CN102876994A - Heat resistant steel for worm gear member and manufacture method of heat resistant steel - Google Patents
Heat resistant steel for worm gear member and manufacture method of heat resistant steel Download PDFInfo
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- CN102876994A CN102876994A CN 201210420631 CN201210420631A CN102876994A CN 102876994 A CN102876994 A CN 102876994A CN 201210420631 CN201210420631 CN 201210420631 CN 201210420631 A CN201210420631 A CN 201210420631A CN 102876994 A CN102876994 A CN 102876994A
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- 229910000831 Steel Inorganic materials 0.000 claims description 22
- 239000010959 steel Substances 0.000 claims description 22
- 238000000034 method Methods 0.000 claims description 19
- 229910001018 Cast iron Inorganic materials 0.000 claims description 18
- 239000012535 impurity Substances 0.000 claims description 15
- 238000000137 annealing Methods 0.000 claims description 11
- 229910052684 Cerium Inorganic materials 0.000 claims description 9
- 238000009413 insulation Methods 0.000 claims description 8
- 239000000155 melt Substances 0.000 claims description 8
- 229910052702 rhenium Inorganic materials 0.000 claims description 8
- 238000007670 refining Methods 0.000 claims description 6
- 229910052782 aluminium Inorganic materials 0.000 claims description 5
- 229910052804 chromium Inorganic materials 0.000 claims description 5
- 229910052735 hafnium Inorganic materials 0.000 claims description 5
- 229910052727 yttrium Inorganic materials 0.000 claims description 5
- 229910052726 zirconium Inorganic materials 0.000 claims description 5
- 229910052796 boron Inorganic materials 0.000 claims description 4
- 229910052802 copper Inorganic materials 0.000 claims description 4
- 229910052748 manganese Inorganic materials 0.000 claims description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims description 4
- 229910052758 niobium Inorganic materials 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 239000000126 substance Substances 0.000 claims description 4
- 229910052721 tungsten Inorganic materials 0.000 claims description 4
- 230000006698 induction Effects 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 238000005266 casting Methods 0.000 claims description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 2
- 230000001105 regulatory effect Effects 0.000 claims description 2
- 239000011651 chromium Substances 0.000 description 7
- 229910052729 chemical element Inorganic materials 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 229910052761 rare earth metal Inorganic materials 0.000 description 3
- 229910052715 tantalum Inorganic materials 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 229910019580 Cr Zr Inorganic materials 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 230000002688 persistence Effects 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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- Heat Treatment Of Sheet Steel (AREA)
Abstract
The invention provides heat resistant steel for a worm gear member. Through a special chemical composition and a manufacture method, the worm gear member has better high-temperature durability and creep property at a temperature of 670 DEG C. On the basis of the traditional heat resistant steel, elements such as Zr, Hf, Ta and Al are added, elements such as V, Ni and Co are reduced, the content of the Cr is lowered, the manufacture method is improved, different chemical elements are added in batches and secondary tempering and annealing are carried out under special conditions, therefore, the high-temperature durability and the creep property of the worm gear member at a temperature of 670 DEG C are improved, and the firm foundation is laid for further increasing generation power of a steam turbine.
Description
Technical field
The present invention relates to a kind of high temperature steel, especially a kind of high temperature steel for turbine component such as turbine blade and rotor and preparation method thereof.
Background technology
Development along with prior art, in order further to improve generating efficiency, temperature to steam turbine is more and more higher, and the high temperature steel of prior art is mainly high chromium content ferrite high temperature steel, is up to 650 its high temperature resistant persistence and creep properties will significantly reduce about 620 degree.
Summary of the invention
The invention provides a kind of high temperature steel for turbine component, by its unique chemical constitution and making method, make turbine component when 670 spend, still have good high temperature durability and creep properties.
The present invention has added the elements such as Zr, Hf, Ta, Al on the basis of existing high temperature steel, the elements such as V, Ni, Co have been reduced, and reduced the content of Cr, improved making method, add in batches different chemical elements and carry out under given conditions double tempering and annealing, improve by this, improved high temperature durability and the creep properties of turbine component under 670 degree conditions, for the generated output that further improves steam turbine lays a solid foundation.
The invention provides a kind of high temperature steel for turbine component, the chemical constitution of high temperature steel is below to be all weight percent:
C:0.02-0.4,Cr:2.6-4.8,
Zr:0.9-2.7,Hf:0.2-0.6,
Ta:0.8-1.0,Nb:0.2-0.3,
Mn:0.4-0.8,Mo:2.0-3.0,
W:1.5-1.8,N:0.1-0.2,
B:0.02-0.04,Si:0.2-0.4,
Cu:0.6-0.7,Al:0.2-0.23,
Surplus is Fe and impurity thereof, wherein Zr: Hf 〉=5: 1, Cu: Al 〉=3: 1, Zr+Hf+Ta+Nb 〉=3.0.
Preferred scheme is content of impurities≤0.1.
Preferred scheme is in the impurity:
P≤0.01,S≤0.01,Zn≤0.005,Sb≤0.01。
Preferred scheme is for also comprising Re, and Re content is 0.1-0.5.
Preferred scheme is that Re is Ce and Y, Ce: Y 〉=3: 1.
The present invention provides a kind of method of making the high temperature steel of turbine component in addition, mainly is comprised of following steps:
(1) with cast iron just refining in non-vacuum induction furnace, when treating that cast iron begins to melt, adds W, Zr, Hf, Nb, the Ta element, when cast iron melts fully, add Si, Cu, Mn, Mo, B, Cr, Al, cast iron melt adding C and N after 15 minutes fully, and the ratio of regulating each element, make it meet C:0.02-0.4, Cr:2.6-4.8, Zr:0.9-2.7, Hf:0.2-0.6, Ta:0.8-1.0, Nb:0.2-0.3, Mn:0.4-0.8, Mo:2.0-3.0, W:1.5-1.8, N:0.1-0.2, B:0.02-0,04, Si:0.2-0.4, Cu:0.6-0.7, Al:0.2-0.23, Zr: Hf 〉=5: 1 wherein, Cu: Al 〉=3: 1, Zr+Hf+Ta+Nb 〉=3.0, solution casting becomes consumable electrode;
(2) with consumable electrode remelting refining in electroslag furnace, further the content of impurity reduction element makes it meet design requirements, makes ESR ingot;
(3) ESR ingot is made turbine component, turbine component is carried out anneal, treatment step and processing parameter are:
Turbine component is heated to 1150 degree, is incubated after 4 hours, insulation 800 degree are incubated 24 hours in annealing furnace, are cooled to normal temperature, further are heated to 750 degree, are incubated after 2 hours, and insulation 650 degree are incubated 5 hours in annealing furnace, are cooled to normal temperature.
Preferred scheme is impurity element total content≤0.1.
Preferred scheme is in the impurity element:
P≤0.01,S≤0.01,Zn≤0.005,Sb≤0.01。
Preferred scheme is in the step (1), when cast iron melts fully, also be added with Re, and Re content is 0.1-0.5.
Preferred scheme is that Re is Ce and Y, Ce: Y 〉=3: 1.
Sample of the present invention process under 670 degree conditions detects:
Yield strength σ
0.02〉=729N/mm
2
Tensile strength sigma
b〉=989N/mm
2
Elongation δ 〉=13%
Relative reduction in area ψ 〉=60%
Ballistic work AKv 〉=40J
Sample of the present invention is 670 degree in temperature, and stress is 235N/mm
2Process detects under the condition:
Rupture time (Hr) 〉=110 hour.
The high temperature steel that the present invention makes by its unique chemical constitution and manufacture craft under 670 degree temperature, has good high-temperature and durable and creep properties.
Embodiment
Below the present invention is further detailed explanation.
Embodiment 1
Following table is five samples, and the content of chemical element is as follows in each sample:
Prescription | C | Cr | Zr | Hf | Ta | Nb | Mn | Mo | W | N | B | Si | Cu | Al |
Sample 1 | 0.1 | 3 | 1.8 | 0.2 | 0.9 | 0.2 | 0.6 | 2.2 | 1.6 | 0.1 | 0.03 | 0.3 | 0.6 | 0.2 |
Sample 2 | 0.15 | 4.2 | 2.6 | 0.4 | 0.8 | 0.2 | 0.7 | 3.0 | 1.5 | 0.2 | 0.04 | 0.4 | 0.7 | 0.22 |
Sample 3 | 0.2 | 4.6 | 2.7 | 0.5 | 1.0 | 0.3 | 0.8 | 2.0 | 1.7 | 0.15 | 0.02 | 0.2 | 0.6 | 0.2 |
Sample 4 | 0.3 | 2.6 | 2.6 | 0.5 | 0.9 | 0.3 | 0.4 | 2.5 | 1.8 | 0.15 | 0.03 | 0.3 | 0.6 | 0.2 |
Sample 5 | 0.4 | 4.6 | 1.8 | 0.3 | 0.9 | 0.2 | 0.5 | 2.8 | 1.6 | 0.18 | 0.02 | 0.2 | 0.7 | 0.22 |
Under 670 degree conditions, pressure is 28MPa to sample 1-5, and stress is 235N/mm
2Condition under detect, the result is as follows:
σ 0.02 | σ b | δ | ψ | AKv | Hr | |
Sample 1 | 739 | 991 | 14 | 61 | 40 | 112 |
Sample 2 | 743 | 1012 | 15 | 62 | 42 | 115 |
Sample 3 | 790 | 1038 | 15 | 62 | 46 | 115 |
Sample 4 | 788 | 1026 | 15 | 60 | 41 | 113 |
Sample 5 | 736 | 995 | 14 | 61 | 42 | 111 |
By the above results and contrast, can learn that product high temperature durability of the present invention and creep properties have all obtained significantly providing, especially under 670 degree working conditions.
Embodiment 2
The main checked for impurities of present embodiment adds respectively following impurity to the impact of its characteristic on the basis of sample 3, be labeled as sample 31, sample 32, and sample 33:
P | S | Zn | Sb | |
Sample 31 | 0.01 | 0.01 | 0.005 | 0.01 |
Sample 32 | 0.02 | 0.02 | 0.012 | 0.03 |
Sample 33 | 0.02 | 0.02 | 0.030 | 0.03 |
Under 670 degree conditions, pressure is under the condition of 28MPa, detects to sample 31-33, and the result is as follows:
σ 0.02 | σ b | δ | ψ | AKv | Hr | |
Sample 31 | 789 | 1039 | 15 | 61 | 46 | 113 |
Sample 32 | 742 | 908 | 12 | 58 | 36 | 96 |
Sample 33 | 632 | 765 | 8 | 56 | 28 | 63 |
By above result, can learn, in P≤0.01, S≤0.01, Zn≤0.005 in the situation of Sb≤0.01, does not basically affect performance, otherwise will have a strong impact on performance, especially in the situation that Zn increases.
Embodiment 3
Present embodiment Re (rare earth element) adds respectively following impurity to the impact of its characteristic on the basis of sample 1, be labeled as sample 11, sample 12, and sample 13:
Rare earth (total amount) | Ce | Y | Other rare earth element | |
Sample 11 | 0.04 | Arbitrarily | Arbitrarily | Contain |
Sample 12 | 0.04 | 0.03 | 0.01 | Do not contain |
Sample 13 | 0.04 | 0.01 | 0.03 | Do not contain |
Under 670 degree conditions, pressure is under the condition of 28MPa, detects to sample 11-13, and the result is as follows:
σ 0.02 | σ b | δ | ψ | AKv | Hr | |
Sample 11 | 750 | 1008 | 14 | 63 | 42 | 118 |
Sample 12 | 780 | 1152 | 16 | 68 | 48 | 132 |
Sample 13 | 766 | 1076 | 15 | 63 | 43 | 120 |
By above result, can learn, add Re, can improve the performance of sample, especially add Ce and Y, particularly Ce: Y 〉=3: 1 o'clock, performance is better.
Embodiment 4
On the basis of sample 2, make by diverse ways, be designated as respectively sample 21, sample 22, sample 23, sample 24, sample 25 ordinary methods of the present invention and be:
Ordinary method of the present invention is with cast iron just refining in non-vacuum induction furnace, and after cast iron dissolved fully, all chemical elements of disposable adding were reconciled the content of each element, make consumable electrode; And carry out the electroslag furnace remelting refining, and make turbine component, be the melting method of sample 21;
On the basis of ordinary method, when treating that cast iron begins to melt, add W, Zr, Hf, Nb, Ta element, when cast iron melts fully, add Si, Cu, Mn, Mo, B, Cr, Al, cast iron melts adding C and N after 15 minutes fully, realize in batches each element, be the melting method of sample 22;
On the basis of ordinary method, turbine component is heated to 1150 degree, be incubated after 4 hours, insulation 800 degree in annealing furnace, be incubated 24 hours, be cooled to normal temperature, carry out second annealing, be heated to 750 degree, be incubated after 2 hours, insulation 650 degree are incubated 5 hours in annealing furnace, be cooled to normal temperature, be the melting method of sample 23;
On the basis of ordinary method, when treating that cast iron begins to melt, add W, Zr, Hf, Nb, Ta element, when cast iron melts fully, add Si, Cu, Mn, Mo, B, Cr, Al, cast iron melts adding C and N after 15 minutes fully, realize entering in batches each element, and turbine component is heated to 1150 degree, and be incubated after 4 hours, insulation 800 is spent in annealing furnace, be incubated 24 hours, be cooled to normal temperature, further be heated to 750 degree, be incubated after 2 hours, insulation 650 degree in annealing furnace, be incubated 5 hours, be cooled to normal temperature, be the melting method of sample 24.
σ 0.02 | σ b | δ | ψ | AKv | Hr | |
Sample 21 | 653 | 812 | 10 | 56 | 36 | 80 |
Sample 22 | 692 | 932 | 13 | 60 | 40 | 96 |
Sample 23 | 691 | 923 | 13 | 61 | 38 | 95 |
Sample 24 | 743 | 1012 | 15 | 62 | 42 | 115 |
Can learn by above result, add in batches different chemical elements, and carry out second annealing and process, can improve the performance of product.
Above content be in conjunction with structure of the present invention and working process to its further description of doing, can not assert that implementation of the present invention is confined to these explanations.For the general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, can also make some simple deduction or replace, all should be considered as belonging to protection scope of the present invention.
Claims (10)
1. high temperature steel that is used for turbine component, it is characterized in that: the chemical constitution of described steel is below to be all weight percent:
C:0.02-0.4,Cr:2.6-4.8,
Zr:0.9-2.7,Hf:0.2-0.6,
Ta:0.8-1.0,Nb:0.2-0.3,
Mn:0.4-0.8,Mo:2.0-3.0,
W:1.5-1.8,N:0.1-0.2,
B:0.02-0.04,Si:0.2-0.4,
Cu:0.6-0.7,Al:0.2-0.23,
Surplus is Fe and impurity thereof, wherein Zr: Hf 〉=5: 1, Cu: Al 〉=3: 1, Zr+Hf+Ta+Nb 〉=3.0.
2. the high temperature steel for turbine component according to claim 1 is characterized in that: described content of impurities≤0.1.
3. the high temperature steel for turbine component according to claim 2 is characterized in that: in the described impurity: P≤0.01, S≤0.01, Zn≤0.005, Sb≤0.01.
4. the high temperature steel for turbine component according to claim 1, it is characterized in that: also comprise Re, Re content is 0.1-0.5.
5. the high temperature steel for turbine component according to claim 4, it is characterized in that: described Re is Ce and Y, Ce: Y 〉=3: 1.
6. method of making the high temperature steel of turbine component mainly is comprised of following steps:
(1) with cast iron just refining in non-vacuum induction furnace, when treating that cast iron begins to melt, adds W, Zr, Hf, Nb, the Ta element, when cast iron melts fully, add Si, Cu, Mn, Mo, B, Cr, Al, cast iron melt adding C and N after 15 minutes fully, and the ratio of regulating each element, make it meet C:0.02-0.4, Cr:2.6-4.8, Zr:0.9-2.7, Hf:0.2-0.6, Ta:0.8-1.0, Nb:0.2-0.3, Mn:0.4-0.8, Mo:2.0-3.0, W:1.5-1.8, N:0.1-0.2, B:0.02-0,04, Si:0.2-0.4, Cu:0.6-0.7, Al:0.2-0.23, Zr: Hf 〉=5: 1 wherein, Cu: Al 〉=3: 1, Zr+Hf+Ta+Nb 〉=3.0, solution casting becomes consumable electrode;
(2) with consumable electrode remelting refining in electroslag furnace, further the content of impurity reduction element makes it meet design requirements, makes ESR ingot;
(3) ESR ingot is made turbine component, turbine component is carried out anneal, treatment step and processing parameter are:
Turbine component is heated to 1150 degree, is incubated after 4 hours, insulation 800 degree are incubated 24 hours in annealing furnace, are cooled to normal temperature, further are heated to 750 degree, are incubated after 2 hours, and insulation 650 degree are incubated 5 hours in annealing furnace, are cooled to normal temperature.
7. the method for the high temperature steel of making turbine component according to claim 6 is characterized in that: described impurity element total content≤0.1.
8. the method for the high temperature steel of making turbine component according to claim 7 is characterized in that: in the described impurity element:
P≤0.01,S≤0.01,Zn≤0.005,Sb≤0.01。
9. the method for the high temperature steel of making turbine component according to claim 6 is characterized in that: in the described step (1), when cast iron melts fully, also be added with Re, and Re content is 0.1-0.5.
10. the method for the high temperature steel of making turbine component according to claim 9, it is characterized in that: described Re is Ce and Y, Ce: Y 〉=3: 1.
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Cited By (5)
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CN103882329A (en) * | 2014-02-18 | 2014-06-25 | 芜湖市鸿坤汽车零部件有限公司 | Alloy material for internal combustion engine valve seats and preparation method thereof |
CN104032236A (en) * | 2014-06-27 | 2014-09-10 | 南京赛达机械制造有限公司 | Turbine blade capable of improving thermal cracking resistance and production process thereof |
CN108950412A (en) * | 2018-08-09 | 2018-12-07 | 宁国市挚友合金钢材料有限公司 | A kind of heat proof material and preparation method thereof for electric furnace accessory |
CN109477190A (en) * | 2016-07-28 | 2019-03-15 | 博格华纳公司 | Ferritic steel for turbocharger |
CN110938781A (en) * | 2019-10-30 | 2020-03-31 | 武汉科技大学 | Low-cost high-aluminum heat-resistant steel and preparation method thereof |
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2012
- 2012-10-24 CN CN 201210420631 patent/CN102876994A/en active Pending
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103882329A (en) * | 2014-02-18 | 2014-06-25 | 芜湖市鸿坤汽车零部件有限公司 | Alloy material for internal combustion engine valve seats and preparation method thereof |
CN104032236A (en) * | 2014-06-27 | 2014-09-10 | 南京赛达机械制造有限公司 | Turbine blade capable of improving thermal cracking resistance and production process thereof |
CN109477190A (en) * | 2016-07-28 | 2019-03-15 | 博格华纳公司 | Ferritic steel for turbocharger |
CN108950412A (en) * | 2018-08-09 | 2018-12-07 | 宁国市挚友合金钢材料有限公司 | A kind of heat proof material and preparation method thereof for electric furnace accessory |
CN110938781A (en) * | 2019-10-30 | 2020-03-31 | 武汉科技大学 | Low-cost high-aluminum heat-resistant steel and preparation method thereof |
CN110938781B (en) * | 2019-10-30 | 2021-02-19 | 武汉科技大学 | Low-cost high-aluminum heat-resistant steel and preparation method thereof |
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