CN114807783A - Iron-based shape memory alloy for stainless steel pipe joint at specific temperature and preparation method thereof - Google Patents

Iron-based shape memory alloy for stainless steel pipe joint at specific temperature and preparation method thereof Download PDF

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CN114807783A
CN114807783A CN202210533702.0A CN202210533702A CN114807783A CN 114807783 A CN114807783 A CN 114807783A CN 202210533702 A CN202210533702 A CN 202210533702A CN 114807783 A CN114807783 A CN 114807783A
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alloy
shape memory
iron
temperature
pipe joint
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CN114807783B (en
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何国球
刘晓山
黄子傲
赖漾
樊康乐
易飞猛
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Pailaifu Shaoxing Memory Alloy New Material Technology Co ltd
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    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/58Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23PMETAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P15/00Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/26Methods of annealing
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D6/00Heat treatment of ferrous alloys
    • C21D6/004Heat treatment of ferrous alloys containing Cr and Ni
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D6/00Heat treatment of ferrous alloys
    • C21D6/005Heat treatment of ferrous alloys containing Mn
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D6/00Heat treatment of ferrous alloys
    • C21D6/008Heat treatment of ferrous alloys containing Si
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/005Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/02Ferrous alloys, e.g. steel alloys containing silicon
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/06Ferrous alloys, e.g. steel alloys containing aluminium

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Abstract

The invention relates to the technical field of memory alloys, in particular to a preparation method of an iron-based shape memory alloy for a stainless steel pipe joint at a specific temperature, which comprises the following steps of (1) ingot casting: after the alloy is prepared, melting the alloy in a high-frequency induction furnace, and when the temperature of the alloy reaches 1500 ℃, slagging off and casting the alloy into a cast ingot; (2) annealing: placing the cast ingot into a box-type resistance furnace for carrying out homogenization annealing at the annealing temperature of 1200 ℃ for 1 h; (3) molding: the annealed casting was rolled into a round bar shape and hot extruded at 800 ℃ to prepare a tubular sample, which was then subjected to a thermo-mechanical treatment. The shape memory alloy with good shape memory effect can be obtained by the method, and the prepared shape memory alloy can be used as a connecting part for connecting various pipelines, and the pipelines are connected by using the shape memory alloy without welding, thereby avoiding the problems of delayed fracture and stress corrosion of welding seams.

Description

Iron-based shape memory alloy for stainless steel pipe joint at specific temperature and preparation method thereof
Technical Field
The invention relates to the technical field of memory alloys, in particular to a preparation method of an iron-based shape memory alloy for a stainless steel pipe joint at a specific temperature.
Background
Shape memory materials are a new type of functional materials that have been developed in recent decades and which possess a unique shape memory effect. The Fe-based memory alloy is a third-generation shape memory material developed after Ti-Ni memory alloy and Cu-based memory alloy, and compared with the former two, the Fe-based memory alloy has the characteristics of low raw material cost, easiness in processing and manufacturing, convenience in normal-temperature transportation, excellent mechanical property and the like, is widely applied to industries such as petroleum machinery and chemical engineering and becomes a research hotspot at present. The Fe-based shape memory alloy mainly includes Fe-Mn-Co-Ti system, Fe-Pt system Fe-Pd system, Fe-Mn-Si system, Fe-Ni-C system. Among them, Fe-Mn-Si alloys have a good shape memory effect and good workability, and are considered to be the most promising. The Fe-Mn-Si alloy has been studied for almost ten years, and although the most advanced alloy has been developed, it is an immature material which can be used for disposable shape memory parts such as pipe joints. The research results in recent years show that the alloy can achieve less than 2% of complete recovery strain. If the pre-strain is more than 2%, the residual strain rate after recovery is increased along with the increase of the pre-strain amount, and shape memory incompleteness generally exists. Therefore, the main goal at present is to optimize the alloy composition and improve the shape memory recovery rate as much as possible. The invention aims to guide the application of the iron-based shape memory alloy in production by researching the influence of alloy components on the iron-based shape memory alloy.
In order to solve the problems, the scheme is developed accordingly.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a preparation method of an iron-based shape memory alloy for a stainless steel pipe joint at a specific temperature, which solves the problems in the background art.
(II) technical scheme
1. In order to achieve the purpose, the invention is realized by the following technical scheme: a preparation method of an iron-based shape memory alloy for a stainless steel pipe joint at a specific temperature comprises the following elements in percentage by mass:
Figure BDA0003647037620000021
preferably, the rare earth additive is 0.2% of Nb, 0.1% of Y, 0.1% of Ce and 0.1% of Tb.
The preparation method of the iron-based shape memory alloy for the stainless steel pipe joint at the specific temperature comprises the following steps:
(1) ingot casting: after the alloy is prepared, melting the alloy in a high-frequency induction furnace, and when the temperature of the alloy reaches 1500 ℃, slagging off and casting the alloy into a cast ingot;
(2) annealing: placing the cast ingot into a box-type resistance furnace for carrying out homogenization annealing at the annealing temperature of 1200 ℃ for 1 h;
(3) molding: the annealed casting was rolled into a round bar shape and hot extruded at 800 ℃ to prepare a tubular sample, which was then subjected to a thermo-mechanical treatment. Finally, the shape memory recovery rate of the prepared sample is measured by using a hole expanding method.
The further thermal-mechanical treatment method in the preparation method of the iron-based shape memory alloy comprises the following steps: and (3) reaming the sample at normal temperature to increase the perimeter by 4-5%, removing the load, then annealing at 600 ℃, wherein the treatment time is 10min, then rapidly cooling to room temperature, repeating for 2-4 times, and processing into the pipe joint.
And expanding the pipe to the required diameter at normal temperature, and cutting the pipe into the required length. When the pipeline is connected, the pipeline does not need to be processed at all, the pipeline joint is heated to 80-90 ℃, and the pipeline joint can be uniformly heated by using the resistor in the installation process, so that the pipeline connection can be completed.
The alloy has shape memory effect, and can generate martensite phase transformation reverse transformation process in the heating recovery process, thereby playing the function of shrinking shape in macroscopic view and being used for connecting pipelines of pipe joints.
The following description of the operation of the alloys involved, is as follows:
1. the function of Mn element in the alloy is as follows: when the Mn content is too low (< 25%), the bcc structure of the alloy is too stable to satisfy the martensite reorientation and martensite reversion processes. When the content of Mn is too high (> 42%), the γ phase is too stable and also not conducive to the martensitic transformation process. Therefore, the content of Mn element in the alloy is 24-32%.
2. The function of Si element in the alloy: the role of Si is mainly three, one is to lower the transition temperature of the antiferromagnet state of the gamma phase: secondly, the strengthened gamma phase makes the alloy not easy to generate permanent slippage when being deformed, thereby improving the shape memory effect of the alloy; thirdly, the gamma phase stacking fault energy is reduced, and the martensite transformation is facilitated. When the content of Si is more than 6%, the mechanical properties of the alloy are deteriorated, and therefore the content of Si element in the alloy is about 5%.
3. The effect of Cr and Ni elements in the alloy is as follows: Fe-Mn-Si memory alloy has a high shape memory effect, but has poor processing and forming capabilities. The processing performance and the corrosion resistance can be effectively improved by adding Cr. The addition of Cr can reduce the Neel temperature TN without adverse effect on the shape memory effect of the alloy, and simultaneously, the addition of Cr lowers the Ms point of the alloy, so that the content of Mn is properly reduced after the addition of Cr so as to maintain the Ms point to be near the room temperature, but when w (Cr) exceeds 7%, a brittle lambda phase is easily generated, and the plasticity of the alloy is reduced. In order to inhibit the generation of the lambda phase, Ni is added into the alloy at the same time for reasonable collocation. Thus, on one hand, the shape memory effect of the alloy can be maintained and even improved, and on the other hand, the corrosion resistance and the processing performance of the alloy can be greatly improved.
4. The function of Al element in the alloy is as follows: the role of aluminium in steel is mainly: (1) deoxidizer in steel making, refined crystal grains, inhibited aging of low-carbon steel and improved toughness of the steel at low temperature; (2) the oxidation resistance of the steel is improved, the performance of the steel is improved, and the corrosion resistance of the steel is improved. The effect reaches saturation at about 1 percent; (3) the As point of the alloy is changed.
5. The effect of rare earth elements in the alloy is as follows: the addition of the composite rare earth additive can obviously improve the shape memory recovery rate of the alloy. The strengthening of the matrix reduces permanent unrecoverable slippage upon initial deformation, which contributes to an increase in shape memory recovery. The alloy added with the composite rare earth additive has a higher fault probability than the alloy without the composite rare earth additive, and has more nucleation centers and smaller strain driving force in the process of strain-induced martensite, so that recoverable martensite is more easily formed.
(III) advantageous effects
After adopting the technical scheme, compared with the prior art, the invention has the following advantages: the invention relates to a preparation method of an iron-based shape memory alloy for a stainless steel pipe joint at a specific temperature, which can obtain the shape memory alloy with good shape memory effect, and the prepared shape memory alloy can be used as a connecting part for connecting various pipelines, and the pipelines are connected by using the shape memory alloy without welding, thereby avoiding the problems of delayed fracture and stress corrosion of welding seams.
Drawings
Fig. 1 is a schematic perspective sectional view of the structure of the pipe joint according to the present invention.
FIG. 2 photograph of the alloy substrate of example 1
FIG. 3 Structure of metallographic structure under optical microscope in example 1
FIG. 4X-ray diffraction Pattern of example 1
FIG. 5 example 1 determination of the phase transition temperature Point of an alloy Using differential scanning calorimetry
Detailed Description
The core of the invention discloses a formula and a preparation method of an iron-based shape memory alloy for a stainless steel pipe joint at a specific temperature, which comprises the following steps: the alloy containing Mn, Si, Ni, Cr, Al, rare earth additive and iron is prepared according to a certain mass percentage, then the alloy is melted in a high-frequency induction furnace, and when the temperature reaches 1500 ℃, the alloy is subjected to slagging-off and then cast into cast ingots. And (2) placing the cast ingot into a box-type resistance furnace for carrying out homogenization annealing, forging the annealed casting, carrying out hot rolling at 800 ℃ to prepare a tubular sample, then carrying out thermal mechanical treatment on the sample, and finally measuring the shape memory recovery rate of the prepared sample by using a hole expansion method. After the annealing treatment, the alloy is subjected to special thermomechanical circulation treatment so as to improve the shape memory effect of the alloy. The element formula in the alloy is uniquely adjusted, so that the memory alloy pipe joint can carry out phase change at a set temperature, and can be used for connecting various pipelines without welding, and the problems of delayed fracture and stress corrosion of a welding line are avoided.
The principle of the technical solution of the present invention is further elaborated by the following specific examples.
Example 1:
the alloy is prepared from Mn28 wt%, Si6 wt%, Ni3 wt%, Cr7 wt%, Al1 wt%, rare earth elements Nb0.2wt%, Y0.1wt%, Ce0.1wt%, Tb0.1wt% and the balance of iron. After the alloy is prepared, the alloy is melted in a high-frequency induction furnace, and when the temperature of the alloy reaches 1500 ℃, the alloy is subjected to slagging-off and then is cast into an ingot. And (3) putting the cast ingot into a box-type resistance furnace for carrying out homogenization annealing at the annealing temperature of 1200 ℃ for 1 h. The annealed castings were forged and hot rolled at 800 ℃ to form tubular test pieces, which were then subjected to thermomechanical treatment.
When the strain of the treated memory alloy pipe joint is 5%, the recovery rate can reach 60%.
Example 2:
the alloy is prepared from Mn24 wt%, Si3 wt%, Ni4 wt%, Cr9 wt%, Al1 wt%, rare earth elements, Y0.1wt%, Tb0.1wt% and the balance of iron. After the alloy is prepared, the alloy is melted in a high-frequency induction furnace, and when the temperature of the alloy reaches 1500 ℃, the alloy is subjected to slagging-off and then is cast into an ingot. And (3) putting the cast ingot into a box-type resistance furnace for carrying out homogenization annealing at the annealing temperature of 1200 ℃ for 1 h. The annealed castings were forged and hot rolled at 800 ℃ to form tubular test pieces, which were then subjected to thermomechanical treatment. The further thermal-mechanical treatment method in the preparation method of the iron-based shape memory alloy comprises the following steps: and (3) reaming the sample at normal temperature to increase the perimeter by 4-5%, removing the load, then annealing at 600 ℃, wherein the treatment time is 10min, then rapidly cooling to room temperature, repeating for 2-4 times, and processing into the pipe joint.
When the strain of the treated memory alloy pipe joint is 5%, the recovery rate can reach 52%.
Example 3:
preparing alloy Mn32 wt%, Si6 wt%, Ni5 wt%, Cr5 wt%, Al1 wt%, rare earth elements Nb0.2wt%, Y0.1wt%, Ce0.1wt%, Tb0.1wt%, and the balance of iron. After the alloy is prepared, the alloy is melted in a high-frequency induction furnace, and when the temperature of the alloy reaches 1500 ℃, the alloy is subjected to slagging-off and then is cast into an ingot. And (3) putting the cast ingot into a box-type resistance furnace for carrying out homogenization annealing at the annealing temperature of 1200 ℃ for 1 h. The annealed castings were forged and hot rolled at 800 ℃ to form tubular test pieces, which were then subjected to thermomechanical treatment. The further thermal-mechanical treatment method in the preparation method of the iron-based shape memory alloy comprises the following steps: and (3) reaming the sample at normal temperature to increase the perimeter by 4-5%, removing the load, then annealing at 600 ℃, wherein the treatment time is 10min, then rapidly cooling to room temperature, repeating for 2-4 times, and processing into the pipe joint.
When the strain of the memory alloy pipe joint obtained by processing is 5%, the recovery rate can reach 53%.
TABLE 1 composition, memory, mechanical Properties of the alloys tested
Figure BDA0003647037620000051
Figure BDA0003647037620000061
Innovation point and mechanism analysis & experimental data analysis:
one, innovation point
1. Designing components: according to the technical scheme, a certain amount of alloy elements and rare earth elements are added while the components are innovative, the alloy elements can improve the poor processing performance of the Fe-Mn-Si alloy, and the rare earth elements can greatly improve the memory performance of the memory alloy.
By reasonably designing the alloy components, the shape memory effect of the alloy is improved. Cr and Ni elements can improve the shape memory effect of the alloy, and also improve the corrosion resistance and the processing performance. The Al element serves to lower the transformation temperature point of the alloy. The addition of rare earth elements can obviously improve the shape memory recovery rate of the alloy.
2. And (3) thermo-mechanical training: the technical scheme of the invention is innovated in the heat treatment process of the pipe joint, and the manufactured pipe joint is subjected to thermal mechanical treatment by using a hole expanding method under specific conditions, so that the shape memory performance of the Fe-based memory alloy can be improved.
The memory alloy pipe joint adopts a special thermomechanical training treatment process, adopts thermomechanical training under the following parameters, can effectively improve the shape memory effect of the alloy, and has the following specific application flow:
1) under normal temperature, the sample is reamed (under load), so that the circumferential length of the sample along the radial direction is increased by 4-5%.
2) After the load is removed, annealing the alloy pipe joint in a resistance furnace, wherein the annealing parameters are as follows: the annealing temperature is 600 ℃, the heat preservation time is 10min, and the sample feeding mode is to enter the furnace at the temperature. And after the heat preservation time is finished, taking out the alloy pipe joint sample, and cooling to room temperature. After the process is repeated for 4 times, the alloy pipe joint obtains the highest recovery rate. Wherein, the temperature, the processing time and the training times of the training process are necessary technical characteristics.
3. Determination of phase transition temperature point: the technical scheme of the invention makes innovation aiming at the final installation and recovery of the alloy pipeline, the alloy pipe joint can generate phase change at about 100 ℃ (80-100 ℃), and the installation of the pipe joint can be completed at the lower temperature.
Second, experimental related data
1. Example 1 preparation of an alloy matrix, resulting in an ingot with dimensions of Φ 90m × 90mm and a weight of 18KG, is shown in fig. 2.
2. Determination of tissue structure
(1) The metallographic structure of the microstructure under the optical microscope of example 1 during the thermomechanical training process, a significant formation of epsilon martensite was observed, as shown in fig. 3: the lath-shaped lines crossing the whole crystal grains are the epsilon martensite phase. The transformation and reversion of the epsilon martensite phase to the austenite gamma parent phase can occur along with the increase and decrease of the temperature, and the epsilon martensite phase is the basis and the key of the shape memory of the alloy.
(2) Three main gamma parent phase peaks and one epsilon martensite peak can be observed in the XRD pattern shown in figure 4, which confirms that epsilon martensite exists in the alloy matrix, namely, epsilon martensite is generated in the alloy during the process of thermal mechanical training, and gamma → epsilon martensite transformation occurs.
Explanation: before training, the alloy matrix is an austenite parent phase, and an epsilon martensite phase does not exist.
3. The phase transition temperature point was determined using a differential scanning calorimeter to determine the phase transition temperature point of the alloy, which was about 100 deg.C, and the test system of example 1 is plotted, as shown in FIG. 5.
4. Method for measuring recovery rate:
the shape memory effect of the shape memory alloy pipe joint adopts the relative strain recovery rate f sme And absolute strain recovery ε a To indicate. Relative strain recovery f sme Absolute strain recovery amount ε a And a pre-deformation amount epsilon p The calculation expression of (a) is as follows:
f sme =[(D 1 -D 2 )/(D 1 -D 0 )]×100%
ε a =D 1 -D 2
ε p =(D 1 -D 0 )/D 0 ×100%
in the formula: d 0 Pipe joint inner diameter before reaming
D 1 Pipe joint inner diameter after reaming
D 2 -pipe joint heat treated annealed inside diameter
5. Relevant experimental data in part for the various examples:
in example 1, the recovery rate of the memory alloy pipe joint changes with the training times when the strain is 5%
Figure BDA0003647037620000081
In example 2, when the strain of the memory alloy pipe joint is 5%, the recovery rate changes along with the change of training times
Figure BDA0003647037620000082
In example 3, the memory alloy pipe joint has a recovery rate varying with the training times when the strain is 5%
Figure BDA0003647037620000083
Figure BDA0003647037620000091
In light of the foregoing, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and the protection scope must be determined by the scope of the claims.

Claims (6)

1. An iron-based shape memory alloy for stainless steel pipe joints at a specific temperature, characterized by: the iron-based shape memory alloy comprises Mn, Si, Ni, Cr, Al, rare earth additive and iron, and the mass percentages of the elements are as follows:
Figure FDA0003647037610000011
the balance being iron.
2. An iron-based shape memory alloy for stainless steel pipe joints at specific temperatures according to claim 1, wherein: the rare earth additive comprises any one or more of Nb, Y, Ce and/or Tb.
3. The method for preparing an iron-based shape memory alloy for stainless steel pipe joints at specific temperatures according to claim 1, wherein: the method comprises the following steps:
(1) ingot casting: after the alloy is prepared, melting the alloy in a high-frequency induction furnace, and when the temperature of the alloy reaches 1500 ℃, slagging off and casting the alloy into a cast ingot;
(2) annealing: placing the cast ingot into a box-type resistance furnace for carrying out homogenization annealing at the annealing temperature of 1200 ℃ for 1 h;
(3) molding: the annealed casting was rolled into a round bar shape and hot extruded at 800 ℃ to prepare a tubular sample, which was then subjected to a thermo-mechanical treatment.
4. A method of manufacturing an iron-based shape memory alloy for stainless steel pipe joints at specific temperatures according to claim 3, wherein: the thermomechanical treatment method specifically comprises the following steps: reaming a sample at the normal temperature of 20 ℃ (by adopting a reaming process commonly used in the field) to increase the perimeter of the sample by 4% -5%, removing load, then annealing at the temperature of 600 ℃, wherein the treatment time is 10min, and then rapidly cooling to the room temperature of 25 ℃; and repeating the processes of reaming, annealing and cooling for 2-4 times to process the pipe joint.
5. The method of claim 4, wherein the application of the iron-based shape memory alloy for stainless steel pipe joints at specific temperatures comprises: the installation method of the pipe joint comprises the following steps: expanding the pipe joint to a required diameter at the normal temperature of 20 ℃, cutting the pipe joint into required lengths, heating the pipe joint to 80-90 ℃, and uniformly heating the pipe joint by using a resistor in the installation process to complete the pipe connection.
6. The special working temperature pipe joint obtained by the manufacturing method of claim 5, characterized in that: the recovery temperature is 80-100 ℃.
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4780154A (en) * 1984-09-07 1988-10-25 Nippon Steel Corporation Shape memory alloy and method for producing same
CN1181425A (en) * 1997-10-20 1998-05-13 河北工业大学 Making method of iron-base marmem pipe joint
CN102796951A (en) * 2012-09-10 2012-11-28 镇江忆诺唯记忆合金有限公司 High ferro-manganese base shape memory alloy
CN103866211A (en) * 2014-03-19 2014-06-18 四川大学 Method of preparing training-free iron-manganese-silicon-based shape memory alloy
CN110983163A (en) * 2019-12-25 2020-04-10 南京龙浩新材料科技有限公司 Method for improving two-way shape memory effect of multi-element iron-based shape memory alloy
CN111235491A (en) * 2019-12-27 2020-06-05 西北工业大学 High-strength high-plasticity shape memory steel and preparation method thereof

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4780154A (en) * 1984-09-07 1988-10-25 Nippon Steel Corporation Shape memory alloy and method for producing same
CN1181425A (en) * 1997-10-20 1998-05-13 河北工业大学 Making method of iron-base marmem pipe joint
CN102796951A (en) * 2012-09-10 2012-11-28 镇江忆诺唯记忆合金有限公司 High ferro-manganese base shape memory alloy
CN103866211A (en) * 2014-03-19 2014-06-18 四川大学 Method of preparing training-free iron-manganese-silicon-based shape memory alloy
CN110983163A (en) * 2019-12-25 2020-04-10 南京龙浩新材料科技有限公司 Method for improving two-way shape memory effect of multi-element iron-based shape memory alloy
CN111235491A (en) * 2019-12-27 2020-06-05 西北工业大学 High-strength high-plasticity shape memory steel and preparation method thereof

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