300MPa, hardness
>=48HRC, αKU(room temperature) >=100J/cm2, αKU(-40℃)≥70J/cm2.At present, commercial alloy steel frog index of correlation
Following (fortune baseline road (2005) 230 file of technical requirements《Alloy steel core rail assembled frog technical conditions》), Rm≥
1240MPa, αKU(room temperature) >=70J/cm2, αKU(-40℃)≥35J/cm2, hardness is 38~45HRC.Choose typical commercialization rut
Fork is tested, and its component and its mass percent are matched:C 0.25、Si 2.08、Mn 1.69、P 0.008、S 0.002、Cr
1.40th, Ni 0.30, Mo 0.28, Al 0.03, Nb 0.01, O 18ppm, N 74ppm, H 0.39ppm, balance of iron and other
Inevitable impurity.Its mechanical properties results is after testing:RmIt is 1263MPa, Rp0.2It is 1020MPa, hardness is 39.5HRC
~42.0HRC, αKU(room temperature) is 74J/cm2, αKU(- 40 DEG C) is 37J/cm2.As can be seen here, above-mentioned performance indications are than existing
Commercial railway frog has being obviously improved by a relatively large margin.
In a word, steel alloy of the present invention has a Performance Characteristics of high intensity, high rigidity, high tenacity, and section performance
The good stability of uniformity and inherent quality, is particularly well-suited to the demand of high-speed overload railroad frog, and with the use longevity high
Life, it is easily fabricated, be easily assembled to the features such as using.
With reference to specific embodiment, the present invention will be described in detail.Protection scope of the present invention is not with specific implementation
Mode is limited, but is defined in the claims.
Specific embodiment
About it is of the present invention and technology contents, feature and effect, will describe in detail in the following specific embodiments.
However, it will be apparent to those skilled in the art that embodiment herein is used only for example purpose, the invention is not limited in this.
In the present invention, the measure accepted standard of room temperature tensile properties is GB/T228-2002《Metal material room temperature tensile
Test method》, the measure accepted standard of impact property is GB/T229-2007《Metal material Charpy pendulum impact test side
Method》, the conversion method accepted standard of α KU is GB/T229-1984《Metal Charpy (U-shaped breach) impact test method》, hardness
The measure accepted standard of performance is GBT 230.1-2009 metal material Rockwell hardness test part 1s:Test method (A, B,
C, D, E, F, G, H, K, N, T scale).
Railroad frog highly wear-resisting alloy steel of the invention, is the steel alloy of a kind of high intensity, high rigidity, high tenacity, special
Not Shi Yongyu high-speed overload railroad frog, its component and its mass percent are as follows:C 0.29%~0.45%, Si 0.20%
~0.59%, Mn 0.90%~1.51%, P≤0.015%, S≤0.010%, Cr 1.52%~1.79%, Ni1.01%~
1.49%th, Mo 0.29%~0.59%, Al 0.02%~0.07%, Nb 0.025%~0.10%, 0.05%≤Nb+Al≤
0.15%th, [O]≤20ppm, [N]≤100ppm, [H]≤0.50ppm, balance of iron and other inevitable impurity.
The manufacture method of described highly wear-resisting alloy steel, including the following steps for carrying out in order:Electric arc furnace smelting → steel
Bag stove refining → vacuum drying oven degassing → molding → breaking down cogging → forging molding → dehydrogenation heat treatment → finished heat treatment;Wherein forge
Causing type should use open die forging+die forging mode, and finished heat treatment method is should be with 0.1 DEG C/s~0.8 DEG C/s after austenitizing
Cooling is controlled, room temperature is cooled to and is tempered at a certain temperature again.
Each operation is specially in above-mentioned manufacturing process flow:
Electric arc furnace smelting:By oxidation and reduction refining, P and S, degassing are gone, remove field trash, control adjusts chemical composition,
Obtain more pure molten steel.
Ladle furnace refining:The pure molten steel that electric arc furnace smelting is obtained is poured into ladle furnace, is refined, it is further accurate
Control chemical composition, removes S and gas content.
Vacuum drying oven deaerates:The more pure molten steel adjusted through ladle furnace is poured into vacuum drying oven, under vacuo oxygen blast, de-
Carbon, vacuum degassing, alloying component fine setting, obtain the molten steel of final purification and precise control.
Molding:Qualified pure molten steel is poured into ingot shape, the small steel ingot of the uniform and degree of segregation of densification is obtained, is
Rolling is got ready.
Breaking down cogging:The steel ingot for obtaining will be molded carries out cogging, to ensure the uniformity of steel ingot each several part and reduce loose
Degree, is that forging molding is got ready.
Forging molding:After the steel billet of breaking down is carried out into preliminary open die forging, and final forging molding is carried out with die forging.
Dehydrogenation is heat-treated:The forging of forging molding is carried out into dehydrogenation, to greatly improve the impact flexibility of forging.
Finished heat treatment:Forging after dehydrogenation is heat-treated carries out the final heat treatment of tissue and performance.
According to prioritization scheme, finished heat treatment should be controlled cold generally after austenitizing with 0.1 DEG C/s~0.8 DEG C/s
But, need to carry out the tempering of uniform temperature after cooling.Such as manufacture the manufacture of 75Kg/m railway frogs, finished heat treatment can using 890 DEG C~
Carry out being air cooled to room temperature after 980 DEG C of austenitizings, then cooling velocity protects in 0.3 DEG C/s~0.5 DEG C/s at 160 DEG C~550 DEG C
Temperature tempering.And for the manufacture of 60Kg/m railway frogs, finished heat treatment carries out air cooling after can using 890 DEG C~980 DEG C austenitizings
To room temperature, then cooling velocity is tempered in 0.5 DEG C/s~0.8 DEG C/s in 160 DEG C~550 DEG C insulations.
Embodiment 1:Highly wear-resisting alloy steel of the invention, its each component and its mass percent are matched:C 0.30、Si
0.52、Mn 1.27、P 0.007、S 0.004、Cr 1.64、Ni 1.29、Mo 0.44、Al 0.07、Nb 0.04、O 18ppm、
N 76ppm, H 0.36ppm, balance of iron and other inevitable impurity.Its mechanical properties results is after testing:RmFor
1685MPa, Rp0.2It is 1367MPa, hardness is 51.5HRC, αKU(room temperature) is 134J/cm2, αKU(- 40 DEG C) is 92J/cm2。
Embodiment 2:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C 0.29、
Si 0.45、Mn 1.51、P 0.006、S 0.006、Cr 1.67、Ni 1.47、Mo 0.41、Al 0.05、Nb 0.10、O
18ppm, N 79ppm, H 0.43ppm, balance of iron and other inevitable impurity.Its mechanical properties results is after testing:
RmIt is 1701MPa, Rp0.2It is 1370MPa, hardness is 52.0HRC, αKU(room temperature) is 112J/cm2, αKU(- 40 DEG C) is 79J/cm2。
Embodiment 3:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C 0.38、
Si 0.20、Mn 1.29、P 0.009、S 0.004、Cr 1.75、Ni 1.01、Mo 0.56、Al 0.07、Nb 0.08、O
15ppm, N 78ppm, H 0.42ppm, balance of iron and other inevitable impurity.Its mechanical properties results is after testing:
RmIt is 1723MPa, Rp0.2It is 1384MPa, hardness is 52.5HRC, αKU(room temperature) is 137J/cm2, αKU(- 40 DEG C) is 93J/cm2。
Embodiment 4:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C 0.33、
Si 0.59、Mn 1.01、、P 0.009、S 0.001、Cr 1.61、Ni 1.22、Mo 0.57、Al 0.06、Nb 0.09O
20ppm, N 75ppm, H 0.46ppm, balance of iron and other inevitable impurity.Its mechanical properties results is after testing:
RmIt is 1719MPa, Rp0.2It is 1377MPa, hardness is 52.5HRC, αKU(room temperature) is 138J/cm2, αKU(- 40 DEG C) is 94.5J/
cm2。
Embodiment 5:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C 0.39、
Si 0.21、Mn 1.36、P 0.008、S 0.004、Cr 1.72、Ni 1.21、Mo 0.29、Al 0.07、Nb 0.07、O
14ppm, N 77ppm, H 0.41ppm, balance of iron and other inevitable impurity.Its mechanical properties results is after testing:
RmIt is 1625MPa, Rp0.2It is 1321MPa, hardness is 50.5HRC, αKU(room temperature) is 145J/cm2, αKU(- 40 DEG C) is 101J/
cm2。
Embodiment 6:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C 0.29、
Si 0.30、Mn 1.32、P 0.009、S 0.002、Cr 1.79、Ni 1.24、Mo 0.59、Al 0.02、Nb 0.03、O
20ppm, N 98ppm, H 0.35ppm, balance of iron and other inevitable impurity.Its mechanical properties results is such as after testing
For:RmIt is 1653MPa, Rp0.2It is 1331MPa, hardness is 51.0HRC, αKU(room temperature) is 129J/cm2, αKU(- 40 DEG C) is 88J/
cm2。
Embodiment 7:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C 0.37、
Si 0.39、Mn 1.17、P 0.007、S 0.003、Cr 1.54、Ni 1.26、Mo 0.36、Al 0.04、Nb 0.05、O
19ppm, N 65ppm, H 0.33ppm, balance of iron and other inevitable impurity.Its mechanical properties results is after testing:
RmIt is 1631MPa, Rp0.2It is 1323MPa, hardness is 50.5HRC, αKU(room temperature) is 141J/cm2, αKU(- 40 DEG C) is 99J/cm2。
Embodiment 8:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C 0.38、
Si 0.47、Mn 0.92、P 0.007、S 0.001、Cr 1.55、Ni 1.49、Mo 0.37、Al 0.06、Nb 0.06、O
16ppm, N 82ppm, H 0.41ppm, balance of iron and other inevitable impurity.Its mechanical properties results is after testing:
RmIt is 1709MPa, Rp0.2It is 1374MPa, hardness is 52.0HRC, αKU(room temperature) is 114J/cm2, αKU(- 40 DEG C) is 83J/cm2。
Embodiment 9:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C 0.36、
Si 0.41、Mn 1.34、P 0.008、S 0.002、Cr 1.52、Ni 1.08、Mo 0.47、Al 0.06、Nb 0.08、O
17ppm, N 98ppm, H 0.45ppm, balance of iron and other inevitable impurity.Its mechanical properties results is after testing:
RmIt is 1701MPa, Rp0.2It is 1369MPa, hardness is 52.0HRC, αKU(room temperature) is 119J/cm2, αKU(- 40 DEG C) is 91J/cm2。
Embodiment 10:Heavy haul railway railway frog highly wear-resisting alloy steel, its each component and its mass percent are matched:C
0.45、Si 0.24、Mn 0.90、P 0.006、S 0.001、Cr 1.58、Ni 1.05、Mo 0.45、Al 0.07、Nb 0.03、
O 16ppm, N 88ppm, H 0.35ppm, balance of iron and other inevitable impurity.Its mechanical properties results after testing
For:RmIt is 1629MPa, Rp0.2It is 1321MPa, hardness is 50.5HRC, αKU(room temperature) is 142J/cm2, αKU(- 40 DEG C) are
103J/cm2。
Embodiment 11:A kind of manufacture method of the heavy haul railway railway frog highly wear-resisting alloy steel of high-intensity high-tenacity, manufacture
Technological process is the following steps for carrying out in order:Electric arc furnace smelting → ladle furnace refining → vacuum drying oven degassing → molding → breaking down
Cogging → forging molding → dehydrogenation heat treatment → finished heat treatment.Wherein forging molding uses open die forging+die forging.Dehydrogenation is heat-treated
For steel alloy provides the high tenacity Technology for Heating Processing to be carried out.Finished heat treatment enters according to the difference of forging size and composition
Row control cooling.Finished heat treatment is generally controlled cooling after austenitizing with 0.1 DEG C/s~0.8 DEG C/s, cools down laggard
The tempering of row uniform temperature.
Embodiment 12:For the manufacture of 75Kg/m railway frogs, finished heat treatment is laggard using 890 DEG C~980 DEG C austenitizings
Row is air cooled to room temperature, and cooling velocity is in 0.3 DEG C/s~0.5 DEG C/s;Then in 160 DEG C~550 DEG C insulation tempering.
Embodiment 13:For the manufacture of 60Kg/m railway frogs, finished heat treatment is laggard using 890 DEG C~980 DEG C austenitizings
Row is air cooled to room temperature, and cooling velocity is in 0.5 DEG C/s~0.8 DEG C/s;Then in 160 DEG C~550 DEG C insulation tempering.
Embodiment 14:One group of preferred embodiment of high-speed overload railroad frog highly wear-resisting alloy steel, its component and matter
Amount percentage proportioning is as shown in the table.After tested, the mechanical performance index of highly wear-resisting alloy steel can reach in this group of embodiment
It is claimed below:Rm>=1605MPa, Rp0.2>=1300MPa, hardness >=48HRC, αKU(room temperature) >=100J/cm2, αKU(-40℃)≥
70J/cm2。