CN110484703A - The heat treatment process of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement - Google Patents
The heat treatment process of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement Download PDFInfo
- Publication number
- CN110484703A CN110484703A CN201910811630.XA CN201910811630A CN110484703A CN 110484703 A CN110484703 A CN 110484703A CN 201910811630 A CN201910811630 A CN 201910811630A CN 110484703 A CN110484703 A CN 110484703A
- Authority
- CN
- China
- Prior art keywords
- temperature
- heat treatment
- grain size
- casting
- ultralow
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
- C21D1/28—Normalising
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
A kind of heat treatment process of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement of the present invention keeps the temperature normalizing process using a staged, specifically includes the following steps: workpiece is heated to 600-700 DEG C with≤70 DEG C/h heating rate, keeps the temperature 2-6 hours；Continue to be heated to 1000-1100 DEG C of solid solution temperature with 70~100 DEG C/h heating rate, heat preservation；Temperature is dropped to 800-950 DEG C with the speed of 70~100 DEG C/h again, heat preservation；Then it is rapidly heated with the speed of 80~120 DEG C/h to 900-1000 DEG C, is kept the temperature；Using misting cooling to 500 DEG C hereinafter, then proceeding to air-cooled to 300 DEG C hereinafter, continuing to be air-cooled to 100 DEG C or less.The beneficial effects of the present invention are: crystal grain can be refined disposably, meets flaw detection and require, while can also effectively reduce production cost, it is energy saving.
Description
Technical field
The present invention relates to steel-casting technical field of heat treatment, more particularly to the thick big section Mo ultralow-carbon martensitic steel-casting of refinement
The heat treatment process of grain size.
Background technique
China is that waterpower resourses country extremely abundant, hydroelectric generation have become the main energy source in China in the world
One of.In recent years, the theory of " low-carbon environment-friendly " is known together, and the power of water turbine set has also risen to 100 from 700,000 multikilowatts
The stainless cast steel part wall thickness of ten thousand multikilowatts, large-sized water turbine unit is increasing, and performance requirement is higher and higher, and delivery cycle is also more next
It is shorter.With the increase of wall thickness, the harden ability of material is limited, causes performance uneven；Due to the tissue heredity of high-alloy steel,
The increase of wall thickness leads to not carry out flaw detection operation but also mixed crystal state further deteriorates, generally require to carry out full annealing,
The processes such as normalizing, detection grain size, secondary normalizing, detection grain size, tempering are just able to satisfy performance and flaw detection requires (as schemed
Shown in 4).So, the castings production period is very long, and resource cost is serious.How normalizing process is optimized, reaches guarantee
The uniformity consistency of product mechanical performance, grain size, purpose that is energy saving, reducing cost, shortening production cycle, becomes row
The direction of industry in-house research.
Summary of the invention
The object of the present invention is to provide a kind of heat treatment works of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement
Skill can disposably refine crystal grain, meet flaw detection and require, while can also effectively reduce production cost, energy saving.
In order to achieve the above object, the present invention is implemented with the following technical solutions:
The heat treatment process of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement, just using a staged heat preservation
Fire process, specifically includes the following steps:
1) it heats up: workpiece being heated to 600-700 DEG C with≤70 DEG C/h heating rate, keeps the temperature 2-6 hours；
2) continue to be heated to 1000-1100 DEG C of solid solution temperature with 70~100 DEG C/h heating rate, heat preservation；
3) temperature is dropped to 800-950 DEG C with the speed of 70~100 DEG C/h again, heat preservation；
4) it is then rapidly heated with the speed of 80~120 DEG C/h to 900-1000 DEG C, is kept the temperature；
5) cooling: using misting cooling to 500 DEG C hereinafter, then proceeding to air-cooled to 300 DEG C hereinafter, continuing to be air-cooled to 100
DEG C or less.
Above-mentioned steps 2) in soaking time press 25~50mm/h of casting section thickness heat preservation.
Above-mentioned steps 3) in soaking time be 6-10 hour, above-mentioned steps 4) in soaking time be 4-8 hours.
Compared with prior art, the beneficial effects of the present invention are:
1) present invention eliminates the full annealing processing steps in routine techniques, and original double normalizing is changed to once
Normalizing shortens the production cycle, saves time and the energy；
2) present invention inhibits Austenite Grain Growth using high temperature solid solution+low temperature, reaches the thin of the uniform grain size of ingredient
The purpose of change；
3) present invention is increased degree of supercooling and cooling velocity, is further suppressed the length of grain size by the way of misting cooling
Greatly；
4) according to transformation temperature, the different types of cooling is used in different temperatures section, both ensure that the uniform of casting crystalline grain degree,
Also assure that casting will not cause to crack because of cooling velocity is too fast.
Detailed description of the invention
Fig. 1 is Mo ultralow-carbon martensitic steel-casting heat treatment normalizing process curve graph of the invention；
Fig. 2 is the steel-casting heat treatment cycle curve figure of the embodiment of the present invention 1；
Fig. 3 is that embodiment 1 uses heat treatment process product grains degree crystalline phase figure obtained of the invention；
Fig. 4 is that the casting of embodiment 1 uses the heat treatment cycle curve figure of common process；
Fig. 5 is the casting of embodiment 1 using normative heat treatment technique product grains degree crystalline phase figure obtained.
Specific embodiment
Specific embodiments of the present invention will be further explained with reference to the accompanying drawing:
See Fig. 1, the heat treatment process of thick big section Mo ultralow-carbon martensitic steel-casting grain size is refined, using a staged
Normalizing process is kept the temperature, specifically includes the following steps:
1) it heats up: workpiece being heated to 600-700 DEG C with≤70 DEG C/h heating rate, keeps the temperature 2-6 hours；
2) continue to be heated to 1000-1100 DEG C of solid solution temperature with 70~100 DEG C/h heating rate, heat preservation；
3) temperature is dropped to 800-950 DEG C with the speed of 70~100 DEG C/h again, heat preservation；
4) it is then rapidly heated with the speed of 80~120 DEG C/h to 900-1000 DEG C, is kept the temperature；
5) cooling: using misting cooling to 500 DEG C hereinafter, then proceeding to air-cooled to 300 DEG C hereinafter, continuing to be air-cooled to 100
DEG C or less；
6) it is tempered: 590-650 DEG C of section high tempering 14h being warming up to the speed of≤70 DEG C/h, stablizes the property of steel-casting
Energy.
Above-mentioned steps 2) in soaking time press 25~50mm/h of casting section thickness heat preservation.
Above-mentioned steps 3) in soaking time be 6-10 hour, above-mentioned steps 4) in soaking time be 4-8 hours.
The present invention is kept the temperature by the constant temperature of high-temperature region, can be opened the Dendritic TiC generated in casting process, be made alloying element
Sufficiently it is dissolved into austenitic matrix；Low-temperature insulation after cooling can effectively inhibit growing up for crystal grain, while extend steel
The diffusion time of middle each element reaches uniformly, so as to improve the isotropism of steel-casting, reaches refinement crystal grain, increases
The purpose of strong mechanical performance.
Embodiment 1:
See Fig. 2, hydroelectric blades, material ZG04Cr13Ni5Mo.Belong to axial blade, spindle nose flange thickest
600mm.Normalizing process is kept the temperature using a staged, specifically includes the following steps:
1) heat treatment process card is made according to the structure of practical casting, wall thickness；
2) water of steel-casting, riser are cut off, and after the completion of sand removal processing, is packed into heat treatment furnace；
3) heat treatment normalizing curve is set according to technique card request；
4) service performance for detecting stove must meet the needs of heat treatment cycle curve；
5) 4 hours are kept the temperature with≤70 DEG C/h speed heating heating furnace to 600-700 DEG C according to the requirement of normalizing curve；
6) continue with 95-100 DEG C/h heating rate to be heated to 1040 DEG C of solid solution temperature, according to casting branch can be interrupted
The time of shape crystalline substance keeps the temperature 16h；
7) with the speed of 95-100 DEG C/h, furnace is cold to cool to 820 DEG C, continues low-temperature insulation 8h；
8) it is then rapidly heated with the speed of 110-120 DEG C/h to 980 DEG C of heat preservation 4h；
9) misting cooling is come out of the stove to 500 DEG C hereinafter, stopping spraying；
10) continue air-cooled to 300 DEG C hereinafter, stopping blowing；
11) air-cooled to 70 DEG C or less；
12) it is tempered: 615 DEG C of high tempering 14h being warming up to the speed of≤70 DEG C/h, stablize the performance of steel-casting.
As shown in figs. 3 and 5, use the grain size of the obtained embodiment 1 of heat treatment process of the invention for 4-4.5 grades,
Identical casting uses normative heat treatment technique (as shown in Figure 4), and obtained grain size is 0-0.5 grades.Improving normalizing process
Afterwards, the grain size of casting is significantly improved, so that the performance of casting has very big improvement, can be visited with complete fulfillment
Wound requires.
Original high-temperature region constant temperature normalizing is being changed to the heat preservation of cooling step just by improving normalizing process by examples detailed above
Fire inhibits low crystal grain to grow up, to effectively raise the uniform of tissue on the basis of guaranteeing that alloying element is sufficiently dissolved
Change, improves the fine and smooth degree of crystal grain, improve casting mixed crystal state, enhance the mechanical performance of workpiece.It eliminates and moves back completely
Fire reduces normalizing number, and then reduces energy consumption, reduces costs, shortens the production cycle, improves work efficiency.
Example discussed above is only the practical preferable embodiment of the present invention, but protection scope of the present invention is not limited to
It is any to be familiar with those skilled in the art in the technical scope disclosed by the present invention with this, according to the technique and scheme of the present invention and
Its inventive concept is subject to equivalent substitution or change, is all included within the scope of the present invention.
Claims (3)
1. the heat treatment process of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement, which is characterized in that use a rank
Ladder type keeps the temperature normalizing process, specifically includes the following steps:
1) it heats up: workpiece being heated to 600-700 DEG C with≤70 DEG C/h heating rate, keeps the temperature 2-6 hours；
2) continue to be heated to 1000-1100 DEG C of solid solution temperature with 70~100 DEG C/h heating rate, heat preservation；
3) temperature is dropped to 800-950 DEG C with the speed of 70~100 DEG C/h again, heat preservation；
4) it is then rapidly heated with the speed of 80~120 DEG C/h to 900-1000 DEG C, is kept the temperature；
5) cooling: use misting cooling to 500 DEG C hereinafter, then proceed to it is air-cooled to 300 DEG C hereinafter, continue to be air-cooled to 100 DEG C with
Under.
2. the heat treatment process of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement according to claim 1,
Be characterized in that, above-mentioned steps 2) in soaking time press 25~50mm/h of casting section thickness heat preservation.
3. the heat treatment process of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement according to claim 1,
Be characterized in that, above-mentioned steps 3) in soaking time be 6-10 hour, above-mentioned steps 4) in soaking time be 4-8 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910811630.XA CN110484703B (en) | 2019-08-30 | 2019-08-30 | Heat treatment process for refining grain size of thick large-section ultra-low carbon martensite steel casting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910811630.XA CN110484703B (en) | 2019-08-30 | 2019-08-30 | Heat treatment process for refining grain size of thick large-section ultra-low carbon martensite steel casting |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110484703A true CN110484703A (en) | 2019-11-22 |
| CN110484703B CN110484703B (en) | 2021-04-13 |
Family
ID=68555311
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910811630.XA Active CN110484703B (en) | 2019-08-30 | 2019-08-30 | Heat treatment process for refining grain size of thick large-section ultra-low carbon martensite steel casting |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110484703B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0719869B1 (en) * | 1994-12-26 | 2001-10-17 | The Japan Steel Works, Ltd. | Process for producing high- and low-pressure integral-type turbine rotor |
| CN101629232A (en) * | 2008-07-16 | 2010-01-20 | 上海重型机器冶铸厂 | Heat treatment method for supercritical turbine cylinder steel castings |
| CN103343212A (en) * | 2013-06-27 | 2013-10-09 | 洛阳中创重型机械有限公司 | Heat treatment process after forging of ultra-heavy tube plate forgings splicing-welded in pressure container |
| JP2015000992A (en) * | 2013-06-13 | 2015-01-05 | 独立行政法人日本原子力研究開発機構 | Oxide dispersion strengthened tempered martensitic steel having excellent corrosion resistance, toughness and high-temperature mechanical properties and method of producing the same |
| CN106119469A (en) * | 2016-06-30 | 2016-11-16 | 山东伊莱特重工股份有限公司 | A kind of Technology for Heating Processing of large forgings crystal grain thinning |
| CN109266816A (en) * | 2018-10-18 | 2019-01-25 | 本钢板材股份有限公司 | A kind of oil drill rocker crossover sub and the method for improving its transverse impact toughness |
| CN109576456A (en) * | 2019-01-18 | 2019-04-05 | 辽宁福鞍重工股份有限公司 | A kind of heat treatment process refining large-scale steel-casting grain size |
-
2019
- 2019-08-30 CN CN201910811630.XA patent/CN110484703B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0719869B1 (en) * | 1994-12-26 | 2001-10-17 | The Japan Steel Works, Ltd. | Process for producing high- and low-pressure integral-type turbine rotor |
| CN101629232A (en) * | 2008-07-16 | 2010-01-20 | 上海重型机器冶铸厂 | Heat treatment method for supercritical turbine cylinder steel castings |
| JP2015000992A (en) * | 2013-06-13 | 2015-01-05 | 独立行政法人日本原子力研究開発機構 | Oxide dispersion strengthened tempered martensitic steel having excellent corrosion resistance, toughness and high-temperature mechanical properties and method of producing the same |
| CN103343212A (en) * | 2013-06-27 | 2013-10-09 | 洛阳中创重型机械有限公司 | Heat treatment process after forging of ultra-heavy tube plate forgings splicing-welded in pressure container |
| CN106119469A (en) * | 2016-06-30 | 2016-11-16 | 山东伊莱特重工股份有限公司 | A kind of Technology for Heating Processing of large forgings crystal grain thinning |
| CN109266816A (en) * | 2018-10-18 | 2019-01-25 | 本钢板材股份有限公司 | A kind of oil drill rocker crossover sub and the method for improving its transverse impact toughness |
| CN109576456A (en) * | 2019-01-18 | 2019-04-05 | 辽宁福鞍重工股份有限公司 | A kind of heat treatment process refining large-scale steel-casting grain size |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110484703B (en) | 2021-04-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101805824B (en) | Interrupted quenching thermal treatment method of 42CrMo4 roller shaft | |
| CN103266212A (en) | Thermal treatment technology for improving low-temperature impact toughness of 25Cr2Ni4MoV steel forging | |
| CN105886717B (en) | A kind of residual forging heat normalizing method of steel | |
| CN103361585A (en) | Homogenization treatment process of high-alloying GH742 high temperature alloy | |
| CN102690940A (en) | Technological method for heat treatment of stainless steel bearing | |
| CN106637013A (en) | Thermal treatment method capable of enhancing high temperature strength of Ti2AlNb-based alloy | |
| CN102776335A (en) | Process for manufacturing 17-4PH Martensite precipitation-hardening stainless steel forgings | |
| CN106086361A (en) | A kind of Industrial Steam Turbine Rotors Aided forging piecewise heat treatment method | |
| CN103014299A (en) | Electric impulse treatment method for improving heat treatment efficiency and structure quality of high-speed steel roll | |
| CN106086381A (en) | A kind of rolling deformation hot cold treatment method of lift shaft carrier ring performance | |
| CN103397151B (en) | Special quenching agent for large shaft and preparation method of quenching agent | |
| CN104263885A (en) | Heat treatment process for improving low-temperature toughness of castings | |
| CN110484703A (en) | The heat treatment process of the thick big section Mo ultralow-carbon martensitic steel-casting grain size of refinement | |
| CN102220459B (en) | Heat process capable of lowering ductile-brittle transition temperature and intergranular fracture ratio of turbine blades | |
| CN110079753A (en) | A kind of forging method for eliminating TiAl alloy remnants lamella | |
| CN111100976A (en) | Heat treatment process for preventing cracking of steel for glass mold after forging | |
| CN101982549B (en) | Heat treatment process for ASDO clamp products | |
| CN102417969B (en) | Heat treatment process for high-hardenability Martensitic stainless steel for moving blades | |
| CN1330779C (en) | Heat treating trimming method for large-scale bearing ring | |
| CN101368227A (en) | Thermal treatment method for nuclear in-pile component | |
| CN103343280B (en) | Low-temperature quenching method for medium-carbon steel workpiece | |
| CN112280960A (en) | Heat treatment process for improving grain size of B50A789G blade steel | |
| CN101280353A (en) | Hardness heat treatment quenching process for center of steel ball specifically for wind generating equipment | |
| CN101705346B (en) | Heat treatment method for improving hardness of ZG270-500 eccentric body | |
| CN108384936A (en) | A kind of processing technology of wind turbine gearbox carburizing steel heat treatment after forging |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |