A soluble magnesium alloy material and a method for producing the same

Abstract

The application discloses a soluble magnesium alloy material and a preparation method thereof, and belongs to the technical field of metal material processing. The soluble magnesium alloy material is Mg a Al b Zn c Mn d La e Nd f Ni g Alloy, wherein a+b+c+d+e+f+g=100%, 7.5wt.%.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metal material processing, and particularly relates to a soluble magnesium alloy material and a preparation method thereof. BACKGROUND

[0002] With the continuous growth of global energy demand, oil and gas exploitation technology is also advancing. In the process of oil and gas exploitation, traditional downhole tools often need to be recovered or treated after the operation is completed, which not only increases the operation cost, but also may cause environmental pollution.

[0003] To solve this problem, soluble magnesium alloy has become the ideal material for fracturing balls, bridge plugs and other soluble downhole tools. This material has the characteristics of dissolving under certain conditions, forming effective plugging and separation in the downhole, and achieving the purpose of separate layer fracturing. After the operation is completed, the soluble magnesium alloy can dissolve itself, avoiding subsequent flowback, drilling and milling processes, improving construction efficiency, saving construction cost and reducing energy consumption.

[0004] However, there are still deficiencies in the research on soluble magnesium alloy materials, and there are fewer types of soluble magnesium alloy materials to choose from. Moreover, the existing soluble magnesium alloy has high cost and complex process flow, which is difficult to meet the large-scale industrial application of soluble magnesium alloy materials. SUMMARY

[0005] In view of the above technical problems, the application provides a soluble magnesium alloy material and a preparation method thereof.

[0006] To achieve the above purpose, the application provides the following technical scheme:

[0007] One of the purposes of the application is to provide a soluble magnesium alloy material, which is Mg a Al b Zn c Mn d La e Nd f Ni g alloy, wherein, according to a+b+c+d+e+f+g=100%, 7.5wt.%<b<10.0wt.%, 0.2wt.%<c<0.8wt.%, 0.15wt.%<d<0.5wt.%, 0wt.%<e<1.15wt.%, 0.35wt.%<f<0.65wt.%, 0.05wt.%<g<0.3wt.%, and the balance is a.

[0008] The application can meet the strict requirements of the mechanical properties of the temporary plugging material in the petroleum industry by precisely controlling the content of alloying elements, and can quickly dissolve after the oil and gas exploitation operation is completed, without additional cleaning steps, simplifying the operation process and improving the construction efficiency. The application is based on ZM5 magnesium alloy smelting, the number of Mg2Ni phase in the microstructure of the soluble magnesium alloy is controlled by adjusting the amount of Ni added, the scale of micro galvanic corrosion is affected, and then the dissolution rate of the soluble magnesium alloy is controlled, and the mechanical properties of the alloy are controlled by adjusting the content of La and Nd.

[0009] The second object of the application is to provide a preparation method of a soluble magnesium alloy material, comprising the following steps:

[0010] 1) Weigh ZM5 ingot, magnesium lanthanum intermediate alloy, magnesium neodymium intermediate alloy, magnesium nickel intermediate alloy and refining agent by mass, and preheat treatment;

[0011] 2) Under the protection of atmosphere, the ZM5 ingot is smelted as a smelting matrix, and after the surface is scraped, the magnesium lanthanum intermediate alloy, the magnesium neodymium intermediate alloy and the magnesium nickel intermediate alloy are added to the ZM5 melt for alloying and heat preservation to obtain a molten liquid; then the refining agent is added to the molten liquid for refining, and after standing and cooling, the surface is scraped, and the soluble magnesium alloy cast rod is cast under the inert atmosphere;

[0012] 3) The soluble magnesium alloy cast rod is subjected to homogenization treatment and hot extrusion processing to obtain a soluble magnesium alloy material.

[0013] Further, the atmosphere in step 2) is a mixed gas of CO2 and SF6, and the volume ratio of the two is 99:1.

[0014] Using a mixed gas as the protective gas can effectively prevent the oxidation of magnesium and magnesium alloy during smelting, reduce the generation of impurities such as magnesium oxide, and improve the purity and performance of the alloy. And SF6 gas has good insulation and chemical stability, which can provide a safe and reliable protection environment during smelting, reducing the operation risk.

[0015] Further, the temperature of the smelting in step 2) is 650-730℃, and the heat preservation time is 10-60min.

[0016] The smelting temperature can ensure that the alloying elements are fully melted and uniformly distributed, forming a good alloy structure, improving the mechanical properties of the material and the controllability of the dissolution rate. At the same time, unnecessary energy waste is avoided, and the production cost is reduced.

[0017] Further, the refining process of step 2) specifically comprises: passing argon into the molten liquid, stirring for 5-10 min at a temperature of 730-740℃, and standing for 30-60 min after the stirring is completed; the amount of the refining agent is 2-10% of the total mass of the molten liquid.

[0018] The refining conditions can effectively remove the gas and impurities in the molten liquid, improve the purity of the alloy, reduce defects such as pores and inclusions, and thus improve the mechanical properties and corrosion resistance of the material.

[0019] Controlling the amount of refining agent can ensure the refining effect and avoid the problems of cost increase and potential pollution caused by excessive use of refining agent.

[0020] Further, the temperature of the casting of step 2) is 680-700℃.

[0021] The temperature can ensure that the molten liquid has good fluidity, avoid internal defects (such as shrinkage holes, porosity, etc.) of the cast rod caused by excessively high or low temperature, and improve the quality and subsequent processing performance of the cast rod. And the appropriate casting temperature range helps to shorten the production cycle and improve the production efficiency.

[0022] Further, the homogenization treatment conditions of step 3) are: temperature 415±1℃, time 16h, and air cooling to room temperature.

[0023] The homogenization treatment conditions can effectively eliminate the composition segregation and internal stress in the ingot, make the alloy structure more uniform, and be beneficial to improve the mechanical properties and processing performance of the material. And it has better dimensional stability and performance consistency in the subsequent processing and use.

[0024] Further, the hot extrusion conditions of step 3) are: temperature 360-400℃, extrusion ratio 5-20, and extrusion speed 0.5-5mm / s.

[0025] The hot extrusion conditions can make the soluble magnesium alloy obtain good plastic deformation during hot extrusion, further refine the grains, and improve the strength and toughness of the material. And it provides more flexibility for actual production, which can be optimized and adjusted according to different product requirements and equipment conditions.

[0026] Further, the hot extrusion process further comprises aging treatment.

[0027] Further, the aging treatment conditions are: temperature 165±1℃, time 16h, and air cooling to room temperature.

[0028] The aging treatment condition can cause the second phase particles in the alloy to precipitate, further strengthen the matrix, improve the strength and hardness of the material, and maintain certain plasticity. And it helps to stabilize the size of the material and reduce deformation or cracking caused by phase change and other factors during subsequent use.

[0029] A third object of the present application is to provide an application of the soluble magnesium alloy material in the field of temporary plugging materials.

[0030] The performance characteristics of the soluble magnesium alloy material fully meet the requirements of temporary plugging materials in the oil industry, and can achieve efficient plugging and separation during oil and gas production, improving the effect of separate layer fracturing. After use, it can be naturally dissolved without the need for additional cleaning steps, avoiding environmental pollution problems caused by the recovery or processing of traditional downhole tools, and meeting the development trend of green energy exploration. It reduces subsequent flowback, drilling and milling processes, reduces construction cost and energy consumption, and improves the overall economic benefit of oil and gas production.

[0031] Compared with the prior art, the present application has the following advantages and technical effects:

[0032] (1) The present application excludes the use of elements such as Fe (iron), Cr (chromium) and Ti (titanium). Although these elements can improve the dissolution rate of magnesium alloy in aqueous solution containing chlorine, their solubility in magnesium and magnesium alloy melt at temperatures above 650℃ is very low, not more than 0.1%. This leads to the precipitation of these elements at the bottom of the melt during alloy smelting and standing, resulting in uneven distribution of ingot composition and leading to a decrease in the mechanical properties of the material. By removing these elements, the present application not only simplifies the preparation process of the material, but also reduces the production cost.

[0033] (2) The tensile strength of the soluble magnesium alloy provided by the present application can reach 301.79 MPa, the yield strength can reach 197.3 MPa, the elongation can reach 10.8%, and the dissolution rate can reach 136 mg / (cm 2 ·h). These characteristics make it suitable for use as a temporary plugging material in the oil industry. After use, the material can be naturally dissolved without the need for additional cleaning steps, thereby improving work efficiency and simplifying the operation process.

[0034] (3) The soluble magnesium alloy of the present application has low cost, simple preparation method, short process flow, is suitable for large-scale production, and has good application prospect. DETAILED DESCRIPTION

[0035] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this application. The illustrative embodiments of the present application and their description serve to explain the present application. They do not, however, limit the present application unduly.

[0036] Figure 1 A flow chart of the method for preparing the soluble magnesium alloy material according to an embodiment of the present application is shown in FIG. 1. DETAILED DESCRIPTION

[0037] Various exemplary embodiments of the present application will now be described in detail, which should be considered in a descriptive sense only and not for purposes of limitation to the present application. Rather, it is understood that certain aspects, particular features and embodiments of the application are described for illustrative purposes only and are not exhaustive of all aspects, particular features, and embodiments of the application.

[0038] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. In addition, where particular ranges of values are given, it is to be understood that each intervening value, to the upper or lower limit of the ranges is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed. The upper and lower limits of these smaller ranges can independently be included or excluded in the range, and are also encompassed by the application, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of the limits are also included.

[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application, the preferred methods and materials are described. All patents, patent applications, publications, and descriptions mentioned herein are incorporated by reference for the disclosure and

[0040] Many modifications and variations of this application can be made without departing from its spirit or scope, which will be apparent to those skilled in the art. Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. The specification and examples given are exemplary only. It is to be understood that the application is not limited in scope by the specific embodiments described herein. Rather, the intent is to embrace all changes and modifications that are within the spirit and scope of the application.

[0041] As used herein, the terms "comprises", "comprising", "includes", "including", "has", "having", "contains", "containing", or variations thereof, are intended to be open-ended terms that mean inclusion, but not limited to, the listed materials and methods.

[0042] An embodiment of the present application provides a soluble magnesium alloy material, the soluble magnesium alloy material being Mg a Al b Zn c Mn d La e Nd f Ni g Alloy, the letters a, b, c, d, e, f and g represent the mass percentage of the corresponding element component respectively: wherein 7.5wt.% < b < 10.0wt.%, b can be selected as 8wt.%;

[0043] 0.2wt.% < c < 0.8wt.%, c optionally 0.5wt%;

[0044] 0.15wt.% < d < 0.5wt.%, d optionally 0.25wt%;

[0045] 0wt.% < e < 1.15wt.%, e optionally 1wt%;

[0046] 0.35wt.% < f < 0.65wt.%, f optionally 0.45wt%;

[0047] 0.05wt.% < g < 0.3wt.%, g optionally 0.22wt%;

[0048] the balance being a;

[0049] a+b+c+d+e+f+g = 100%.

[0050] The soluble magnesium alloy material can be prepared by preheating, melting, casting, homogenization treatment, extrusion and aging treatment. The preparation process is simple and has good application prospect. In order to reduce the feeding steps and simplify the melting process, the ZM5 ingot is used instead of pure magnesium ingot as the melting matrix. The specific technical scheme is as follows:

[0051] A preparation method of a soluble magnesium alloy material, comprising the following steps:

[0052] 1) The ZM5 ingot, magnesium lanthanum intermediate alloy, magnesium neodymium intermediate alloy, magnesium nickel intermediate alloy and refining agent are weighed according to mass, preheated and treated to remove the moisture in the raw materials;

[0053] 2) The ZM5 ingot is melted under atmosphere protection, after surface slagging, the magnesium lanthanum intermediate alloy, magnesium neodymium intermediate alloy and magnesium nickel intermediate alloy are added into the ZM5 melt for alloying and heat preservation to obtain a molten liquid; then the refining agent is added into the molten liquid for refining, after the refining is completed, the molten liquid is statically cooled to a predetermined casting temperature, then the surface is slagged, and then the soluble magnesium alloy rod is cast under inert atmosphere;

[0054] 3) The soluble magnesium alloy rod is subjected to homogenization treatment;

[0055] 4) The soluble magnesium alloy ingot obtained in step 3) is processed into a rod material by hot extrusion;

[0056] 5) The rod material obtained in step 4) is subjected to aging treatment or not (that is, the aging treatment can be performed or not), to obtain a soluble magnesium alloy material.

[0057] In some optional embodiments, the magnesium lanthanum intermediate alloy in step 1) is MgLa 30The mass percentage of La is 30%, and the same below), and the magnesium neodymium intermediate alloy is MgNd 30 The magnesium nickel intermediate alloy is MgNi 30 In order to reduce the feeding steps and simplify the smelting process, the ZM5 ingot containing Mg, Al, Zn and Mn elements is used as the smelting matrix instead of the pure magnesium ingot.

[0058] In some optional embodiments, the atmosphere in step 2) is a mixed gas of CO2 and SF6, and the volume ratio of the two is 99:1.

[0059] In some optional embodiments, the smelting temperature in step 2) is 650-730℃, and the holding time is 10-60min. As a typical but non-limiting example, in the following embodiments of the present application, the smelting temperature can be selected as 730℃, and the holding time can be selected as 20min.

[0060] In some optional embodiments, the refining process in step 2) specifically includes: passing argon into the molten liquid, stirring for 5-10min at a temperature of 730-740℃, and standing for 30-60min after the stirring is completed; and the amount of the refining agent is 2-10% of the total mass of the molten liquid. As a typical but non-limiting example, in the following embodiments of the present application, the refining refers to stirring for 6min at a temperature of 735℃, standing for 30min after the stirring is completed, and the amount of the refining agent is 7% of the total mass of the molten liquid.

[0061] In some optional embodiments, the casting temperature in step 2) is 680-700℃. As a typical but non-limiting example, in the following embodiments of the present application, the casting temperature can be selected as 685℃.

[0062] In some optional embodiments, the homogenization treatment in step 3) is at a condition of 415±1℃×16h, and air cooling to room temperature.

[0063] In some optional embodiments, the hot extrusion in step 4) is at a condition of a temperature of 360-400℃, an extrusion ratio of 5-20, and an extrusion speed of 0.5-5mm / s. As a typical but non-limiting example, in the following embodiments of the present application, the hot extrusion temperature can be selected as 375℃, 380℃ or 390℃, the extrusion ratio can be selected as 14, and the extrusion speed can be selected as 1.4mm / s, 1.5mm / s or 2mm / s.

[0064] In some optional embodiments, the aging treatment in step 5) is at a condition of 165±1℃×16h, and air cooling to room temperature.

[0065] In the present application, “room temperature” refers to 20-30℃ unless otherwise specified.

[0066] The raw materials used in the present application are all purchased from the market.

[0067] The technical solutions of the present application are further illustrated by the following examples.

[0068] Figure 1 The flowchart of the preparation method of the soluble magnesium alloy material of the present application is shown in the following embodiment.

[0069] The ZM5 ingot used in the following embodiments of the present application is purchased from Shanxi Ruige Metal New Material Co., Ltd., wherein the main element content is: Mg: balance; Al: 7.5-9.0%; Zn: 0.2-0.8%; Mn: 0.15-0.5%.

[0070] Example 1

[0071] A soluble magnesium alloy material (extruded state + aged state)

[0072] The alloy is Mg-Al-Zn-Mn-La-Nd-Ni alloy, which is composed of the following elements with mass percentage: Al-8.15%, Zn-0.5%, Mn-0.25%, La-1%, Nd-0.45%, Ni-0.28%, and Mg balance, i.e. Mg 89.37 Al 8.15 Zn 0.5 Mn 0.25 La1Nd 0.45 Ni 0.28 Alloy.

[0073] The preparation process includes the following steps:

[0074] 1) According to the above element content ratio, weigh the ZM5 ingot, magnesium lanthanum intermediate alloy MgLa 30 , magnesium neodymium intermediate alloy MgNd 30 , magnesium nickel intermediate alloy MgNi 30 , and refining agent (RJ-5 solvent), and preheat and dry the above materials in an environment at 120°C to remove the moisture in the raw materials;

[0075] 2) ZM5 ingot as smelting matrix, smelting under atmosphere (atmosphere is mixed gas of CO2 and SF6, volume ratio of the two is 99:1) protection, surface slagging when melt temperature is 730℃, then adding magnesium lanthanum intermediate alloy, magnesium neodymium intermediate alloy and magnesium nickel intermediate alloy into ZM5 melt for alloying and holding for 20 min, obtaining melt; using RJ-5 solvent for refining at 735℃ (adding amount of RJ-5 solvent is 7% of mass of melt), using argon for gas stirring for 5 min during refining, after refining, standing for 30 min, surface slagging when temperature drops to 685℃, then casting into magnesium alloy cast bar under inert atmosphere protection;

[0076] 3) homogenizing the magnesium alloy cast bar, homogenizing conditions are: 415±1℃×16h, air cooling to room temperature;

[0077] 4) processing the magnesium alloy ingot obtained in step 3) into bar material by hot extrusion, hot extrusion temperature is 375℃, extrusion ratio is 14, extrusion speed is 2mm / s;

[0078] 5) aging treatment for the extruded material prepared in step 4), aging treatment process parameters are 165±1℃×16h, air cooling to room temperature, obtaining soluble magnesium alloy material.

[0079] Comparative Example 1

[0080] A magnesium alloy material (extruded state)

[0081] The alloy is Mg-Al-Zn-Mn-Ni alloy, composed of the following mass percentages of elements: Mg balance, Al-9.2%, Zn-0.5%, Mn-0.25%, Ni-0.09%, i.e. Mg 89.96 Al 9.2 Zn 0.5 Mn 0.25 Ni 0.09 Alloy.

[0082] The preparation process comprises the following steps:

[0083] 1) according to the above element content ratio, weighing ZM5 ingot, magnesium nickel intermediate alloy MgNi 30 and refining agent (RJ-5 solvent), placing the above materials in 120℃ environment for preheating and drying, removing water in raw materials;

[0084] 2) ZM5 ingot as smelting matrix, smelting under atmosphere (atmosphere is CO2 and SF6 mixed gas, volume ratio of the two is 99:1), surface slagging when melt temperature is 730°C, then adding magnesium-nickel intermediate alloy into ZM5 melt for alloying and holding for 20 min, obtaining melt; using RJ-5 solvent for refining at 735°C (RJ-5 solvent is added in an amount of 7% of the mass of the melt), using argon for gas stirring for 5 min during refining, after refining, standing for 30 min, surface slagging when temperature drops to 685°C, then casting into magnesium alloy cast bar under inert atmosphere protection;

[0085] 3) Homogenizing the magnesium alloy cast bar, homogenizing conditions are: 415±1°C x 16h, air cooling to room temperature;

[0086] 4) Processing the magnesium alloy ingot obtained in step 3) into bar material by hot extrusion, hot extrusion temperature is 390°C, extrusion ratio is 14, extrusion speed is 1.4 mm / s, obtaining magnesium alloy material.

[0087] Comparative Example 2

[0088] A magnesium alloy material (extruded state + aged state)

[0089] The alloy is Mg-Al-Zn-Mn-Ni alloy, consisting of the following mass percentages of elements: Mg balance, Al-9.2%, Zn-0.5%, Mn-0.25%, Ni-0.09%, i.e. Mg 89.96 Al 9.2 Zn 0.5 Mn 0.25 Ni 0.09 Alloy.

[0090] The preparation process includes the following steps:

[0091] 1) According to the above element content ratio, weighing ZM5 ingot, magnesium-nickel intermediate alloy MgNi 30 and refining agent (RJ-5 solvent), placing the above materials in a 120°C environment for preheating and drying to remove water from the raw materials;

[0092] 2) ZM5 ingot as smelting base, smelting under atmosphere protection (atmosphere is mixed gas of CO2 and SF6, volume ratio of the two is 99:1), surface slagging when melt temperature is 730℃, then adding magnesium-nickel intermediate alloy into ZM5 melt for alloying and keeping for 20 min, obtaining melt; using RJ-5 solvent for refining at 735℃ (adding amount of RJ-5 solvent is 7% of mass of melt), using argon for gas stirring for 5 min during refining, after refining, standing for 30 min, surface slagging when temperature drops to 685℃, then casting into magnesium alloy cast bar under inert atmosphere protection;

[0093] 3) Homogenizing treatment of the magnesium alloy cast bar, homogenizing treatment condition is: 415±1℃×16h, air cooling to room temperature;

[0094] 4) Hot extrusion of the magnesium alloy ingot obtained in step 3) into bar material, hot extrusion temperature is 380℃, extrusion ratio is 14, extrusion speed is 1.5mm / s;

[0095] 5) Ageing treatment of the extruded material prepared in step 4), ageing treatment process parameter is 165±1℃×16h, air cooling to room temperature, obtaining magnesium alloy material.

[0096] Comparative Example 3

[0097] A soluble magnesium alloy material (extruded state + aged state)

[0098] The alloy is Mg-Al-Zn-Mn-La-Nd-Sr-Ni alloy, composed of the following mass percentages of elements: Mg balance, Al-8%, Zn-0.5%, Mn-0.25%, La-1%, Nd-0.45%, Sr-1.8%, Ni-0.22%, i.e. Mg 87.78 Al8Zn 0.5 Mn 0.25 La1Nd 0.45 Sr 1.8 Ni 0.22 alloy.

[0099] The preparation process comprises the following steps:

[0100] 1) According to the above element content ratio, weighing ZM5 ingot, magnesium-lanthanum intermediate alloy MgLa 30 , magnesium-neodymium intermediate alloy MgNd 30 , magnesium-nickel intermediate alloy MgNi 30 , metallic strontium and refining agent (RJ-5 solvent), placing the above materials in 120℃ environment for preheating and drying, removing water in raw materials;

[0101] 2) ZM5 ingot as smelting matrix, smelting under atmosphere protection (atmosphere is mixed gas of CO2 and SF6, volume ratio of the two is 99:1), surface slagging when melt temperature is 730℃, then adding magnesium lanthanum intermediate alloy, magnesium neodymium intermediate alloy, magnesium nickel intermediate alloy and metal strontium into ZM5 melt for alloying and holding for 20 min, to obtain melt; using RJ-5 solvent for refining at 735℃ (RJ-5 solvent is added in an amount of 7% of solution mass), using argon for gas stirring for 5 min during refining, after refining, standing for 30 min, surface slagging when temperature drops to 685℃, then casting into soluble magnesium alloy cast bar under inert atmosphere protection;

[0102] 3) homogenizing treatment of the soluble magnesium alloy cast bar, homogenizing treatment conditions are: 415±1℃×16h, air cooling to room temperature;

[0103] 4) processing the soluble magnesium alloy cast ingot obtained in step 3) into bar material by hot extrusion, hot extrusion temperature is 380℃, extrusion ratio is 14, extrusion speed is 2mm / s;

[0104] 5) aging treatment of the extruded material prepared in step 4), aging treatment process parameters are 165±1℃×16h, air cooling to room temperature, to obtain soluble magnesium alloy material.

[0105] Performance test:

[0106] Tensile strength (MPa), yield strength (MPa), elongation (%), Brinell hardness (HBW) and dissolution rate (mg / (cm 2 ·h) of the magnesium alloy prepared in example 1 and comparative examples 1-3 are tested.

[0107] Wherein:

[0108] 1) Tensile strength (MPa), yield strength (MPa) and elongation (%) are tested according to GB / T228-09 metal room temperature tensile test method.

[0109] 2) Brinell hardness is tested using a Brinell hardness tester, three parallel samples are used for each alloy, and the hardness test results are averaged.

[0110] 3) Dissolution rate (mg / (cm 2 ·h) is tested by weight loss method: taking The cylindrical sample of each group of alloy was weighed by an analytical balance (accuracy ±0.1 mg) to obtain the initial mass (W0) of the sample, and then the sample was immersed in a 3% KCl solution heated to 93°C and in a flowing state, the sample was kept at the same height during the immersion process, and the sample was kept 30-50 mm below the liquid surface, each sample was immersed for 0.5 h-5 h. The test corrosion product was placed in a stirred 200 g / L CrO3+10 g / L AgNO3 solution for 15-20 min, and when no bubbles were observed in the cleaning solution, the sample was taken out and immediately washed with water and the surface attachments were brushed off with a brush, and then the sample was dried and weighed, the mass of the sample after immersion was Wt. The dissolution rate (v) of the three groups of parallel samples after immersion corrosion was calculated using the following formula, and the average value was taken.

[0111]

[0112] wherein W0 is the mass (mg) of the sample before immersion, Wt is the weight (mg) of the sample after immersion and cleaning, A is the surface area (cm2) of the sample before immersion, and t is the immersion time (h). t 2 2

[0113] The mechanical properties and dissolution properties of the magnesium alloy material were determined, and the results are shown in Table 1.

[0114] Table 1

[0115]

[0116] As can be seen from Table 1, the tensile strength of the soluble magnesium alloy material prepared in Example 1 can reach 301.79 MPa, the yield strength can reach 197.3 MPa, the elongation can reach 10.8%, and the dissolution rate can reach 136 mg / (cm2·h). The mechanical properties of the magnesium alloy material prepared in Comparative Examples 1-2 are also excellent, but the dissolution rate is poor. After the addition of strontium in Comparative Example 3, although the dissolution rate is retained, the mechanical properties are significantly reduced.

[0117] Comparative Example 4

[0118] The same as Example 1, except that the content of Ni was adjusted to 0%, 0.05%, 0.1%, 0.15%, and 0.22%, respectively.

[0119] The mechanical properties and dissolution properties of the magnesium alloy material with different Ni contents were determined, and the results are shown in Table 2.

[0120] Table 2

[0121]

[0122] ​​​

[0123] From Table 2, it can be seen that when the Ni content is in the range of 0%-0.28%, the tensile strength, yield strength, dissolution and hardness increase with the increase of Ni content, but the elongation decreases slightly. When the Ni content is 0.28%, the tensile strength reaches 301.79 MPa, the yield strength reaches 197.3 MPa, the elongation is 10.8%, the hardness reaches 58.175 HBW, and the dissolution rate reaches 136 mg / (cm 2 ·h).

[0124] Comparative Example 5

[0125] The same as Example 1, except that the amount of La is adjusted to 0.15%, 0.3%, 0.7%, 1.3%, respectively.

[0126] The mechanical properties and dissolution properties of the magnesium alloy materials with different La contents are measured, and the results are shown in Table 3.

[0127] Table 3

[0128]

[0129] From Table 3, it can be seen that when the Nd content is 0.45% and the La content is in the range of 0.15%-1.3%, the tensile strength, yield strength and hardness increase first and then decrease with the increase of La content, the dissolution rate shows a decreasing trend, and the elongation shows an increasing trend. When the La content is 1%, the magnesium alloy material has excellent comprehensive mechanical properties: the tensile strength reaches 301.79 MPa, the yield strength reaches 197.3 MPa, the elongation is 10.8%, the hardness reaches 58.175 HBW, and the dissolution rate reaches 136 mg / (cm 2 ·h).

[0130] Comparative Example 6

[0131] The same as Example 1, except that the amount of Nd is adjusted to 3%, 1.5%, 0.7%, 0.4%, respectively.

[0132] The mechanical properties and dissolution properties of the magnesium alloy materials with different Nd contents are measured, and the results are shown in Table 4.

[0133] Table 4

[0134]

[0135]

[0136] As can be seen from Table 4, when the content of La is 0.45%, the content of Nd is in the range of 0.4%-3%, the tensile strength, yield strength, elongation, hardness increase first and then decrease with the increase of the content of Nd, and the dissolution rate presents a downward trend. When the content of Nd is 0.45%, the alloy has excellent comprehensive mechanical properties: the tensile strength reaches 301.79 MPa, the yield strength reaches 197.3 MPa, the elongation is 10.8%, the hardness reaches 58.175 HBW, and the dissolution rate reaches 136 mg / (cm 2 ·h).

[0137] The above merely illustrates the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A soluble magnesium alloy material, characterized in that, The soluble magnesium alloy material is Mg a Al b Zn c Mn d La e Nd f Ni g alloy, where, based on a + b + c + d + e + f + g = 100%, 7.5 wt.% < b < 10.0 wt.%, 0.2 wt.% < c < 0.8 wt.%, 0.15 wt.% < d < 0.5 wt.%, 0 wt.% < e < 1.15 wt.%, 0.35 wt.% < f < 0.65 wt.%, 0.05 wt.% < g < 0.3 wt.%, and the balance is a; The preparation method of the soluble magnesium alloy material includes the following steps: 1) Weigh out ZM5 ingots, magnesium-lanthanum master alloy, magnesium-neodymium master alloy, magnesium-nickel master alloy and refining agent by weight, and preheat them; 2) Under a protective atmosphere, the ZM5 ingot is used as the smelting matrix for smelting. After removing the slag from the surface, the magnesium-lanthanum master alloy, magnesium-neodymium master alloy, and magnesium-nickel master alloy are added to the ZM5 melt for alloying and held at a constant temperature to obtain a molten liquid. Subsequently, the refining agent is added to the molten liquid for refining. After standing and cooling, the slag is removed from the surface, and the molten liquid is cast into a soluble magnesium alloy rod under an inert atmosphere. 3) The soluble magnesium alloy casting rod is homogenized and hot extruded to obtain the soluble magnesium alloy material; The homogenization conditions described in step 3) are: temperature 415±1℃, time 16h, and air cooling to room temperature; The conditions for hot extrusion described in step 3) are: temperature 360-400℃, extrusion ratio 5-20, and extrusion speed 0.5-5mm / s.

2. A method for preparing the soluble magnesium alloy material as described in claim 1, characterized in that, Includes the following steps: 1) Weigh out ZM5 ingots, magnesium-lanthanum master alloy, magnesium-neodymium master alloy, magnesium-nickel master alloy and refining agent by weight, and preheat them; 2) Under a protective atmosphere, the ZM5 ingot is used as the smelting matrix for smelting. After removing the slag from the surface, the magnesium-lanthanum master alloy, magnesium-neodymium master alloy, and magnesium-nickel master alloy are added to the ZM5 melt for alloying and held at a constant temperature to obtain a molten liquid. Subsequently, the refining agent is added to the molten liquid for refining. After standing and cooling, the slag is removed from the surface, and the molten liquid is cast into a soluble magnesium alloy rod under an inert atmosphere. 3) The soluble magnesium alloy casting rod is homogenized and hot extruded to obtain the soluble magnesium alloy material.

3. The method for preparing the soluble magnesium alloy material according to claim 2, characterized in that, The atmosphere described in step 2) is a mixture of CO2 and SF6 in a volume ratio of 99:

1.

4. The method for preparing the soluble magnesium alloy material according to claim 2, characterized in that, The melting temperature in step 2) is 650-730℃, and the holding time is 10-60min.

5. The method for preparing the soluble magnesium alloy material according to claim 2, characterized in that, The refining process described in step 2) specifically includes: introducing argon gas into the melt, stirring at a temperature of 730-740℃ for 5-10 minutes, and letting it stand for 30-60 minutes after stirring; the amount of the refining agent is 2-10% of the total mass of the melt.

6. The method for preparing the soluble magnesium alloy material according to claim 2, characterized in that, The casting temperature described in step 2) is 680-700℃.

7. The method for preparing the soluble magnesium alloy material according to any one of claims 2-6, characterized in that, The hot extrusion process is followed by an aging treatment, the conditions of which are: temperature 165±1℃, time 16h, and air cooling to room temperature.

8. The application of the soluble magnesium alloy material as described in claim 1 in the field of temporary sealing materials.

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