Aluminum micro-alloying pitting corrosion resistant bulk zirconium-based amorphous alloy and preparation method thereof

Abstract

This invention discloses an aluminum-based microalloyed, pitting-resistant bulk zirconium-based amorphous alloy and its preparation method. The zirconium-based amorphous alloy is composed of Zr, Ti, Cu, Ni, Be, and Al, with the following atomic percentage content: (Zr...) a Ti b Cu c Ni d Be e ) 100‑x Al x , among them, a+b+c+d+e=100, a=41.2, b=13.8, c=12.5, d=10, e=22.5, 0

Description

Technical Field

[0001] This invention relates to a microalloyed aluminum-based zirconium-based amorphous alloy resistant to pitting corrosion and its preparation method, belonging to the field of metallic materials and their preparation technology. Background Technology

[0002] Zirconium-based amorphous alloys possess excellent properties such as high strength, high hardness, superior corrosion resistance, and good biocompatibility, making them a promising new type of metallic material with broad application prospects in marine engineering and ship equipment, hinges for foldable mobile phones in consumer electronics, and biomedicine. However, the ability to fabricate bulk zirconium-based amorphous alloys remains a major factor limiting their widespread application. Generally, the formation of bulk amorphous alloy systems requires excellent glass-forming capabilities, enabling the production of large amorphous alloys in millimeter or even centimeter sizes using water-cooled copper mold suction casting. Microalloying methods can effectively control the glass-forming ability of amorphous alloys, but currently, most microalloying elements are high-melting-point metals, rare earth metals, and noble metals. Systems with good glass-forming capabilities are still relatively few, and the fabrication cost and processes present certain challenges.

[0003] Chinese patent (CN101619425A) discloses the preparation of amorphous alloy rods with a diameter of 2 mm by introducing high-melting-point Nb into the traditional ZrCuNiAl system. This system has a relatively narrow compositional design window and is highly dependent on vacuum melting and cooling process conditions. It is difficult to stably prepare large-sized bulk amorphous alloys using water-cooled copper mold suction casting, thus limiting its application in engineering structural components and large-size functional parts. Chinese patent (CN104745973A) discloses the preparation of a multi-component ZrCuAlNiHfErY zirconium-based amorphous alloy with excellent glass-forming ability by micro-doping with rare earth Er. However, its complex composition and sensitivity to the amount of rare earth elements added limit its engineering applications. Chinese patent (CN101314838A) discloses the preparation of 2 mm diameter ZrCuNiAlAg amorphous alloy rods by introducing the noble metal Ag through micro-alloying. Chinese patent (CN102080196A) discloses the preparation of centimeter-scale bulk amorphous alloys by adding trace amounts of one or more elements such as Y, Sc, or La to the ZrCuAlNiAg system. However, the alloy composition contains both noble metals and rare earth elements, and has a large number of components. In summary, existing technologies generally suffer from strong dependence on high-melting-point metal elements, noble metal elements, rare earth elements, or complex alloying elements, high process sensitivity, limited bulk size, or difficulty in achieving a balance of comprehensive performance. Therefore, there is a need to provide a method for preparing bulk zirconium-based amorphous alloys by microalloying with low-melting-point, low-cost elements to meet the needs of practical engineering applications.

[0004] On the other hand, in harsh service environments such as marine engineering, chemical equipment, biomedical implants, and nuclear reactors, materials not only need to be stably prepared into bulk amorphous alloys, but also require excellent corrosion resistance, especially against Cl. - ,Br - I - Halogen ion-induced pitting corrosion exhibits excellent resistance. As a type of localized corrosion, pitting corrosion easily leads to localized thinning of components, stress concentration, and subsequently, crack initiation and propagation, resulting in sudden fracture failure and seriously threatening the safety and lifespan of equipment and facilities. Existing technologies for improving the pitting corrosion resistance of amorphous alloys mainly include surface treatment, external physical field modulation, and alloy composition optimization. Among these, compositional modulation through microalloying is considered an effective way to improve the pitting corrosion resistance of materials. Chinese patent (CN115961220A) discloses a method for improving the pitting corrosion resistance of Zr-based amorphous alloys by adding Ti and combining it with complex electrochemical cathode hydrogen charging treatment. However, this process is cumbersome, costly, and excessive alloying element addition may adversely affect the glass-forming ability of the system.

[0005] Aluminum (Al) is a low-melting-point, lightweight, and inexpensive metal. Its oxides are dense, stable, and possess strong healing properties, making them ideal components for improving the protective performance of passivation films. The purpose of this invention is to provide a microalloyed aluminum-based bulk zirconium-based amorphous alloy resistant to pitting corrosion and its preparation method. This zirconium-based amorphous alloy has a simple composition, low cost, and mature preparation process. It exhibits excellent pitting corrosion resistance in halide solutions, which is of great significance for promoting its application in marine engineering and ship equipment, hinges for foldable mobile phones in consumer electronics, and biomedical fields. Summary of the Invention

[0006] The purpose of this invention is to provide an aluminum-microalloyed, pitting-resistant bulk zirconium-based amorphous alloy and its preparation method. The preparation method is simple and low-cost. The prepared bulk zirconium-based amorphous alloy has good glass-forming ability and exhibits excellent pitting resistance in halogen element solutions without surface treatment.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A microalloyed aluminum-based bulk zirconium-based amorphous alloy resistant to pitting corrosion, wherein the constituent elements of the zirconium-based amorphous alloy are Zr, Ti, Cu, Ni, Be, and Al, and their atomic percentage contents are as follows: (Zr a Ti b Cu c Ni d Be e ) 100-x Al x, among them, a+b+c+d+e=100, a=41.2, b=13.8, c=12.5, d=10, e=22.5, 0 <x≤20。

[0009] Preferably, the chemical formula of the zirconium-based amorphous alloy, based on atomic percentage content, is any of the following:

[0010] (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5 Al 0.5 ;(Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Al2;(Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 96 Al4;(Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 94 Al6; (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 92 Al8; (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 90 Al 10 .

[0011] The preparation method of any of the above-mentioned aluminum element microalloyed pitting resistant bulk zirconium-based amorphous alloys involves weighing each raw material according to atomic percentage content, mixing and melting them to obtain an alloy ingot, and then preparing an amorphous alloy rod by copper mold water cooling method.

[0012] Preferably, the purity of Zr, Ti, Cu, Ni, Be and Al used in the metal raw materials is ≥99.5%.

[0013] Preferably, the melting is carried out in a vacuum arc melting furnace (vacuum degree ≤ 5 × 10⁻⁶). -3Under a high-purity argon protective atmosphere, at a temperature of 1200-1600℃, the mixture is repeatedly melted more than 5 times, with each melting process lasting 2-5 minutes.

[0014] Preferably, this invention uses a water-cooled copper mold suction casting method to prepare bulk zirconium-based amorphous alloys. After obtaining the alloy ingot, the ingot is removed and its surface is mechanically polished to remove residual impurity layers and oxide layers formed by residual oxygen. Subsequently, the treated alloy ingot is placed in a copper crucible, and the electric arc melting furnace is evacuated again (vacuum degree ≤ 5 × 10⁻⁶). - 3 Under an argon protective atmosphere, the alloy ingot is reheated using a DC non-consumable electrode at a temperature of 1200-1600℃ to bring it back to a completely molten state. When the alloy ingot in the copper crucible is observed to be in a stable liquid state, the high-temperature melt is rapidly drawn into the water-cooled copper mold cavity by generating a pressure difference at both ends of the copper mold suction casting system, so that the melt can be rapidly cooled and solidified, thereby obtaining a dense bulk zirconium-based amorphous alloy rod.

[0015] Applications of any of the above-mentioned aluminum-based microalloyed, pitting-resistant bulk zirconium-based amorphous alloys in marine engineering and ship equipment, hinges for foldable mobile phones in consumer electronics, and biomedical applications.

[0016] The beneficial effects of this invention are as follows:

[0017] (1) Excellent glass-forming ability: Through reasonable aluminum element micro-alloying design, zirconium-based amorphous alloys have excellent glass-forming ability, with a critical diameter d≥3 mm and a glass transition temperature T. g Not less than 610 K;

[0018] (2) Excellent pitting corrosion resistance: The addition of aluminum promotes the formation of composite passivation film on the surface of amorphous alloy, which significantly improves the pitting corrosion resistance in halogen element solutions (NaCl, NaBr, NaI), shifts the pitting potential positively, and significantly reduces the self-corrosion current density.

[0019] (3) Low cost and simple process: Amorphous alloy system does not contain expensive metal elements such as precious metals and rare earth metals, the composition is simple and the cost is low; the preparation process adopts standard vacuum melting and copper mold suction casting method, the process is mature and stable and easy to industrialize. Attached Figure Description

[0020] Figure 1 These are alloy rods of different sizes of the pitting-resistant bulk zirconium-based amorphous alloys prepared in Examples 1-4;

[0021] Figure 2 The images show the XRD patterns of the pitting-resistant bulk zirconium-based amorphous alloys prepared in Examples 1-4.

[0022] Figure 3 The following are DSC curves of the pitting-resistant bulk zirconium-based amorphous alloys prepared in Examples 1-4;

[0023] Figure 4 The pitting-resistant bulk zirconium-based amorphous alloy (Zr) prepared in Example 2 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Potential polarization curves of Al2 in halide solutions (NaCl, NaBr, NaI);

[0024] Figure 5 The pitting-resistant bulk zirconium-based amorphous alloy (Zr) prepared in Example 2 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Electron micrographs of the morphology of Al2 after etching in halogen element solutions (NaCl, NaBr, NaI). Detailed Implementation

[0025] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings. These examples are merely illustrative and do not limit the scope of protection of the present invention. The amorphous structure of the bulk zirconium-based amorphous alloy was determined using a Bruker D8A X-ray diffractometer (XRD) and differential scanning calorimetry (DSC). The corrosion current density and self-corrosion potential were obtained by electrochemical workstation testing. The surface morphology after corrosion was characterized by scanning electron microscopy (SEM).

[0026] Example 1

[0027] This embodiment illustrates the (Zr) provided by the present invention. 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5 Al 0.5 Pitting-resistant bulk zirconium-based amorphous alloys and their preparation methods.

[0028] Weigh the metal raw materials: according to the zirconium-based amorphous alloy composition (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5 Al 0.5Weigh out the metal raw materials Zr, Ti, Cu, Ni, Be, and Al. The total weight is 30g, of which Zr, Ti, Cu, Ni, Be, and Al are 18.6844g, 3.2847g, 3.9499g, 2.9184g, 1.0083g, and 0.15g, respectively.

[0029] Melting: Weigh the metal raw materials according to atomic percentage and place them into a vacuum arc melting furnace, then evacuate (vacuum degree ≤ 5 × 10⁻⁶). -3 The mixture is filled with high-purity argon as a protective gas and repeatedly melted at 1500℃ for 5 times, each time for 3 minutes, to obtain a uniformly melted master alloy ingot.

[0030] Water-cooled copper mold suction casting: The master alloy ingot is removed and its surface is mechanically polished to remove residual impurities and oxide layers formed by residual oxygen. The polished master alloy ingot is placed into the copper crucible of the electric arc melting furnace, and vacuum is applied again (vacuum degree ≤ 5 × 10⁻⁶). -3 Under the protection of high-purity argon, the master alloy ingot is reheated using a DC non-consumable electrode to a temperature of 1500℃, so that it reaches a completely molten state again. When the master alloy ingot in the copper crucible is observed to be in a stable liquid state, the high-temperature melt is rapidly drawn into the water-cooled copper mold by generating a pressure difference at both ends of the copper mold suction casting system, so as to obtain a bulk zirconium-based amorphous alloy rod with a diameter of 5mm and a length of 150mm.

[0031] Electrochemical testing: (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5 Al 0.5 Electrochemical tests were performed on the amorphous alloy in 3.5 wt.% NaCl, 3.5 wt.% NaBr, and 3.5 wt.% NaI etching solutions. The electrochemical tests were conducted using a standard three-electrode system on a KOST CS350M electrochemical workstation. A platinum sheet was used as the counter electrode, and a saturated calomel electrode (SCE) was used as the reference electrode. (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5 Al 0.5Amorphous alloy was used as the working electrode. The three-electrode system was assembled in the electrolytic cell, ensuring the effective area of ​​the sample was completely immersed in the corrosion solution. First, an 1800s open-circuit potential (OCP) test was performed, and the sample was allowed to stabilize. Then, Tafel polarization curves were tested. The onset and termination potentials of the polarization test were set to -1 V and 1 V relative to the open-circuit potential (OCP), respectively, with a scan rate of 1 mV / s. The values ​​of corrosion current density, corrosion potential, and pitting potential obtained from the polarization test are detailed in Table 1. (Zr) 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5 Al 0.5 Corrosion potential E of amorphous alloy in 3.5 wt.% NaCl solution corr It is -179 mV, corrosion current density i corr It is 4.37×10 -7 A / cm 2 The pitting potential is -14 mV; the corrosion potential E in 3.5 wt.% NaBr solution is... corr It is -343 mV, corrosion current density i corr It is 4.29 × 10 -7 A / cm 2 The pitting potential is -46 mV; the corrosion potential E in 3.5 wt.% NaI solution is... corr It is -375 mV, corrosion current density i corr It is 6.04×10 -8 A / cm 2 The pitting potential is 74 mV.

[0032] Example 2

[0033] This embodiment illustrates the (Zr) provided by the present invention. 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Al2 pitting-resistant bulk zirconium-based amorphous alloy and its preparation method.

[0034] Weigh the metal raw materials: according to the zirconium-based amorphous alloy composition (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98Al2, weigh out the metal raw materials Zr, Ti, Cu, Ni, Be and Al. The total weight is 30g, of which the metal blocks of Zr, Ti, Cu, Ni, Be and Al are 18.4028g, 3.2352g, 3.8904g, 2.8744g, 0.9931g and 0.6g respectively.

[0035] Melting: Weigh the metal raw materials according to atomic percentage and place them into a vacuum arc melting furnace, then evacuate (vacuum degree ≤ 5 × 10⁻⁶). -3 The mixture is filled with high-purity argon as a protective gas and repeatedly melted at 1500℃ for 5 times, each time for 3 minutes, to obtain a uniformly melted master alloy ingot.

[0036] Water-cooled copper mold suction casting: The master alloy ingot is removed and its surface is mechanically polished to remove residual impurities and oxide layers formed by residual oxygen. The polished master alloy ingot is placed into the copper crucible of the electric arc melting furnace, and vacuum is applied again (vacuum degree ≤ 5 × 10⁻⁶). -3 Under the protection of high-purity argon, the master alloy ingot is reheated using a DC non-consumable electrode to a temperature of 1500℃, so that it reaches a completely molten state again. When the master alloy ingot in the copper crucible is observed to be in a stable liquid state, the high-temperature melt is rapidly drawn into the water-cooled copper mold by generating a pressure difference at both ends of the copper mold suction casting system, so as to obtain a bulk zirconium-based amorphous alloy rod with a diameter of 5mm and a length of 150mm.

[0037] Electrochemical testing: (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Electrochemical tests were performed on Al2 amorphous alloys in 3.5 wt.% NaCl, 3.5 wt.% NaBr, and 3.5 wt.% NaI etching solutions. The electrochemical tests were conducted using a standard three-electrode system on a KOST CS350M electrochemical workstation. A platinum sheet was used as the counter electrode, and a saturated calomel electrode (SCE) was used as the reference electrode. (Zr...) 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5Al2 amorphous alloy was used as the working electrode. The three-electrode system was assembled in the electrolytic cell, ensuring the effective area of ​​the sample was completely immersed in the corrosion solution. First, an 1800s open-circuit potential (OCP) test was performed, and the sample was allowed to stabilize. Then, Tafel polarization curves were measured. The onset and termination potentials of the polarization test were set to -1 V and 1 V relative to the open-circuit potential (OCP), respectively, with a scan rate of 1 mV / s. The values ​​of corrosion current density, corrosion potential, and pitting potential obtained from the polarization test are detailed in Table 1. (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5 Corrosion potential E of Al2 amorphous alloy in 3.5 wt.% NaCl solution corr It is -164 mV, corrosion current density i corr It is 1.05×10 -7 A / cm 2 The pitting potential is -14 mV; the corrosion potential E in 3.5 wt.% NaBr solution is... corr It is -395 mV, corrosion current density i corr It is 3.78×10 -8 A / cm 2 The pitting potential is -28 mV; the corrosion potential E in 3.5 wt.% NaI solution is... corr It is -349 mV, corrosion current density i corr It is 6.84 × 10 -8 A / cm 2 The pitting potential is 58 mV.

[0038] Example 3

[0039] This embodiment illustrates the (Zr) provided by the present invention. 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 96 Al4 pitting-resistant bulk zirconium-based amorphous alloy and its preparation method.

[0040] Weigh the metal raw materials: according to the zirconium-based amorphous alloy composition (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 96Al4, weigh out the metal raw materials Zr, Ti, Cu, Ni, Be and Al. The total weight is 30g, of which the metal blocks of Zr, Ti, Cu, Ni, Be and Al are 18.0272g, 3.1692g, 3.8109g, 2.8158g, 0.9728g and 1.2g respectively.

[0041] Melting: Weigh the metal raw materials according to atomic percentage and place them into a vacuum arc melting furnace, then evacuate (vacuum degree ≤ 5 × 10⁻⁶). -3 The mixture is filled with high-purity argon as a protective gas and repeatedly melted at 1500℃ for 5 times, each time for 3 minutes, to obtain a uniformly melted master alloy ingot.

[0042] Water-cooled copper mold suction casting: The master alloy ingot is removed and its surface is mechanically polished to remove residual impurities and oxide layers formed by residual oxygen. The polished master alloy ingot is placed into the copper crucible of the electric arc melting furnace, and vacuum is applied again (vacuum degree ≤ 5 × 10⁻⁶). -3 Under the protection of high-purity argon, the master alloy ingot is reheated using a DC non-consumable electrode to a temperature of 1500℃, so that it reaches a completely molten state again. When the master alloy ingot in the copper crucible is observed to be in a stable liquid state, the high-temperature melt is rapidly drawn into the water-cooled copper mold by generating a pressure difference at both ends of the copper mold suction casting system, so as to obtain a bulk zirconium-based amorphous alloy rod with a diameter of 3mm and a length of 150mm.

[0043] Electrochemical testing: (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Electrochemical tests were performed on Al4 amorphous alloys in 3.5 wt.% NaCl, 3.5 wt.% NaBr, and 3.5 wt.% NaI etching solutions. The electrochemical tests were conducted using a standard three-electrode system on a KOST CS350M electrochemical workstation. A platinum sheet was used as the counter electrode, and a saturated calomel electrode (SCE) was used as the reference electrode. (Zr...) 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5Al4 amorphous alloy was used as the working electrode. The three-electrode system was assembled in the electrolytic cell, ensuring the effective area of ​​the sample was completely immersed in the corrosion solution. First, an 1800s open-circuit potential (OCP) test was performed, and the sample was allowed to stabilize. Then, Tafel polarization curves were measured. The onset and termination potentials of the polarization test were set to -1 V and 1 V relative to the open-circuit potential (OCP), respectively, at a scan rate of 1 mV / s. The values ​​of corrosion current density, corrosion potential, and pitting potential obtained from the polarization test are detailed in Table 1. (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5 Corrosion potential E of Al4 amorphous alloy in 3.5 wt.% NaCl solution corr It is -193 mV, corrosion current density i corr It is 1.45×10 -7 A / cm 2 The pitting potential is -22 mV; the corrosion potential E in 3.5 wt.% NaBr solution is... corr It is -381 mV, corrosion current density i corr It is 7.58×10 -8 A / cm 2 The pitting potential is -54 mV; the corrosion potential E in 3.5 wt.% NaI solution is... corr It is -355 mV, corrosion current density i corr It is 1.28×10 -7 A / cm 2 The pitting potential is 53 mV.

[0044] Example 4

[0045] This embodiment illustrates the (Zr) provided by the present invention. 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 94 Al6 pitting-resistant bulk zirconium-based amorphous alloy and its preparation method

[0046] Weigh the metal raw materials: according to the zirconium-based amorphous alloy composition (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 94Al6 is prepared by weighing out the following metal raw materials: Zr, Ti, Cu, Ni, Be, and Al. The total weight is 30g, of which the metal blocks of Zr, Ti, Cu, Ni, Be, and Al are 17.6516g, 3.1032g, 3.7316g, 2.7571g, 0.9526g, and 1.8g, respectively.

[0047] Melting: Weigh the metal raw materials according to atomic percentage and place them into a vacuum arc melting furnace, then evacuate (vacuum degree ≤ 5 × 10⁻⁶). -3 The mixture is filled with high-purity argon as a protective gas and repeatedly melted at 1500℃ for 5 times, each time for 3 minutes, to obtain a uniformly melted master alloy ingot.

[0048] Water-cooled copper mold suction casting: The master alloy ingot is removed and its surface is mechanically polished to remove residual impurities and oxide layers formed by residual oxygen. The polished master alloy ingot is placed into the copper crucible of the electric arc melting furnace, and vacuum is applied again (vacuum degree ≤ 5 × 10⁻⁶). -3 Under the protection of high-purity argon, the master alloy ingot is reheated using a DC non-consumable electrode to a temperature of 1500℃, so that it reaches a completely molten state again. When the master alloy ingot in the copper crucible is observed to be in a stable liquid state, the high-temperature melt is rapidly drawn into the water-cooled copper mold by generating a pressure difference at both ends of the copper mold suction casting system, so as to obtain a bulk zirconium-based amorphous alloy rod with a diameter of 3mm and a length of 150mm.

[0049] Electrochemical testing: (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Electrochemical tests were performed on Al6 amorphous alloys in 3.5 wt.% NaCl, 3.5 wt.% NaBr, and 3.5 wt.% NaI etching solutions. The electrochemical tests were conducted using a standard three-electrode system on a KOST CS350M electrochemical workstation. A platinum sheet was used as the counter electrode, and a saturated calomel electrode (SCE) was used as the reference electrode. (Zr...) 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 99.5Al6 amorphous alloy was used as the working electrode. The three-electrode system was assembled in the electrolytic cell, ensuring the effective area of ​​the sample was completely immersed in the corrosion solution. First, an 1800s open-circuit potential (OCP) test was performed, and the sample was allowed to stabilize. Then, Tafel polarization curves were measured. The onset and termination potentials of the polarization test were set to -1 V and 1 V relative to the open-circuit potential (OCP), respectively, with a scan rate of 1 mV / s. The values ​​of corrosion current density, corrosion potential, and pitting potential obtained from the polarization test are detailed in Table 1. (Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 94 Corrosion potential E of Al6 amorphous alloy in 3.5 wt.% NaCl solution corr It is -240 mV, corrosion current density i corr It is 2.31×10 -7 A / cm 2 The pitting potential is -77 mV; the corrosion potential E in 3.5 wt.% NaBr solution is... corr It is -395 mV, corrosion current density i corr It is 6.46 × 10 -7 A / cm 2 The pitting potential is -40 mV; the corrosion potential E in 3.5 wt.% NaI solution is... corr It is -372 mV, corrosion current density i corr It is 1.55×10 -7 A / cm 2 The pitting potential is 119 mV.

[0050] Figure 1 These are the aluminum-microalloyed bulk zirconium-based amorphous alloy rods prepared in Examples 1-4. (The last part, "Zr," appears to be incomplete and unrelated to the preceding text. It likely refers to a specific type of aluminum alloy.) 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 When 0.5 at.% Al and 2 at.% Al are added, the critical size of the zirconium-based amorphous alloy is 5 mm, and when 4 at.% Al and 6 at.% Al are added, the critical size of the zirconium-based amorphous alloy is 3 mm.

[0051] Figure 2 The images show the XRD patterns of the pitting-resistant bulk zirconium-based amorphous alloys prepared in Examples 1-4. The alloys all exhibit broadened diffuse diffraction peaks (bun peaks) without sharp crystallization peaks, indicating that the zirconium-based amorphous alloys prepared in Examples 1-4 are all amorphous alloys.

[0052] Figure 3These are DSC curves of the pitting-resistant bulk zirconium-based amorphous alloys prepared in Examples 1-4, with their glass transition temperatures being T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T2 ... g = 611 K, T g = 674 K, T g = 693K and T g = 712 K; crystallization temperatures are respectively T x = 725 K, T x = 725 K, T x = 737 K and T x = 750 K; the widths of the supercooled liquid phase region are ΔT = 64 K, ΔT = 55 K, ΔT = 42 K and ΔT = 38 K, respectively. The results show that with the increase of Al content, the glass transition temperature and crystallization temperature of zirconium-based amorphous alloys gradually increase, and the width of the supercooled liquid phase region gradually decreases.

[0053] Figure 4 This is Example 2 (Zr) 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Potentiodynamic polarization curves of Al2 amorphous alloys in halide solutions (3.5 wt.% NaCl, 3.5 wt.% NaBr and 3.5 wt.% NaI) show that the corrosion current density in 3.5 wt.% NaBr and 3.5 wt.% NaI is significantly lower than that in 3.5 wt.% NaCl.

[0054] Figure 5 This is Example 2 (Zr) 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 Electron microscopy images of the morphology of Al2 amorphous alloy after etching in halide solutions (3.5 wt.% NaCl, 3.5 wt.% NaBr, and 3.5 wt.% NaI). It can be seen that (Zr... 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 ) 98 The surface morphology of the Al2 amorphous alloy remains intact, with only a small number of micron-sized and discretely distributed pits appearing in local areas. No obvious corrosion expansion or interconnected corrosion areas have formed, indicating that the passivation film on the surface of this metal material has good stability and self-healing ability, and the material as a whole still exhibits excellent pitting corrosion resistance.

[0055] Table 1 compares the electrochemical corrosion performance of zirconium-based amorphous alloys and commonly used engineering metals in halide solutions in Examples 1-4. The corrosion current density and corrosion potential of a material characterize its corrosion resistance; a lower corrosion current density and higher corrosion potential indicate better corrosion resistance. The pitting potential of a material characterizes its resistance to pitting corrosion; a higher pitting potential indicates better corrosion resistance.

[0056] The corrosion current densities of the zirconium-based amorphous alloys in 3.5 wt.% NaCl solution in Examples 1-4 are basically equivalent to those of 304 stainless steel, and are much lower than those of Al-Si alloy and 6082 aluminum alloy. Their corrosion potentials are higher than those of Al-Si alloy, 304 stainless steel, and 6082 aluminum alloy, and their pitting potentials are also higher than those of Al-Si alloy, 304 stainless steel, and 6082 aluminum alloy. This indicates that the zirconium-based amorphous alloys in Examples 1-4 exhibit better corrosion resistance than Al-Si alloy, 304 stainless steel, and 6082 aluminum alloy in 3.5 wt.% NaCl solution. Specifically, taking Example 4 as an example, its corrosion current density is 0.0286 times, 0.2884 times, and 0.2221 times that of Al-Si alloy, 304 stainless steel, and 6082 aluminum alloy, respectively; its corrosion potential is 482mV, 91mV, and 548mV higher than that of Al-Si alloy, 304 stainless steel, and 6082 aluminum alloy, respectively; and its pitting potential is 603mV, 24mV, and 581mV higher than that of Al-Si alloy, 304 stainless steel, and 6082 aluminum alloy, respectively.

[0057] The corrosion current densities of the zirconium-based amorphous alloys in Examples 1–4 in 3.5 wt.% NaBr solution were 1–3 orders of magnitude lower than those of the Ti6Al4V and Al-Si alloys; their corrosion potentials were all higher than those of the Ti6Al4V and Al-Si alloys, and their pitting potentials were also higher than those of the Ti6Al4V and Al-Si alloys, indicating that the zirconium-based amorphous alloys in Examples 1–4 exhibited superior corrosion resistance in 3.5 wt.% NaBr solution compared to the Ti6Al4V and Al-Si alloys. Specifically, taking Example 4 as an example, its corrosion current density was approximately 0.0240 times and 0.1499 times that of the Ti6Al4V and Al-Si alloys, respectively; its corrosion potential was 294 mV and 154 mV higher than that of the Ti6Al4V and Al-Si alloys, respectively; and its pitting potential was 75 mV and 540 mV higher than that of the Ti6Al4V and Al-Si alloys, respectively.

[0058] The corrosion current densities of the zirconium-based amorphous alloys in 3.5 wt.% NaI solution in Examples 1-4 are 1-2 orders of magnitude lower than those of Al-Si alloys and 201Cu stainless steel. Their corrosion potentials and pitting potentials are also higher than those of Al-Si alloys and 201Cu stainless steel, indicating that the zirconium-based amorphous alloys in Examples 1-4 exhibit superior corrosion resistance in 3.5 wt.% NaI solution compared to Al-Si alloys and 201Cu stainless steel. Specifically, taking Example 4 as an example, its corrosion current density is approximately 0.0282 times and 0.0662 times that of Al-Si alloys and 201Cu stainless steel, respectively; its corrosion potential is higher than 377 mV and 504 mV of Al-Si alloys and 201Cu stainless steel, respectively; and its pitting potential is higher than 499 mV and 369 mV of Al-Si alloys and 201Cu stainless steel, respectively.

[0059] Table 1

[0060]

[0061] In summary, the zirconium-based amorphous alloy provided by this invention exhibits excellent corrosion resistance in halide solutions, especially its pitting corrosion resistance in halide solutions, which is superior to that of traditional alloy materials.

[0062] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A microalloyed aluminum-based zirconium-based amorphous alloy resistant to pitting corrosion, characterized in that, The zirconium-based amorphous alloy is composed of Zr, Ti, Cu, Ni, Be, and Al, with the following atomic percentage content: (Zr a Ti b Cu c Ni d Be e ) 100-x Al x , among them, a+b+c+d+e =100, a=41.2, b=13.8, c=12.5, d=10, e=22.5, 0 <x≤20。 2. The aluminum element microalloyed corrosion resistant bulk zirconium-based amorphous alloy of claim 1, wherein, Based on atomic percentage content, the chemical formula of zirconium-based amorphous alloys is any of the following: (Zr 41.2 A 13.8 The 12.5 Ni 10 Heart 22.5 ) 99.5 Al 0.5 ;(Zr 41.2 A 13.8 The 12.5 Ni 10 Heart 22.5 ) 98 Al2;(Zr 41.2 A 13.8 The 12.5 Ni 10 Heart 22.5 ) 96 Al4;(Zr 41.2 A 13.8 The 12.5 Ni 10 Heart 22.5 ) 94 Al6;(Zr 41.2 A 13.8 The 12.5 Ni 10 Heart 22.5 ) 92 Al8;(Zr 41.2 A 13.8 The 12.5 Ni 10 Heart 22.5 ) 90 Al 10 。 3. The method for preparing the aluminum-based microalloyed pitting-resistant bulk zirconium-based amorphous alloy according to any one of claims 1-2, characterized in that, The process involves weighing each raw material according to its atomic percentage content, mixing and melting them to obtain an alloy ingot, and then preparing amorphous alloy rods using a water-cooled copper mold suction casting method.

4. The method for preparing aluminum-element microalloyed pitting-resistant bulk zirconium-based amorphous alloy according to claim 3, characterized in that, The purity of Zr, Ti, Cu, Ni, Be and Al used in the metal raw materials is ≥99.5%.

5. The method for preparing aluminum-element microalloyed pitting-resistant bulk zirconium-based amorphous alloy according to claim 3, characterized in that, The smelting conditions are: vacuum degree ≤ 5 × 10⁻⁶ -3 Pa, inert atmosphere, 1200-1600℃, 2-5 min.

6. The method for preparing aluminum-element microalloyed pitting-resistant bulk zirconium-based amorphous alloy according to claim 5, characterized in that, The number of smelting operations is ≥5.

7. The method for preparing aluminum-element microalloyed pitting-resistant bulk zirconium-based amorphous alloy according to claim 5 or 6, characterized in that, An inert atmosphere is an argon atmosphere.

8. The application of the aluminum element microalloyed pitting-resistant bulk zirconium-based amorphous alloy as described in any one of claims 1-2 in marine engineering and ship equipment, hinges for consumer electronics foldable screen mobile phones, and biomedical applications.

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