CN114540693A - High-strength, high-toughness and corrosion-resistant Fe-rich Si-containing multi-component alloy and preparation method and application thereof - Google Patents

Abstract

The invention discloses a high-strength, toughness and corrosion-resistant Fe-rich and Si-containing multi-component alloy and a preparation method and application thereof. The Fe-rich and Si-containing multi-component alloy is composed of Fe 27-35%, Ni 17 ～22%, Cr 17～22%, Co 17～22% and Si 3～15%; among them, the sum of the atomic percentages of Fe, Ni, Cr and Co is ≥85%; the atomic percentages of each component The sum is 100%. The Fe-rich and Si-containing multi-component alloy prepared by the invention has the microstructure feature of the face-centered cubic structure as the matrix, shows high strength and plasticity, and has excellent corrosion resistance at the same time; the Fe-rich and Si-containing multi-component alloy can be It is applied to structural components serving in corrosive environments to solve the problems of low strength of corrosion-resistant alloys used in a large number of existing engineering structures.

Description

A kind of high strength, toughness and corrosion resistance of Fe-rich and Si-containing multi-component alloy and its preparation method and application

technical field

The invention belongs to the technical field of metal materials, and in particular relates to a high-strength, toughness-corrosion-resistant Fe-rich and Si-containing multi-component alloy and a preparation method and application thereof.

Background technique

With the development of many fields such as petroleum, chemical industry, national defense, etc., the performance requirements of these engineering structural materials are getting higher and higher, and traditional materials are gradually unable to meet the requirements of some key equipment. Some key engineering equipment materials not only need to have excellent corrosion resistance, but also need to have good mechanical properties, such as good strength and toughness. The development of high-strength and corrosion-resistant structural materials can extend the service life of components, reduce resource consumption, and ensure the safety of engineering components in more severe service environments.

At present, the materials of engineering structural components applied to corrosion-resistant environments are mainly different types of stainless steels, such as 304 and 316 stainless steels, etc., because the higher Cr content (>12wt.%) makes them suitable for most corrosive environments. The formation of a dense passive film is effective against general corrosion, pitting corrosion and stress corrosion cracking, etc., and at the same time shows good plasticity (tensile elongation can be greater than 40%). However, traditional stainless steel has the problem of low strength. Its yield strength is generally below 200MPa, and its tensile strength is generally below 550MPa; and it is also prone to local corrosion in strong corrosive environments, and stress corrosion occurs under high stress. risk of cracking.

In recent years, high-entropy alloys (High-entropy alloys) and multi-component alloys (Multi-componentalloys) break through the traditional alloy design criteria, so they have received extensive attention, such alloys have at least four or five component atomic fractions more than 5%. The characteristics of many alloying elements and their high concentrations often make the alloys have excellent comprehensive properties. For example, CoCrFeMnNi high-entropy alloy with equal atomic ratio has superior fracture toughness, good plasticity, etc.; its fracture toughness value at liquid nitrogen temperature is superior to that of stainless steel, and can be comparable to the existing low-temperature steel [B.Gludovatz, A. Hohenwarter, D. Catoor, E.H. Chang, E.P. George, R.O. Ritchie, Science, 345 (2014) 1153-1158].

However, many high-entropy alloys (or multi-component alloys) with good plasticity such as Co ₂₀ Cr ₂₀ Fe ₂₀ Mn ₂₀ Ni ₂₀ have poor corrosion resistance and poor resistance to chloride ion corrosion. Moreover, its room temperature strength is low, and the yield is generally below 350MPa [F.Otto, A. Dlouhy, Ch. Somsen, H. Bei, G. Eggeler, EP George, Acta Materialia 61 (2013) 5743-5755]. Therefore, the development of high-strength, tough and corrosion-resistant metal structural materials is of great significance for engineering equipment serving under extreme conditions.

SUMMARY OF THE INVENTION

The purpose of this section is to outline some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the application to avoid obscuring the purpose of this section, abstract and title, and such simplifications or omissions may not be used to limit the scope of the invention.

The present invention has been made in view of the above and/or problems existing in the prior art.

One of the objects of the present invention is to provide a high-strength, toughness and corrosion-resistant Fe-rich and Si-containing multi-component alloy. On the basis of the existing Fe-rich multi-component alloy, through the alloying of Si, a corrosion-resistant and relatively strong alloy is provided. The invention discloses a new type of multi-component alloy material with high plasticity and good plasticity and a preparation method, and solves the technical problems of poor corrosion resistance and low strength of some existing multi-component alloys.

In order to solve the above technical problems, the present invention provides the following technical solutions: a high-strength, toughness, corrosion-resistant, Fe-rich and Si-containing multi-component alloy, which is composed of Fe 27-35%, Ni 17-22%, Cr 17～22%, Co 17～22% and Si 3～15%;

Among them, the sum of the atomic percentages of Fe, Ni, Cr, and Co is ≥85%; the sum of the atomic percentages of each component is 100%.

Another object of the present invention is to provide the preparation method of the high-strength, toughness and corrosion-resistant Fe-rich and Si-containing multi-component alloy as described above, including,

Prepare each component by atomic percentage;

Smelting under vacuum or inert gas protection conditions to obtain alloy billets;

After hot rolling, homogenization, cold rolling and annealing treatment of the slab, a multi-component alloy rich in Fe and containing Si is obtained.

As a preferred solution of the preparation method of the high-strength-tough-corrosion-resistant Fe-rich and Si-containing multi-component alloy of the present invention, wherein: the raw materials of each component are prepared, and the raw materials of each component are pure elements or bulk or intermediate alloys. Granules, raw material purity ≥99.50%.

As a preferred solution of the preparation method of the high-strength, toughness and corrosion-resistant Fe-rich and Si-containing multi-component alloy of the present invention, wherein: the smelting under vacuum or inert gas protection conditions, the smelting under vacuum conditions, the vacuum degree is 1～ 0.0001Pa; smelting under inert gas protection conditions, inert gas pressure is 100 ~ 500Pa.

As a preferred solution of the preparation method of the high-strength-tough-corrosion-resistant Fe-rich Si-containing multi-component alloy of the present invention, wherein: in the melting, the melting temperature is 1600-2300°C.

As a preferred solution of the preparation method of the high-strength-tough-corrosion-resistant Fe-rich and Si-containing multi-component alloy of the present invention, wherein: the casting billet is hot-rolled, multi-pass hot-rolling is adopted, and the hot-rolling temperature is 900° C.～1200° C. ℃, the single rolling reduction is less than or equal to 30%, and the total rolling reduction is 50-80%.

As a preferred solution of the preparation method of the high-strength, toughness-corrosion-resistant Fe-rich and Si-containing multi-component alloy of the present invention, wherein: the homogenization temperature is 1100-1200°C, and the treatment time is 30-600 minutes.

As a preferred solution of the preparation method of the high-strength-tough-corrosion-resistant Fe-rich and Si-containing multi-component alloy of the present invention, wherein: the cold rolling adopts multi-pass room temperature cold rolling, and the single pass rolling reduction is less than or equal to 20%, The total rolling reduction is 50 to 90%.

As a preferred solution of the preparation method of the high-strength, toughness and corrosion-resistant Fe-rich and Si-containing multi-component alloy of the present invention, wherein, in the annealing treatment, the annealing temperature is 800-1000° C., and the annealing time is 5-30° C. minute.

Another object of the present invention is to provide the application of the above-mentioned high-strength, toughness, corrosion-resistant Fe-rich and Si-containing multi-component alloy in a corrosive environment. The Fe-rich Si-containing multi-component alloy material prepared by the present invention has a face center The cubic structure is the microstructure characteristic of the matrix, showing high strength and plasticity, as well as excellent corrosion resistance. The passivation current density in 3.5wt.%NaCl solution is between 1.5×10 ^-6 and 2.5×10 ^-6 A/cm ² , and the corrosion potential is between -0.15 and -0.3V _SCE . Multi-component alloys can be used in structural components serving in corrosive environments to solve the problems of low strength of a large number of existing corrosion-resistant alloys for engineering structures.

Compared with the prior art, the present invention has the following beneficial effects:

The Fe-rich and Si-containing multi-component alloy material provided by the invention has the microstructure feature of the face-centered cubic solid solution structure as the matrix, which ensures good plasticity; High yield strength and good work hardening ability make tensile strength also high; at the same time, this kind of alloy has excellent resistance to chloride ion corrosion; its excellent comprehensive properties make it applicable to oceans with high chloride ion concentration in important structural components serving in the environment.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without any creative effort. in:

1 is an XRD pattern of the Fe-rich and Si-containing multi-component alloy material provided in Example 1 of the present invention.

2 is a scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material provided in Example 1 of the present invention.

3 is a room temperature tensile curve of the Fe-rich and Si-containing multi-component alloy material provided in Example 1 of the present invention.

4 is a scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material provided in Example 1 of the present invention soaked in a 3.5 wt.% NaCl solution for 15 days.

FIG. 5 is the electrochemical polarization curve of the Fe-rich and Si-containing multi-component alloy material provided in Example 1 of the present invention in a 3.5 wt.% NaCl solution.

6 is the XRD pattern of the Fe-rich and Si-containing multi-component alloy material provided in Example 2 of the present invention.

7 is a scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material provided in Example 2 of the present invention.

FIG. 8 is the room temperature tensile curve of the Fe-rich and Si-containing multi-component alloy material provided in Example 2 of the present invention.

9 is a scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material provided in Example 2 of the present invention soaked in a 3.5wt.% NaCl solution for 15 days.

10 is the electrochemical polarization curve of the Fe-rich and Si-containing multi-component alloy material provided in Example 2 of the present invention in a 3.5 wt.% NaCl solution.

11 is an XRD pattern of the Fe-rich and Si-containing multi-component alloy material provided in Example 3 of the present invention.

12 is a scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material provided in Example 3 of the present invention.

13 is a room temperature tensile curve of the Fe-rich and Si-containing multi-component alloy material provided in Example 3 of the present invention.

14 is a scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material provided in Example 3 of the present invention soaked in a 3.5 wt.% NaCl solution for 15 days.

FIG. 15 is the electrochemical polarization curve of the Fe-rich and Si-containing multi-component alloy material provided in Example 3 of the present invention in a 3.5 wt.% NaCl solution.

FIG. 16 is the electrochemical polarization curve of the equiatomic ratio CoCrFeMnNi multi-component alloy provided in Comparative Example 1 in a 3.5 wt. % NaCl solution.

Detailed ways

In order to make the above objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention will be described in detail below with reference to the embodiments of the specification.

Many specific details are set forth in the following description to facilitate a full understanding of the present invention, but the present invention can also be implemented in other ways different from those described herein, and those skilled in the art can do so without departing from the connotation of the present invention. Similar promotion, therefore, the present invention is not limited by the specific embodiments disclosed below.

Second, reference herein to "one embodiment" or "an embodiment" refers to a particular feature, structure, or characteristic that may be included in at least one implementation of the present invention. The appearances of "in one embodiment" in various places in this specification are not all referring to the same embodiment, nor are they separate or selectively mutually exclusive from other embodiments.

Example 1

(1) According to the chemical formula Fe ₃₄ Ni ₂₁ Cr ₂₀ Co ₂₀ Si ₅ (atomic percentage), the ingredients are prepared, and the raw materials use the blocks corresponding to each pure element (purity>99.9%), smelted under argon after cleaning, and repeatedly smelted 4 times. During smelting, the argon gas pressure is about 400Pa, the smelting temperature is about 1700°C, and the temperature is kept for 10 minutes.

(2) After obtaining the smelted alloy ingot, the alloy is subjected to multi-pass hot rolling treatment, the hot rolling temperature is 1000° C., the single rolling reduction is 15%, and the total rolling reduction is 60%.

(3) The hot-rolled alloy block is subjected to high temperature homogenization treatment in a vacuum environment (at a pressure of about 2Pa), the temperature is 1180°C, the homogenization treatment time is 3 hours, and then water quenched.

(4) The alloy block after high temperature homogenization is subjected to multiple passes of room temperature cold rolling, the single pass rolling reduction is 15%, and the total rolling reduction is 70%.

(5) annealing the cold-rolled alloy plate in a near-vacuum environment (at a pressure of about 2Pa), with an annealing temperature of 900° C. and an annealing time of 30 minutes to obtain an Fe-rich and Si-containing multi-component alloy material.

It can be seen from the XRD pattern of the Fe-rich Si-containing multi-component alloy material (Fig. 1) that the obtained Fe-rich Si-containing multi-component alloy material mainly exhibits a face-centered cubic (FCC) solid solution structure.

It can be seen from the scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material (Figure 2) that the Fe-rich and Si-containing multi-component alloy material obtained in this example is a completely recrystallized structure, and the recrystallized grains contain many annealing twins. The average grain size measured after excluding twins is about 10 μm.

It can be seen from the room temperature tensile curve of the Fe-rich and Si-containing multi-component alloy material (Fig. 3), the yield strength of the multi-component alloy obtained in this example is about 370MPa, the tensile strength is about 755MPa, and the elongation after fracture is about 82%. .

The Fe-rich and Si-containing multi-component alloy material provided in Example 1 was soaked in a 3.5wt.% NaCl solution for 15 days, and the scanning electron microscope image (Fig. 4) was observed, and there was no obvious corrosion phenomenon after soaking for 15 days.

The Fe-rich and Si-containing multi-component alloy material provided in Example 1 was tested for electrochemical performance through an electrochemical workstation equipped with a standard three-electrode system, and the reference electrode was a saturated calomel electrode. It can be seen from the electrochemical polarization curve in Figure 5 that the Fe-rich and Si-containing multi-component alloy obtained in this example exhibits obvious passivation in a 3.5wt.% NaCl solution, and the passivation current density is about 1.37×10 ^-6 A/cm ² , the corrosion potential is about -0.248V _SCE , and the breakdown potential of the passivation film is about 0.45V _SCE . Combining the results of Fig. 4 and Fig. 5, it can be seen that the Fe-rich and Si-containing multi-component alloy material provided in Example 1 has excellent corrosion resistance.

Example 2

(1) According to the chemical formula Fe _33.8 Ni ₁₉ Cr _19.2 Co ₂₀ Si ₈ (atomic percentage), the ingredients are prepared. The raw materials are the corresponding blocks (purity>99.9%) of each element. After cleaning, smelting is carried out under the condition of argon, and the smelting is repeated for 4 Second-rate. During smelting, the argon gas pressure is about 400Pa, the smelting temperature is about 1700°C, and the temperature is kept for 10 minutes.

(2) The smelted alloy ingot is subjected to multi-pass hot rolling treatment, the hot rolling temperature is 1100° C., the single pass rolling reduction is 10%, and the total rolling reduction is 50%.

(3) The hot-rolled alloy block is subjected to high temperature homogenization treatment in a near vacuum environment (pressure is about 2Pa), the temperature is 1180 ° C, the homogenization treatment time is 2 hours, and then water quenched.

(4) The alloy block after high temperature homogenization is subjected to multiple passes of room temperature cold rolling, the single pass rolling reduction is 20%, and the total rolling reduction is 70%.

(5) The cold-rolled alloy plate is annealed in a near-vacuum environment (the pressure is about 2Pa), the annealing temperature is 900°C, and the annealing time is 30 minutes to obtain an Fe-rich and Si-containing multi-component alloy material.

It can be seen from the XRD pattern of the Fe-rich and Si-containing multi-component alloy material (FIG. 6) that the Fe-rich Si-containing multi-component alloy material obtained in this example also mainly exhibits a face-centered cubic (FCC) solid solution structure.

It can be seen from the scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material (Fig. 7) that the solid solution structure multi-component alloy obtained in this example is also in a completely recrystallized state, and the recrystallized grains contain many annealing twins, eliminating twinning The average grain size measured after crystallisation is about 20 μm.

It can be seen from the room temperature tensile curve of the Fe-rich and Si-containing multi-component alloy material (Fig. 8), the yield strength of the multi-component alloy obtained in this example is about 350MPa, the tensile strength is about 800MPa, and the elongation after fracture is about 75%. .

The Fe-rich and Si-containing multi-component alloy material provided in Example 2 was immersed in a 3.5wt.% NaCl solution for 15 days, and the scanning electron microscope image (Fig. 9) was observed to show that there was no obvious corrosion phenomenon after 15 days of immersion.

The electrochemical performance test of the Fe-rich and Si-containing multi-component alloy material provided in Example 2 is the same as that of Example 1. It can be seen from the electrochemical polarization curve in FIG. 10 that the Fe-rich and Si-containing multi-component alloys obtained in this example The sub-alloys show obvious passivation in 3.5wt.%NaCl solution, the passivation current density is about 2.22×10 ^-6 A/cm ² , the corrosion potential is about -0.287V _SCE , and the breakdown potential of the passivation film is about is 0.944V _SCE . It can be seen from the results of FIG. 9 and FIG. 10 that the Fe-rich and Si-containing multi-component alloy material provided in Example 2 has excellent corrosion resistance.

Example 3

(1) Use pure element particles (Fe, Ni, Cr, Co, Si) with a purity of 99.9% as raw materials, and carry out ingredients according to the chemical formula Fe ₃₀ Ni ₂₀ Cr ₁₉ Co ₂₁ Si ₁₀ (atomic percentage). The smelting is carried out in a vacuum arc furnace, and the smelting is repeated 5 times. A small amount of argon is filled during smelting, the air pressure is kept at about 400Pa, the smelting temperature is about 1800 °C, and the temperature is kept for 20 minutes.

(2) The smelted alloy ingot is subjected to multi-pass hot rolling treatment, the hot rolling temperature is 1100° C., the single rolling reduction is 15%, and the total rolling reduction is 60%.

(3) The hot-rolled alloy block is subjected to high temperature homogenization treatment in a near-vacuum environment (gas pressure is about 2Pa), the temperature is 1200° C., the homogenization treatment time is 3 hours, and then water quenched.

(4) Multi-pass room temperature rolling is performed on the alloy block after high temperature homogenization, and the single pass rolling reduction is 10%, and the total rolling reduction is 70%.

(5) The cold-rolled alloy plate is annealed in a near-vacuum environment (at a pressure of about 2Pa), the annealing temperature is 950°C, and the annealing time is 5 minutes to obtain an Fe-rich and Si-containing multi-component alloy material.

It can be seen from the XRD pattern of the Fe-rich and Si-containing multi-component alloy material (FIG. 11) that the multi-component alloy obtained in this example also exhibits a face-centered cubic (FCC) solid solution structure.

From the scanning electron microscope image of the Fe-rich and Si-containing multi-component alloy material (Fig. 12), it can be seen that this example presents a completely recrystallized structure and contains many annealing twins. The average grain size measured after excluding the twins is about 15 μm. ;

It can be seen from the room temperature tensile curve of the Fe-rich and Si-containing multi-component alloy material (Fig. 13) that the yield strength of this embodiment is about 395 MPa, the tensile strength is about 900 MPa, and the elongation after fracture is about 83%.

The Fe-rich and Si-containing multi-component alloy material provided in Example 3 was soaked in a 3.5wt.% NaCl solution for 15 days, and the scanning electron microscope image (Fig. 14) was observed, and there was no obvious corrosion phenomenon after soaking for 15 days.

The electrochemical performance test of the Fe-rich and Si-containing multi-component alloy material provided in Example 3 is the same as that of Example 1. It can be seen from the electrochemical polarization curve in FIG. 15 that the Fe-rich and Si-containing multi-component alloys obtained in this example are The sub-alloy showed obvious passivation in 3.5wt.%NaCl solution, the self-corrosion current density was about 2.62×10 ^-6 A/cm ² , the corrosion potential was about -0.261V _SCE , and the breakdown potential of the passivation film was about 2.62×10 -6 A/cm 2 . is 0.97V _SCE . 14 and 15, it can be seen that Example 3 is excellent in corrosion resistance.

Comparative Example 1

According to the description in the literature (Sjsa B, Yzt A, Hrla B, et al. Enhanced strength and ductility of bulk CoCrFeMnNi high entropy alloy having fully recrystallized ultrafine-grained structure[J]. Materials & Design, 2017, 133: 122-127.), prepared Equal atomic ratio CoCrFeMnNi multi-component alloy material; Equal atomic ratio CoCrFeMnNi multi-component alloy has a yield strength of 310MPa at room temperature, a tensile strength of 725MPa, and an elongation of only 58%.

The electrochemical performance test of the equiatomic CoCrFeMnNi alloy material provided in Comparative Example 1 is the same as that of Example 1. It can be seen from the electrochemical polarization curve in Figure 16 that the equiatomic CoCrFeMnNi alloy is in 3.5wt.%NaCl solution. The corrosion potential is about -0.227V _SCE , the pitting corrosion potential is about 0.01V _SCE , and there is almost no passivation interval.

Comparing Example 3 and Comparative Example 1, it can be seen that the breakdown potential of the passivation film of the Fe-rich and Si-containing multi-component alloy material with corrosion resistance, high strength and toughness of the present invention is 0.9 V _SCE higher than that of the CoCrFeMnNi multi-component alloy, showing a more stable performance. passivation film.

Comparing Figure 5, Figure 6, Figure 15 and Figure 16: Corrosion potential and corrosion current density of Fe-rich and Si-containing multi-component alloy materials prepared in Examples 1, 2, and 3 in 3.5wt.%NaCl solution It is equivalent to the equiatomic ratio CoCrFeMnNi high-entropy alloy, but the breakdown potential of the passivation film in Examples 1, 2, and 3 is much higher than that of the equiatomic ratio CoCrFeMnNi high-entropy alloy, indicating that the Fe-rich and Si-rich prepared in Examples 1, 2, and 3 The multi-component alloy material has better resistance to chloride ion corrosion than the equiatomic ratio CoCrFeMnNi high-entropy alloy.

The Fe-rich and Si-containing multi-component alloy material provided by the present invention has the following characteristics in terms of component matching: through the introduction of Si, on the one hand, in a corrosive environment, Si and Cr are preferentially enriched on the surface of the material and promote the formation of The dense and stable passivation film improves the corrosion resistance of the alloy (see Figures 10, 11, and 12). On the other hand, by using the characteristic that the atomic radius of Si is quite different from that of Fe, Ni, Cr, and Co, a large lattice distortion is generated in the matrix of the face-centered cubic structure to hinder the movement of dislocations, which effectively improves the The solid solution strengthening effect in the alloy, and the addition of Si improves the work hardening ability of the alloy, and improves the strength and elongation of the alloy (see Figures 3 and 6). The above technical measures not only improve the strong plasticity of the alloy, but also ensure the corrosion resistance of the alloy.

In addition, the presence of higher content of Co and Ni can also help the alloy to form a face-centered cubic structure to a certain extent, so that the alloy can maintain a face-centered cubic structure under different processing states (such as casting, hot rolling, homogenization, etc.) feature. The face-centered cubic structure metal has more slip directions and slip systems, so it has better plasticity than the body-centered cubic structure and the close-packed hexagonal structure metal. It provides good tissue conditions for subsequent cold and thermoplastic deformation.

The higher Cr content in the Fe-rich and Si-containing multi-component alloy material of the present invention helps the alloy to form a dense and stable passivation film in a corrosive environment, thereby ensuring that the alloy has excellent corrosion resistance. At the same time, under the assistance of Si element, in a corrosive environment, Cr and Si are preferentially enriched on the surface of the material and effectively promote the formation of a dense and stable passivation film, further improving the corrosion resistance of the alloy. Higher contents of Fe, Co and Cr can also increase the solid solution strengthening effect in the alloy, which helps to increase the strength.

The multi-component alloy material of the present invention introduces a large amount of Si elements, and its comprehensive effect is briefly described as follows: 1) Si will preferentially reach the surface of the material in a corrosive environment, promote the formation of dense and stable SiO ₂ , and co-enrich with Cr ₂ O ₃ On the surface passivation film, the alloy has excellent corrosion resistance; 2) The atomic radius of Si is 0.117nm and the atomic radius of Fe, Ni, Cr, Co (0.126nm, 0.124nm, 0.128nm and 0.125nm respectively) The difference is large, which can cause large lattice distortion in the face-centered cubic structure matrix to hinder the movement of dislocations, effectively improve the solid solution strengthening effect in the alloy, and further improve the strength of the alloy; 3) Although the introduction of Si increases the The lattice distortion did not lead to the change of the face-centered cubic structure of the alloy. At the same time, the introduction of Si changed the dislocation movement form when the alloy was deformed, and the work hardening ability of the alloy was improved, so the plasticity was not deteriorated or even improved.

In addition, the hot rolling of the alloy ingot can effectively eliminate the defects (such as micropores, microcracks, etc.) generated in the alloy during smelting and casting, and improve the comprehensive properties of the alloy; the subsequent homogenization treatment can further promote the various groups in the alloy. The elements are uniformly distributed to form a face-centered cubic equiaxed grain structure with uniform composition, which further ensures that the alloy has good plasticity. Although the grain size of the alloy after homogenization treatment is larger, the subsequent cold rolling and recrystallization annealing treatment can effectively achieve grain refinement, and improve the strength of the alloy under the premise of ensuring good plasticity of the alloy.

The Fe-rich and Si-containing multi-component alloy material provided by the invention has the microstructure feature of the face-centered cubic solid solution structure as the matrix, which ensures good plasticity; High yield strength and good work hardening ability make tensile strength also high; at the same time, this kind of alloy has excellent resistance to chloride ion corrosion; its excellent comprehensive properties make it applicable to oceans with high chloride ion concentration in important structural components serving in the environment.

It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be Modifications or equivalent substitutions without departing from the spirit and scope of the technical solutions of the present invention should be included in the scope of the claims of the present invention.

Claims (10)

1. A high-strength, high-toughness and corrosion-resistant Fe-rich Si-containing multi-component alloy is characterized in that: according to atomic percentage, the alloy consists of 27-35% of Fe, 17-22% of Ni, 17-22% of Cr, 17-22% of Co and 3-15% of Si;

wherein the sum of the atomic percentage contents of Fe, Ni, Cr and Co is more than or equal to 85 percent; the sum of the atomic percentages of the components is 100 percent.

2. The method for preparing the high toughness corrosion resistant Fe-rich Si-containing multi-component alloy according to claim 1, wherein the method comprises the following steps: comprises the steps of (a) preparing a mixture of a plurality of raw materials,

preparing raw materials of each component according to atom percentage;

smelting under the protection of vacuum or inert gas to obtain an alloy casting blank;

and (3) carrying out hot rolling, homogenization, cold rolling and annealing treatment on the casting blank to obtain the Fe-rich Si-containing multi-component alloy.

3. The method for preparing the high toughness corrosion resistant Fe-rich Si-containing multi-component alloy according to claim 2, wherein: the raw materials of each component are prepared, the raw materials of each component adopt pure elements or blocks or particles of intermediate alloy, and the purity of the raw materials is more than or equal to 99.50 percent.

4. The method for preparing the high toughness corrosion resistant Fe-rich Si-containing multi-component alloy according to claim 2 or 3, wherein: smelting under the protection of vacuum or inert gas, and smelting under the vacuum condition, wherein the vacuum degree is 1-0.0001 Pa; smelting under the protection of inert gas, wherein the pressure of the inert gas is 100-500 Pa.

5. The method for preparing the high toughness corrosion resistant Fe-rich Si-containing multi-component alloy according to claim 4, wherein: and smelting at 1600-2300 ℃.

6. The method for preparing the high toughness corrosion resistant Fe-rich Si-containing multi-component alloy according to any one of claims 2, 3 and 5, wherein the method comprises the following steps: the casting blank is subjected to hot rolling, and multi-pass hot rolling is adopted, wherein the hot rolling temperature is 900-1200 ℃, the single rolling reduction is less than or equal to 30%, and the total rolling reduction is 50-80%.

7. The method for preparing the high toughness corrosion resistant Fe-rich Si-containing multi-component alloy according to claim 6, wherein: the homogenization temperature is 1100-1200 ℃, and the treatment time is 30-600 minutes.

8. The method for preparing the high toughness corrosion resistant Fe-rich Si-containing multi-component alloy according to any one of claims 2, 3, 5 and 7, wherein the method comprises the following steps: and in the cold rolling, multi-pass room-temperature cold rolling is adopted, the rolling reduction of a single pass is less than or equal to 20%, and the total rolling reduction is 50-90%.

9. The method for preparing the high toughness corrosion resistant Fe-rich Si-containing multi-component alloy according to any one of claims 2, 3, 5 and 7, wherein the method comprises the following steps: and annealing, wherein the annealing temperature is 800-1000 ℃, and the annealing time is 5-30 minutes.

10. Use of the high toughness, corrosion resistant Fe-rich, Si-containing multi-component alloy of claim 1 in corrosive environments.

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