CN111394657A - Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability - Google Patents

Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability Download PDF

Info

Publication number
CN111394657A
CN111394657A CN202010310491.5A CN202010310491A CN111394657A CN 111394657 A CN111394657 A CN 111394657A CN 202010310491 A CN202010310491 A CN 202010310491A CN 111394657 A CN111394657 A CN 111394657A
Authority
CN
China
Prior art keywords
alloy
phase
core
temperature
less
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.)
Withdrawn
Application number
CN202010310491.5A
Other languages
Chinese (zh)
Inventor
王清
牛犇
董闯
张瑞谦
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dalian University of Technology
Original Assignee
Dalian University of Technology
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Dalian University of Technology filed Critical Dalian University of Technology
Priority to CN202010310491.5A priority Critical patent/CN111394657A/en
Publication of CN111394657A publication Critical patent/CN111394657A/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • 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
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
    • 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
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/04—Making ferrous alloys by melting
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/02—Fuel elements
    • G21C3/04—Constructional details
    • G21C3/06—Casings; Jackets
    • G21C3/07—Casings; Jackets characterised by their material, e.g. alloys
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/004—Dispersions; Precipitations
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—Ferrite
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Metallurgy (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Plasma & Fusion (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Heat Treatment Of Steel (AREA)
  • Heat Treatment Of Sheet Steel (AREA)

Abstract

1200 ℃ short-time high-temperature stable Fe-Cr-Al system with core-shell structure particle precipitationThe ferritic stainless steel belongs to the technical field of new materials, and comprises Fe, Cr, Al, Mo, Nb, Ta and Zr elements, wherein C, Si, Mn, S and P are impurity elements, the mass percentages of alloy components are (wt.%), Cr is 13.0-15.0, Al is 4.0-5.0, Mo is 1.5-3.0, Nb is 0.2-2.0, Ta is 0.5-1.5, Zr is 0.2-0.4, Si is less than or equal to 0.4, C is less than or equal to 0.02, Mn is less than or equal to 0.8, S is less than or equal to 0.035, P is less than or equal to 0.035, and Fe is the balance, the atomic percentage ratio of Cr/(Mo + Nb + Ta + Zr) is 8: 1, the atomic percentage ratio of Mo/(Nb + Ta + Zr) is 2: 1, Nb/Ta + 1: 1, the structural ratio of Ta/Zr is adjusted on the basis, the structural characteristics of the material is that the material is in a crystal boundary at 1200-1200 ℃, and has stable Fe precipitation at a high temperature of L ℃ and has Aves particles23Zr6Particles having a two-phase core-shell structure in which the core is an L aves phase, and Fe23Zr6The fine particles are dispersed on the ferrite matrix, so that the alloy shows excellent structural stability at high temperature, and the high-temperature mechanical property of the alloy is obviously improved.

Description

Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability
Technical Field
The invention belongs to the field of heat-resistant stainless steel materials, and particularly relates to Fe-Cr-Al series ferritic stainless steel with core-shell structure particle precipitation, wherein the precipitated second-phase particles still do not generate a redissolution phenomenon at 1200 ℃/1h, and the excellent high-temperature structure stability is shown, so that the mechanical strength of the alloy at high temperature is ensured, and the Fe-Cr-Al series ferritic stainless steel is expected to be used as an accident-resistant fault-tolerant fuel cladding material of a nuclear reactor, a key structure material of an ultra-supercritical thermal power station and the like.
Background introduction
The fuel cladding material is used as an important structural material in a nuclear power reactor, and the fuel cladding material is under the condition of high temperature and high radiation in the reactor, so higher requirements on performance are put forward. The Zr alloy has good mechanical property, corrosion resistance, machinability, low neutron cross section absorption coefficient and the like, so that the Zr alloy is the most widely applied fuel cladding material in the current nuclear power reactor. The normal service temperature of the Zr alloy cladding material is about 300 ℃, but when a water permeation accident happens, the temperature in the reactor core can be instantly increased to over 1000 ℃, even 1200 ℃, the Zr alloy cladding material is seriously softened at the temperature, and the mechanical property can not meet the performance requirement; meanwhile, Zr element reacts with high-temperature steam to generate a large amount of hydrogen, and when the hydrogen is gathered to a certain amount, explosion is caused, for example, a Japanese Fudao nuclear power station accident happens in 2011. Therefore, it is required to improve the oxidation resistance of the cladding material and meet the mechanical property requirement in the reactor, thereby improving the safety margin of the reactor. In recent years, the requirement of a new generation of accident-resistant and fault-tolerant cladding material is provided, and among the typical cladding candidate materials such as the prior austenitic stainless steel, nickel-based high-temperature alloy, ferritic stainless steel, ferritic/martensitic stainless steel and the like, Fe-Cr-Al series ferritic stainless steel has better high-temperature steam oxidation resistance, corrosion resistance and high-temperature mechanical property than Zr alloy, and simultaneously has good neutron irradiation resistance, so that the Fe-Cr-Al series ferritic stainless steel is expected to become a new generation of cladding candidate material.
The alloy has the mechanical properties of Cr + Cr 2 + Al 2 + Mo + Cr 2 + Cr 2-Al + Cr + Al + Mo + Cr + Al + Cr + Al + Cr + Al + Cr + Al + Cr + Mo, Mo and Mo, Cr + Al + Cr + Al + Cr + Al + Cr + Al + Cr + Al + Cr + Al + Cr +.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides Fe-Cr-Al series ferritic stainless steel with stable 1200 ℃ short-time high-temperature structure and precipitated core-shell structure particles, aiming at designing the ferritic stainless steel with higher structure stability at high temperature by inhibiting coarsening and redissolution of precipitated phase particles at high temperature, and replacing the existing Zr alloy to become a candidate material for reactor cladding by combining with good high-temperature steam oxidation resistance of the ferritic stainless steel. The alloy can precipitate Fe on a ferrite matrix under the conditions of 800 ℃/24h aging and 1050 ℃/1h redissolution reprocessing2M L aves phase and Fe phase23Zr6Phase, both of which strengthen the matrix at high temperatures, and Fe23Zr6In addition to the higher high temperature stability of the L aves phase, there is a precipitated particle with a core-shell structure in which the core is made of Zr-rich Fe23Zr6The phase and the shell are made of L aves phase rich in Mo/Nb/Ta/Zr, and multiple elements are enriched in L aves phase, so that the high-entropy effect is obvious, the stability of the particles at high temperature is further improved, the particles have a core-shell structure, the coarsening and the redissolution of the particles at high temperature can be effectively inhibited, second-phase precipitated particles are uniformly distributed on a ferrite matrix even after the heat preservation is carried out for 1 hour at the high temperature of 1200 ℃, the high-temperature structure stability is excellent, the high-temperature mechanical strength of the alloy at the short time of 1200 ℃ can be ensured, and the novel accident-tolerant fuel cladding material is expected to become a new generation accident-tolerant fuel cladding material.
In order to achieve the purpose, the invention adopts the technical scheme that:
a1200 ℃ short-time high-temperature structure stable Fe-Cr-Al series ferritic stainless steel with core-shell structure particle precipitation comprises Fe, Cr, Al, Mo, Nb, Ta and Zr elements, wherein C, Si, Mn, S and P are impurity elements, the mass percentages (wt.%) of the alloy components are 13.0-15.0 Cr, 4.0-5.0 Al, 1.5-3.0 Mo, 0.2-2.0 Nb, 0.5-1.5 Ta, 0.2-0.4 Zr, 0.4 Si and 0.4, 0.02C, 0.8 Mn, 0.035S, 0.035P, the balance Fe, the atomic percentage ratio of Cr/(Mo + Nb + Ta + Zr) is 8: 1, the atomic percentage ratio of Mo/(Nb + Ta + Zr) is 2: 1, the atomic percentage ratio of Nb + Ta is 1: 1, the grain boundary ratio of Ta (L DEG C) is adjusted on the basis, the Fe-Cr-Nb-Ta-Al series ferritic stainless steel has a high-temperature structure particle precipitation state, and has a high-temperature structure stability at a temperature of the Fe-Ag-Al series stainless steel with the alloy particles precipitation state at L ℃ and the temperature of the alloy particles23Zr6The particles with a double-phase core-shell structure with a core and an L aves phase as a shell are dispersed and distributed on the ferrite matrix, and a large amount of Fe which is finely dispersed and distributed exists on the ferrite matrix after the short-time heat treatment at 1200 ℃/1h23Zr6Phase particles and particles of a dual phase core-shell structure.
Preparation of the inventionThe method comprises the following steps: the component alloy adopts high-purity components, the elements are proportioned according to the mass percent of the alloy components, and the proportioned mixture is smelted for multiple times by using a non-consumable vacuum arc smelting furnace under the protection of Ar gas, so that an alloy ingot with uniform components and the mass of about 100g is obtained. Then carrying out solution treatment on the alloy ingot at the speed of 1200 ℃/2h, and carrying out water quenching; then carrying out multi-pass hot rolling on the alloy ingot in the solid solution state at 800 ℃, wherein the final total deformation is 85-90%, and a plate with the thickness of about 1.5mm is obtained; finally, the alloy plate is subjected to aging treatment at the speed of 800 ℃/24 h. In order to observe the existence of the second phase particles in the aged series alloy at high temperature, the aged sample is respectively kept at 1000 ℃, 1050 ℃, 1100 ℃ and 1200 ℃ for 1h to study the high-temperature structure stability of the series alloy. Using OM, SEM and XRD (Cu K)αλ 0.15406nm) to detect alloy structure and structure; adopting an HVS-1000 Vickers hardness tester to test the microhardness of the series alloy in different processing states; and testing the tensile mechanical properties at room temperature and high temperature by using an MTS universal tensile testing machine. Thus, it was confirmed that the heat-resistant ferritic stainless steel of the present invention has excellent high-temperature structure stability, high-temperature mechanical properties, corrosion resistance and oxidation resistance.
The material organization and performance indexes are as follows: the hardness at 800 ℃/24h aging is HV 260--2The mechanical properties of the aged alloy at high temperature are as follows: at 600 ℃ yield strength σ0.2Not less than 310MPa, tensile strength sigmabMore than or equal to 350MPa and the elongation is more than or equal to 20 percent; sigma at 800 DEG C0.2≥70MPa、σbNot less than 85MPa and not less than 60 percent; sigma at 1050 DEG C0.2≥30MPa、σbNot less than 45MPa and not less than 80 percent; sigma at 1200 deg.C0.2≥15MPa、σbNot less than 20MPa and not less than 100%, and at high temperature above 1050 ℃, in addition to L aves phase precipitation on grain boundary, Fe23Zr6The particles with a double-phase core-shell structure with a core and an L aves phase as a shell are dispersed and distributed on a ferrite matrix, after the short-time heat treatment at 1200 ℃/1h, the tiny L aves phase precipitated on the grain boundary can effectively prevent the growth of matrix grains, and a large amount of tiny Fe dispersed and distributed in the grains23Zr6Phase particles and core-shell structured dual-phase particlesTherefore, the alloy shows excellent structure stability at high temperature, and the mechanical property of the alloy at high temperature is obviously improved.
The existing data show that Fe- (13-15) Cr- (4-5) Al (wt.%) alloy has excellent combination of corrosion resistance and high-temperature steam oxidation resistance, but the defect of high-temperature mechanical property is caused by obvious coarsening of pure BCC ferrite grains at above 800 ℃, after micro-alloying elements such as Mo and Nb are introduced to form L aves phase, the high-temperature mechanical property of the alloy can be obviously enhanced by the dispersion strengthening of L aves phase at high temperature, but L aves phase particles can seriously generate the phenomenon of redissolution at above 1000 ℃ so as to reduce the strengthening effect at high temperature, while the existing strengthening of precipitated phase at high temperature is the strengthening of the precipitated phase by coherent precipitation strengthening of ordered phase gamma' on a gamma matrix in similar nickel-based high-temperature alloy, and the existing hexagonal structure of Fe-Cr-Al alloy is precipitated by particles with a core-shell structure so as to prevent coarsening, so that the high-temperature mechanical property of the alloy is improved2The M-type L aves phase is difficult to be coherent with a BCC ferrite matrix with a cubic structure, so that the coarsening behavior of the particles with the core-shell structure at high temperature can be inhibited from the aspect of precipitation of the particles with the core-shell structure at high temperature23Zr6Even after 1h short-time heat treatment at 1200 ℃, a multi-component L aves phase and finely distributed Fe appear due to the synergistic effect between elements23Zr6The L aves phase can only be preserved to 1000 ℃ in the alloy with only Mo and Nb elements, the applicant finds that the types and the mixture ratio of trace alloying elements in Fe-Cr-Al series stainless steel are crucial to the structure stability of the alloy through a large amount of experimental research, and only the L aves phase with Mo/Nb/Ta enrichment is basically at 1200 ℃ when Zr is not addedThe total re-dissolution is carried out, and the addition of Zr can also obtain Fe with higher stability than that of L aves phase except for L aves phase23Zr6The L aves phase is dispersed and finely distributed in the matrix when the atomic percentage ratio of Cr/(Mo + Nb + Ta + Zr) is 8: 1 and the atomic percentage ratio of Mo/(Nb + Ta + Zr) is 2: 1, if the ratio is higher than the value, a large amount of brittle α' phase is precipitated to deteriorate the alloy performance, so that the element ratio of the alloy is adjusted by Nb, Ta and Zr on the basis of the above, the Nb: Ta is kept at 1: 1, and the ratio of (Nb/Ta) and Zr is adjusted on the basis of the Nb: Ta is kept at 1: 1.
Specifically, the effects of the elements in Fe-Cr-Al ferritic steel are described in the following (1) Cr is a main element for providing corrosion resistance in stainless steel, the Tammann law indicates that when Cr is added into Fe to form a solid solution, the electrode potential changes abruptly (n/8 law) along with the increase of Cr content, namely the electrode potential of the Fe is suddenly and significantly increased when the atomic percentage (at.%) of Cr reaches 12.5% and 25% … and suddenly and significantly weakened when corrosion occurs, the excessively high content of Cr causes the precipitation of a Cr-rich α' phase in a matrix, the mechanical properties of the alloy are reduced, and in order to ensure that the alloy has high corrosion resistance and mechanical properties, the Al content of the invention is 13.0-15.0 wt.% (2) Al is a main element for ensuring that the alloy has excellent high-temperature water vapor oxidation resistance, the higher content of Al is better, but the excessively high content of Al causes the reduction of the processability of the alloy, the Al content of the invention is 4.0-5.0 wt.% (3) Ta) is a main element for ensuring that the alloy has excellent high-temperature water vapor oxidation resistance, the Mo is improved by adding the addition of Mo, the Al content of the Mo is a Mo precipitation of the element, the alloy is also increased by adding the addition of the Mo to form a high-temperature resistance of the Mo, the Mo phase of the Mo, the Al of2The M-type L aves phase can exist at a high temperature of more than 1000 ℃, particularly the L aves phase mainly comprising Zr and Ta can inhibit Mo and Nb elements from being dissolved back into a matrix from the L aves phase, has a remarkable high-entropy effect, and can stably exist at 1200 ℃The applicant finds that when the Nb content is higher than 2.0 wt.%, or the Ta content is higher than 1.5 wt.%, or the Zr content is higher than 0.4 wt.%, the L aves phase precipitated in the matrix has too high content and large particle size, so that the mechanical property of the material is reduced, and the Nb, Ta and Zr contents are respectively 0.2-2.0 wt.% of Nb, 0.5-1.5 wt.% of Ta, 0.2-0.4 wt.% (5) Si/Mn: Si and Mn are taken as impurity elements brought in steel making for deoxidation and desulfurization, but the Si content is too high to promote brittleness3Si and α', the contents need to be controlled to be less than or equal to 0.4 wt% Si, less than or equal to 0.8 wt% Mn, (6) C/S/P, the content of C, S, P, which is a common impurity element in steel, is controlled to be less than or equal to 0.02 wt%, S is less than or equal to 0.035 wt%, and P is less than or equal to 0.035 wt%.
Compared with the prior art, the invention has the advantages that: the present invention precipitates an inner shell made of Zr-rich Fe in Fe-Cr-Al ferritic stainless steel23Zr6In addition, compared with the alloy strengthened by the single L aves phase, the L aves phase formed in the alloy of the application is multi-component co-alloying and shows a high-entropy stabilizing effect brought by high-temperature high configuration entropy, and more importantly, an intermetallic compound Fe with higher thermal stability than the L aves phase is introduced23Zr6Phase, Fe is uniformly distributed on the ferrite matrix even at a high temperature of 1200 DEG C23Zr6The obtained Fe-Cr-Al series ferritic stainless steel has excellent high-temperature structure stability, high-temperature mechanical property, corrosion resistance, high-temperature oxidation resistance and neutron irradiation resistance, and the structure and performance indexes of the material are that the hardness is HV 260℃ and 266Kgf mm at the time of aging at 800 ℃/24h-2The mechanical properties of the aged alloy at high temperature are as follows: at 600 ℃ yield strength σ0.2Not less than 310MPa, tensile strength sigmabMore than or equal to 350MPa and the elongation is more than or equal to 20 percent; sigma at 800 DEG C0.2≥70MPa、σb≥85MPa is greater than or equal to 60 percent; sigma at 1050 DEG C0.2≥30MPa、σbNot less than 45MPa and not less than 80 percent; sigma at 1200 deg.C0.2≥15MPa、σbNot less than 20MPa and not less than 100%, and at high temperature above 1050 ℃, in addition to L aves phase precipitation on grain boundary, Fe23Zr6The particles with a double-phase core-shell structure with a core and an L aves phase as a shell are dispersed and distributed on a ferrite matrix, after the short-time heat treatment at 1200 ℃/1h, the tiny L aves phase precipitated on the grain boundary can effectively prevent the growth of matrix grains, and a large amount of tiny Fe dispersed and distributed in the grains23Zr6The alloy has excellent structure stability at high temperature, and thus the mechanical property of the alloy at high temperature is obviously improved.
The invention has the advantages that ① develops the Fe-Cr-Al series ferritic stainless steel with stable 1200 ℃ short-time high-temperature structure and precipitated core-shell structure particles, the weight percentage (wt.%) of the alloy elements is 13.0-15.0 Cr, 4.0-5.0 Al, 1.5-3.0 Mo, 0.2-2.0 Nb, 0.5-1.5 Ta, 0.2-0.4 Zr, less than or equal to 0.4 Si, less than or equal to 0.02C, less than or equal to 0.8 Mn, less than or equal to 0.035S, less than or equal to 0.035P, and the balance Fe, the basic components are Fe-Cr-Al, the cost is low, the melting and preparation process of ② alloy is simple, and the ③ alloy can have Fe besides L aves phase at the temperature of more than 1000 ℃, and also has Fe23Zr6Separating out two phases which are formed by Fe above 1050 DEG C23Zr6The particles with a double-phase core-shell structure with a core and an L aves phase as a shell can inhibit the coarsening phenomenon of precipitated phase particles at high temperature, greatly improve the tissue stability of the alloy at high temperature, and effectively inhibit the growth of matrix grains by the L aves phase existing on the grain boundary even after the alloy is kept at 1200 ℃ for 1h, and a certain amount of fine Fe is dispersed and distributed in the grains23Zr6The phase and L aves phase particles enable the alloy to have excellent mechanical property, processability, corrosion resistance and high-temperature oxidation resistance at high temperature, can provide larger safety margin for a nuclear reactor in a short time and avoid potential serious core melting accidents, and is expected to be used for a new-generation accident-resistant fuel cladding material.
Drawings
FIG. 1 is a SEM-BSE texture map of the alloy of example 1 after 1050 deg.C/1 h aging;
FIG. 2 is a SEM-BSE texture of the alloy of example 1 after 1200 deg.C/1 h aging;
FIG. 3 is a SEM-BSE texture of the alloy of example 2 after 1200 deg.C/1 h aging.
Detailed Description
The following describes the embodiments of the present invention in detail with reference to the technical solutions.
Example 1: fe78.31Al4.73Cr13.50Mo2.08Nb0.4Ta0.78Zr0.2(wt.％)
The method comprises the following steps: alloy preparation
The component alloy adopts high-purity components, and the elements are proportioned according to the alloy components by mass percent: smelting the proportioned mixture for multiple times by using a non-consumable vacuum arc smelting furnace under the protection of Ar atmosphere to obtain an alloy ingot with uniform components and the mass of about 100g, and then carrying out solution treatment at 1200 ℃/2h on the alloy ingot and water quenching; then carrying out multi-pass hot rolling on the alloy ingot in the solid solution state at 800 ℃, wherein the final deformation is 85-90%, and the thickness of the obtained alloy plate is about 1.5 mm; finally, the alloy plate is subjected to aging treatment at 800 ℃/24 h.
Step two: alloy texture Structure and mechanical Property testing
Using OM, SEM and XRD to detect alloy structure and structure after aging and re-solution treatment, the result shows that the alloy is ferrite matrix with great amount of L aves phase precipitated in the matrix, and using MTS universal tensile testing machine and HVS-1000 Vickers hardness tester to test mechanical performance parameters of the plate sample after aging treatment, wherein the hardness is HV 266Kgf mm after aging at 800 deg.C/24 h-2The mechanical property of the aged alloy at high temperature is that the yield strength sigma is at 600 DEG C0.2358MPa tensile Strength σb377MPa, elongation 20%; sigma at 800 DEG C0.2＝74MPa、σb91MPa and 104%; sigma at 1050 DEG C0.2＝34MPa、σb50MPa and 125%; sigma at 1200 deg.C0.2＝20MPa、σb＝25MPa、＝140％。
Step three: study on structural stability of alloy
In order to study the stability of the alloy structure, re-solution treatment is carried out at different temperatures of 1000 ℃, 1050 ℃, 1100 ℃ and 1200 ℃ for 1h, and the alloy structure and structure after aging and re-solution treatment are detected by using OM, SEM and XRD, and the result shows that at a high temperature of above 1050 ℃, two precipitated phases, namely L aves phase and Fe phase, are distributed on a BCC matrix23Zr6The L aves phase has distribution in both the intragranular and the grain boundary, Fe23Zr6The particles are fine and mainly distributed in the crystal, and an L aves phase wrapping Fe is also found23Zr6The phase formed particles of a core-shell structure are distributed in a large amount on the ferrite matrix, the Fe23Zr6The double-phase core-shell structure particles with the core of L aves phase as the shell prevent the internal Fe23Zr6After 1200 ℃/1h short-time heat treatment, partial re-dissolution is carried out compared with the precipitation phase of the aging alloy, but the fine L aves phase precipitated on the grain boundary can still effectively prevent the growth of matrix grains, and a large amount of fine dispersed Fe exists in the grains23Zr6The phase particles and the core-shell structure dual-phase particles (as shown in fig. 2) enable the alloy to show excellent structural stability at high temperature, so that the mechanical property of the alloy at high temperature is remarkably improved.
Example 2: fe78.36Al4.73Cr13.51Mo2.08Nb0.34Ta0.65Zr0.33(wt.％)
The method comprises the following steps: alloy preparation
Alloy preparation same as step one of example one
Step two: alloy texture Structure and mechanical Property testing
Using OM, SEM and XRD to detect aging + alloy structure and structure after solution treatment, the result shows that the alloy is ferrite matrix with great amount of L aves phase precipitated in the matrix, and using MTS universal tensile testing machine and HVS-1000 Vickers hardness tester to test mechanical property parameters of the plate sample after aging treatment, which are respectively: alloy HV after aging is 262Kgf mm-2(ii) a The mechanical properties of the alloy at high temperature after aging are as follows: at 600 ℃ σ0.2＝312MPa，σb355MPa, 21% at 800 ℃ Sigma0.2＝78MPa，σb85MPa and 91%; sigma at 1050 DEG C0.2＝30MPa、σb45MPa and 80%; sigma at 1200 deg.C0.2＝17MPa、σb＝20MPa、＝130％。
Step three: study on structural stability of alloy
In order to study the stability of the alloy structure, the alloy structure and structure after aging and re-solution treatment are detected by OM, SEM and XRD, and the alloy is a ferrite matrix at 1050 ℃, and a large amount of L aves phase and Fe are precipitated in the matrix23Zr6Phase, simultaneous presence of L aves phase and Fe23Zr6After short-time heat treatment at 1200 ℃/1h, the precipitated phase on the ferrite matrix has a large amount of finely dispersed Fe in the crystal except L aves phase on and in the crystal boundary23Zr6Meanwhile, a L aves phase enriched with Zr, Ta and Nb is also greatly wrapped with Fe23Zr6Two-phase coexisting core-shell structure particles (L aves phase is shell and Fe)23Zr6The phase is the synergistic precipitation of the core) (as shown in figure 3), the structure avoids the re-dissolution of the single-phase L aves phase at high temperature, the high-temperature structure stability of the alloy is obviously increased, and the high-temperature short-time mechanical property of the alloy is improved.
Example 3: fe77.61Al4.00Cr14.97Mo2.30Nb0.23Ta0.5Zr0.39(wt.％)
The method comprises the following steps: alloy preparation
Alloy preparation same as step one of example one
Step two: alloy texture Structure and mechanical Property testing
The alloy structure and structure after aging + solution treatment are detected by using OM, SEM and XRD, and the result shows that the alloy isA ferrite matrix, a large amount of L aves phases are precipitated in the matrix, and the mechanical property parameters of the plate sample after aging treatment are tested by an HVS-1000 Vickers hardness tester, wherein the parameters are respectively that the alloy HV is 264Kgf mm after aging-2(ii) a The mechanical properties of the alloy at high temperature after aging are as follows: at 600 ℃ σ0.2＝320MPa，σb360MPa, 21% at 800 ℃ sigma0.2＝70MPa，σb90MPa, 75%; sigma at 1050 DEG C0.2＝33MPa、σb47MPa and 105%; sigma at 1200 deg.C0.2＝16MPa、σb＝22MPa、＝120％。
Step three: study on structural stability of alloy
In order to research the stability of the alloy structure, the alloy structure and the structure after aging and the re-solution treatment are detected by OM, SEM and XRD, and the alloy is a ferrite matrix at 1050 ℃, and a large amount of L aves phase and Fe are precipitated in the matrix23Zr6Phase, simultaneous presence of L aves phase and Fe23Zr6The two phases are synergistically precipitated, and a large amount of precipitated phases (L aves + Fe) still exist after the short-time heat treatment of 1200 ℃/1h23Zr6) In which Fe is finely dispersed23Zr6The phase is dominant, and core-shell structure particles with two coexisting phases exist at the same time.
Example 4: fe78.04Al4.97Cr13.01Mo1.50Nb0.72Ta1.48Zr0.28(wt.％)
The method comprises the following steps: alloy preparation
Alloy preparation same as step one of example one
Step two: alloy texture Structure and mechanical Property testing
The OM, SEM and XRD are used for detecting the alloy structure and structure after aging and solution treatment, the result shows that the alloy is a ferrite matrix, a large amount of L aves phase is precipitated in the matrix, and an HVS-1000 Vickers hardness tester is used for testing the mechanical property parameters of the plate sample after aging, wherein the alloy HV is 263Kgf mm after aging-2(ii) a After agingThe mechanical properties of the alloy at high temperature are as follows: at 600 ℃ σ0.2＝315MPa，σb360MPa, 24% at 800 ℃ sigma0.2＝73MPa，σb85MPa, 78%; sigma at 1050 DEG C0.2＝30MPa、σb45MPa and 80%; sigma at 1200 deg.C0.2＝15MPa、σb＝20MPa、＝115％。
Step three: study on structural stability of alloy
To study the stability of the alloy structure, it was then subjected to re-solution treatment at 1000 deg.C, 1050 deg.C, 1100 deg.C, 1200 deg.C for 1h, and the aged + re-solution treated alloy structure and structure were examined using OM, SEM and XRD, showing that L aves phase and Fe would be present at high temperature23Zr6Two kinds of particles, wherein Fe23Zr6Is even finer, and simultaneously has L aves phase and Fe23Zr6The core-shell structure particles are formed by phase cooperation and precipitation.
The above-mentioned embodiments only express the embodiments of the present invention, but not should be understood as the limitation of the scope of the invention patent, it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the concept of the present invention, and these all fall into the protection scope of the present invention.

Claims (2)

1. A1200 ℃ short-time high-temperature structure-stable Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation is characterized in that: the Fe-Cr-Al series ferritic stainless steel comprises Fe, Cr, Al, Mo, Nb, Ta and Zr elements, wherein C, Si, Mn, S and P are impurity elements, the mass percentages of alloy components are as follows (wt.%), and Cr: 13.0 to 15.0, Al: 4.0-5.0, Mo: 1.5 to 3.0, Nb: 0.2 to 2.0, Ta: 0.5 to 1.5, Zr: 0.2-0.4, Si is less than or equal to 0.4, C is less than or equal to 0.02, Mn is less than or equal to 0.8, S is less than or equal to 0.035, P is less than or equal to 0.035, Fe: the balance, wherein the atomic percentage ratio of Cr/(Mo + Nb + Ta + Zr) is 8: 1, the atomic percentage ratio of Mo/(Nb + Ta + Zr) is 2: 1, Nb/Ta is 1: 1, and adjusting the ratio of (Nb/Ta) and Zr on the basis of the ratio.
2. The Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability as claimed in claim 1, characterized in that the ferritic stainless steel alloy has a special morphology of precipitated particle structure, wherein at a high temperature of 1050 ℃ or higher, L aves phase particles are precipitated on the matrix grain boundary, and a type of Fe with high-temperature stability and high-temperature stability exists23Zr6The particles with a double-phase core-shell structure with a core and an L aves phase as a shell are dispersed and distributed on the ferrite matrix, and the dispersed and distributed Fe exists on the ferrite matrix after the short-time heat treatment at 1200 ℃/1h23Zr6Phase particles and particles of a dual phase core-shell structure.
CN202010310491.5A 2020-04-20 2020-04-20 Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability Withdrawn CN111394657A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010310491.5A CN111394657A (en) 2020-04-20 2020-04-20 Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010310491.5A CN111394657A (en) 2020-04-20 2020-04-20 Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability

Publications (1)

Publication Number Publication Date
CN111394657A true CN111394657A (en) 2020-07-10

Family

ID=71435546

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010310491.5A Withdrawn CN111394657A (en) 2020-04-20 2020-04-20 Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability

Country Status (1)

Country Link
CN (1) CN111394657A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113667806A (en) * 2021-07-26 2021-11-19 中国科学院金属研究所 Multistage heat treatment method for solving Gd-containing duplex stainless steel hot working cracks

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005206944A (en) * 2003-12-26 2005-08-04 Jfe Steel Kk FERRITIC Cr-CONTAINING STEEL AND ITS PRODUCTION METHOD
CN107723617A (en) * 2017-09-15 2018-02-23 大连理工大学 One kind has the Fe Cr Al base ferritic stainless steels of 1200 °C/1h short time high temperature tissue stabilizations
JP6327077B2 (en) * 2014-04-04 2018-05-23 新日鐵住金株式会社 Austenitic stainless steel
CN108779535A (en) * 2016-04-11 2018-11-09 泰拉能源公司 High temperature, radiation hardness ferrite-martensite steel
CN110195191A (en) * 2019-06-13 2019-09-03 上海大学 Nuclear reactor fuel element cladding materials Fe-Cr-Al alloy and preparation method thereof
CN110863152A (en) * 2019-12-05 2020-03-06 中国核动力研究设计院 Preparation method of FeCrAl-based ODS alloy for nuclear reactor accident-resistant fuel element cladding

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005206944A (en) * 2003-12-26 2005-08-04 Jfe Steel Kk FERRITIC Cr-CONTAINING STEEL AND ITS PRODUCTION METHOD
JP6327077B2 (en) * 2014-04-04 2018-05-23 新日鐵住金株式会社 Austenitic stainless steel
CN108779535A (en) * 2016-04-11 2018-11-09 泰拉能源公司 High temperature, radiation hardness ferrite-martensite steel
CN107723617A (en) * 2017-09-15 2018-02-23 大连理工大学 One kind has the Fe Cr Al base ferritic stainless steels of 1200 °C/1h short time high temperature tissue stabilizations
CN110195191A (en) * 2019-06-13 2019-09-03 上海大学 Nuclear reactor fuel element cladding materials Fe-Cr-Al alloy and preparation method thereof
CN110863152A (en) * 2019-12-05 2020-03-06 中国核动力研究设计院 Preparation method of FeCrAl-based ODS alloy for nuclear reactor accident-resistant fuel element cladding

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
M. WASIM ANJUM ET AL.: "Influence of Ta/Zr minor-alloying on the high-temperature microstructural stability of cladding FeeCreAl ferritic stainless steels", 《JOURNAL OF NUCLEAR MATERIALS》 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113667806A (en) * 2021-07-26 2021-11-19 中国科学院金属研究所 Multistage heat treatment method for solving Gd-containing duplex stainless steel hot working cracks

Similar Documents

Publication Publication Date Title
Chen et al. Effects of Nb-doping on the mechanical properties and high-temperature steam oxidation of annealing FeCrAl fuel cladding alloys
CN103866163B (en) A kind of nickel chromium cobalt molybdenum refractory alloy and tubing manufacturing process thereof
AU2012234641B2 (en) High-strength austenitic stainless steel for high-pressure hydrogen gas
WO2021254028A1 (en) B2 nanoparticle coherent precipitation strengthened ultrahigh-strength maraging stainless steel and preparation method therefor
AU2010291651B2 (en) Method for producing an iron-chromium alloy
Zhang et al. Effects of Cr element on the crystal structure, microstructure, and mechanical properties of FeCrAl alloys
US20240093339A1 (en) High-entropy austenitic stainless steel and preparation method thereof
CN109136652B (en) Nickel-based alloy large-section bar for nuclear power key equipment and manufacturing method thereof
US11242585B2 (en) Iron-based superalloy for high temperature 700 ° C. with coherent precipitation of cuboidal B2 nanoparticles
CN111945063B (en) Steel for high-strength corrosion-resistant fastener for ocean wind power and production method
JP2010037655A (en) Steel superior in hydrogen resistance for vessel for storing high-pressure hydrogen gas therein, and manufacturing method therefor
CN107723617A (en) One kind has the Fe Cr Al base ferritic stainless steels of 1200 °C/1h short time high temperature tissue stabilizations
Anjum et al. Influence of Ta/Zr minor-alloying on the high-temperature microstructural stability of cladding Fe–Cr–Al ferritic stainless steels
CN106381452A (en) Heat resistant austenitic stainless steel with high structure stability at 700 DEG C
JP5769204B2 (en) Fe-Ni base alloy having excellent high temperature characteristics and hydrogen embrittlement resistance and method for producing the same
CN111394657A (en) Fe-Cr-Al ferritic stainless steel with core-shell structure particle precipitation and 1200 ℃ short-time high-temperature structure stability
CN104451260B (en) A kind of nuclear reactor fuel can zirconium-niobium alloy containing ferrimanganic
CN107841657A (en) A kind of high tough Ni Cr Mo base casting alloys
CN105018795B (en) A kind of nuclear reactor fuel can zirconium-base alloy of fine corrosion resistance
CN102586686B (en) Clean corrosion-resistant steel for ocean engineering and manufacturing method thereof
JP5696271B2 (en) Austenitic high-purity iron alloy with excellent high-temperature strength characteristics
CN116240442B (en) Low-activation high-strength multicomponent alloy and preparation method thereof
CN105296803A (en) Zirconium niobium alloy for nuclear reactor fuel cladding and preparation method thereof
CN111826590B (en) Fe23Zr6And Fe2M-Laves phase co-reinforced FeCrAl stainless steel and preparation method thereof
CN102400060A (en) Novel nitrogen-containing austenitic heat-resistant steel

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
WW01 Invention patent application withdrawn after publication

Application publication date: 20200710

WW01 Invention patent application withdrawn after publication