Magnesium alloy and method for producing the same, vehicle component

Abstract

The application relates to a magnesium alloy and a preparation method and a vehicle part thereof, and the magnesium alloy comprises the following components in percentage of mass: 5-9% Al, 1.2-3.6% Zn, 0-0.35% Zr, 0-0.25% Sr, 0-0.3% Ca, 0-0.35% Sb, 0-0.15% Mn, 0-1.0% Sn, 0-1.0% Si, 0-1.5% Y, 0-0.8% La, 0-0.7% Sm, 0-1.1% Nd, 0-1.0% Gd, and the balance Mg; wherein the mass percentages of La, Nd, Y, Sm, Gd, Sr and Sb are all not 0. The application controls the synergistic effect of commonly used metals Al, Zn and specific types and proportions of rare earth elements by regulating the proportioning of specific components, so that the magnesium alloy has excellent high-temperature creep resistance and excellent mechanical strength.

Description

TECHNICAL FIELD

[0001] The present application relates to the alloy preparation technical field, and particularly relates to a magnesium alloy and a preparation method thereof and a vehicle part. BACKGROUND

[0002] The magnesium alloy has excellent physical properties such as light weight, high specific strength and high specific stiffness, is regarded as an ideal material for the light weight of an automobile, and the application amount is increased year by year. The application objects include but are not limited to: seat frame, CCB instrument panel frame, auxiliary instrument panel, instrument panel back plate, steering wheel frame and the like, and the endurance mileage can be greatly improved.

[0003] The room temperature strength of the traditional magnesium alloy material has basically reached the reliability requirement of mass-produced vehicle parts, and one of the main factors still restricting the popularization and application of the magnesium alloy in the automobile is that the high-temperature performance is unstable. For example, the general working temperature of the automobile transmission part is generally 150 DEG C to 250 DEG C, the heat is transferred to the external shell temperature which can still reach 120 DEG C to 150 DEG C, and the working precision needs to be controlled within 0.05 mm, but at high temperature, the movement speed of dislocation is accelerated, the deformation capacity of the magnesium alloy is enhanced, and the high-temperature creep phenomenon is prone to occur, thereby affecting the precision and service life of the part. In the traditional technology, the high-temperature creep resistance of the magnesium alloy is tried to be improved, but at the same time, the mechanical strength such as tensile strength and Vickers hardness of the magnesium alloy is reduced, and it is difficult to be applied to the vehicle body parts which need to serve at high temperature and have high strength requirements.

[0004] Therefore, the traditional technology still needs to be improved. SUMMARY

[0005] Based on this, the present application provides a magnesium alloy with excellent high-temperature creep resistance and excellent mechanical strength, a preparation method thereof and a vehicle part.

[0006] In one aspect of the present application, a magnesium alloy is provided, and the components of the magnesium alloy include, in percentage by mass: 5% to 9% Al, 1.2% to 3.6% Zn, 0 to 0.35% Zr, 0 to 0.25% Sr, 0 to 0.3% Ca, 0 to 0.35% Sb, 0 to 0.15% Mn, 0 to 1% Sn, 0 to 1% Si, 0 to 1.5% Y, 0 to 0.8% La, 0 to 0.7% Sm, 0 to 1.1% Nd, 0 to 1% Gd, and the balance Mg.

[0007] Among them, the mass percentages of La, Nd, Y, Sm, Gd, Sr and Sb are all not 0.

[0008] The magnesium alloy contains components in specific proportions, and the specific proportions of Zn and Al maximize the solid solution of Al elements to improve the mechanical strength of the magnesium alloy, the specific proportions of La, Nd, Y, Sm and Gd synergize with other non-rare earth metals to further improve the high-temperature creep resistance of the magnesium alloy, and the specific proportions of Sr and Sb synergize to realize uniform distribution of high-melting-point metal compounds in the alloy matrix, effectively improve the shape of high-temperature phases, and further improve the performance in the high-temperature zone. In this way, through the synergistic effect of specific proportions of commonly used metals such as Al and Zn and specific types and proportions of rare earth elements, the magnesium alloy has excellent high-temperature creep resistance and excellent mechanical strength.

[0009] In some embodiments, the mass ratio of Al and Zn is (2.5-4):1.

[0010] The proportions of Zn and Al are further adjusted to further improve the mechanical strength of the magnesium alloy.

[0011] In some embodiments, the sum of the mass percentages of La, Nd, Y, Sm and Gd is X1, and 0X1≤4.5%.

[0012] The proportions of La, Nd, Y, Sm and Gd are further adjusted to improve the synergistic effect with other non-rare earth metals and further improve the high-temperature creep resistance of the magnesium alloy.

[0013] In some embodiments, the sum of the mass percentages of Sr and Sb is X2, and 0X2≤0.5%.

[0014] The proportions of Sr and Sb are further controlled to further improve the performance in the high-temperature zone.

[0015] In some embodiments, the components of the magnesium alloy include, in terms of mass percentage: 5%-9% Al, 1.2%-3.6% Zn, 0.1%-0.35% Zr, 0.1%-0.25% Sr, 0.1%-0.3% Ca, 0.1%-0.35% Sb, 0.01%-0.15% Mn, 0.1%-1% Sn, 0.1%-1% Si, 0.1%-1.5% Y, 0.1%-0.8% La, 0.1%-0.7% Sm, 0.1%-1.1% Nd, 0.1%-1% Gd, and the balance Mg.

[0016] In some embodiments, the components of the magnesium alloy include, in terms of mass percentage: 5.5% Al, 2% Zn, 0.3% Zr, 0.1% Sr, 0.3% Ca, 0.2% Sb, 0.08% Mn, 0.5% Sn, 0.7% Si, 1.3% Y, 0.7% La, 0.5% Sm, 0.5% Nd, 1% Gd, and the balance Mg; or

[0017] The components of the magnesium alloy include, in terms of mass percentage, 7% Al, 2.6% Zn, 0.2% Zr, 0.2% Sr, 0.2% Ca, 0.2% Sb, 0.06% Mn, 0.7% Sn, 0.6% Si, 1.3% Y, 0.7% La, 0.5% Sm, 0.5% Nd, 1% Gd, and the balance Mg; or

[0018] The components of the magnesium alloy include, in terms of mass percentage, 8% Al, 2.5% Zn, 0.3% Zr, 0.3% Sr, 0.2% Ca, 0.2% Sb, 0.05% Mn, 0.4% Sn, 0.9% Si, 1.3% Y, 0.5% La, 0.6% Sm, 0.7% Nd, 0.8% Gd, and the balance Mg.

[0019] Another aspect of the present application provides a method for preparing a magnesium alloy, comprising the following steps:

[0020] Preparation raw materials are provided according to the stoichiometric ratio of the components of the magnesium alloy, and are melted into a melt;

[0021] The melt is sequentially subjected to a refining treatment, a standing treatment, and a forming treatment, to obtain a magnesium alloy.

[0022] In some embodiments, the method for preparing a magnesium alloy satisfies at least one of the following conditions (1) to (3):

[0023] (1) The temperature of the refining treatment is 706±2℃, and the time is 8min to 15min;

[0024] (2) The temperature of the standing treatment is 710±5℃, and the time is 10min to 30min;

[0025] (3) The forming treatment is compression molding.

[0026] In some embodiments, after the step of the refining treatment and before the step of the standing treatment, the method further comprises a step of performing a slagging treatment on the melt after the refining treatment; and / or

[0027] After the forming treatment, the method further comprises the following steps:

[0028] The product obtained by the forming treatment is sequentially subjected to a solid solution treatment and a stabilization treatment.

[0029] In some embodiments, the temperature of the solid solution treatment is 260℃ to 350℃, and the time is 10h to 18h; and / or

[0030] The temperature of the stabilizing treatment is 150-240°C and the time is 5-10 hours.

[0031] In another aspect of the present application, there is provided a vehicle component comprising the magnesium alloy or the magnesium alloy produced by the production method of the magnesium alloy. DETAILED DESCRIPTION

[0032] For the purpose of promoting an understanding of the principles of the application, reference will now be made to the embodiment illustrated in the drawings. The application will be described with respect to the preferred embodiment. However, the application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art.

[0033] Unless otherwise defined, 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. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0034] Terminology

[0035] Unless otherwise defined, or as the context requires, the terms used herein have the following meanings:

[0036] As used herein, the terms "and / or", "or / and", "and / or" are inclusive of any and all combinations of two or more associated listed items, and are inclusive of any and all combinations of the associated listed items, including any two of the associated listed items, any more of the associated listed items, or all of the associated listed items. It is noted that when at least two conjunctions selected from "and / or", "or / and", "and / or" are combined to connect at least three items, it should be understood that in this application, the technical solution undoubtedly includes the technical solution connected by "logical and", and also undoubtedly includes the technical solution connected by "logical or". For example, "A and / or B" includes three parallel solutions of A, B, and the combination of A and B. For another example, the technical solution of "A, and / or, B, and / or, C, and / or, D" includes any one of A, B, C, and D (i.e., the technical solution connected by "logical or"), and includes any and all combinations of A, B, C, and D, i.e., includes the combination of any two or any three of A, B, C, and D, and includes the four-item combination of A, B, C, and D (i.e., the technical solution connected by "logical and").

[0037] In the present application, "a plurality of", "a plurality of kinds", "a plurality of times" and the like, if not particularly limited, refer to more than two or equal to two in number. For example, "one or more" means one or more than two.

[0038] In the present application, the terms "first", "second", "third", "fourth" and the like in "first aspect", "second aspect", "third aspect", "fourth aspect" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the technical features indicated. Moreover, "first", "second", "third", "fourth" and the like only serve the purpose of non-exhaustive enumeration and description, and should be understood as not constituting a closed limitation on the quantity.

[0039] In the present application, among the technical features described in an open manner, a closed technical solution consisting of the enumerated features is also included, as well as an open technical solution including the enumerated features.

[0040] In the present application, with respect to a numerical interval (i.e. a numerical range), if not particularly stated, the distribution of the optional values within the numerical interval is considered to be continuous, and includes both numerical end points (i.e. the minimum value and the maximum value) of the numerical interval, as well as every value between the two numerical end points. If not particularly stated, when a numerical interval refers only to integers within the numerical interval, including both end point integers of the numerical range, as well as every integer between the two end points, it is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe a feature or property, these numerical ranges can be combined. In other words, unless otherwise indicated, the numerical ranges disclosed herein are to be interpreted as including any and all sub-ranges therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. The "numerical interval" is allowed to broadly include numerical interval types such as percentage interval, ratio interval, ratio interval, etc.

[0041] In the present application, the temperature parameter, if not particularly limited, allows for constant temperature treatment, as well as for variations within a certain temperature interval. It should be understood that the constant temperature treatment allows for fluctuations within the accuracy range controlled by the instrument. Fluctuations within a range such as ±5°C, ±4°C, ±3°C, ±2°C, ±1°C are allowed.

[0042] In the present application, "room temperature" or "ambient temperature" refers to 10°C to 35°C, further to 20°C to 30°C.

[0043] The mass or weight of the related components mentioned in the embodiment of the present application can not only refer to the specific content of each component, but also represent the proportional relationship between the mass or weight of each component. Therefore, as long as the content of the related components in the embodiment of the present application is enlarged or reduced in proportion, it is within the scope disclosed in the embodiment of the present application. Specifically, the mass or weight mentioned in the embodiment of the present application can be μg, mg, g, kg and other units commonly known in the chemical field.

[0044] An embodiment of the present application provides a magnesium alloy. The components of the magnesium alloy include, in percentage by mass: 5-9% of Al, 1.2-3.6% of Zn, 0-0.35% of Zr, 0-0.25% of Sr, 0-0.3% of Ca, 0-0.35% of Sb, 0-0.15% of Mn, 0-1.0% of Sn, 0-1.0% of Si, 0-1.5% of Y, 0-0.8% of La, 0-0.7% of Sm, 0-1.1% of Nd, 0-1.0% of Gd, and the balance of Mg.

[0045] The mass percentages of La, Nd, Y, Sm, Gd, Sr and Sb are all not 0.

[0046] The magnesium alloy contains components with specific proportions. The specific proportions of Zn and Al enable the solid solution of Al elements to be maximized, so as to improve the mechanical strength of the magnesium alloy. The specific proportions of La, Nd, Y, Sm and Gd and other non-rare earth metals synergistically improve the high-temperature creep resistance of the magnesium alloy. The specific proportions of Sr and Sb can synergistically realize uniform particle distribution of high-melting-point metal compounds in the alloy matrix, effectively improve the shape of the high-temperature phase, and further improve the performance in the high-temperature zone. In this way, the specific proportions of the commonly used metals Al and Zn and the specific types and proportions of rare earth elements synergistically work, so that the magnesium alloy has excellent high-temperature creep resistance and excellent mechanical strength.

[0047] In some embodiments, the components of the magnesium alloy include, in percentage by mass: 5-9% of Al, 1.2-3.6% of Zn, 0.1-0.35% of Zr, 0.1-0.25% of Sr, 0.1-0.3% of Ca, 0.1-0.35% of Sb, 0.01-0.15% of Mn, 0.1-1.0% of Sn, 0.1-1.0% of Si, 0.1-1.5% of Y, 0.1-0.8% of La, 0.1-0.7% of Sm, 0.1-1.1% of Nd, 0.1-1% of Gd, and the balance of Mg.

[0048] The mass percentage of Al is "5% to 9%", and the mass percentage of Al includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values in the embodiments and the following point values: 5%, 6%, 7%, 8%, 9%; or a range composed of any two numerical values.

[0049] The mass percentage of Zn is "1.2% to 3.6%", and the mass percentage of Zn includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values in the embodiments and the following point values: 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, or a range composed of any two numerical values.

[0050] The mass percentage of Zr is "0.1% to 0.35%", and the mass percentage of Zr includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values in the embodiments and the following point values: 0.1%, 0.15%, 0.2%, 0.21%, 0.25%, 0.3%, 0.31%, 0.35%; or a range composed of any two numerical values.

[0051] The mass percentage of Sr is "0 to 0.25%", and the mass percentage of Sr includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values in the embodiments and the following point values: 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.1%, 0.13%, 0.14%, 0.15%, 0.2%, 0.23%, 0.24%, 0.25%; or a range composed of any two numerical values.

[0052] The mass percentage of Ca is "0 to 0.3%", and the mass percentage of Ca includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values in the embodiments and the following point values: 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.1%, 0.13%, 0.14%, 0.15%, 0.2%, 0.23%, 0.24%, 0.25%, 0.3%; or a range composed of any two numerical values.

[0053] The mass percentage of Sb is 0-0.35%, and the mass percentage of Sb includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include but are not limited to the point values in the embodiments and the following point values: 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.1%, 0.13%, 0.14%, 0.15%, 0.2%, 0.23%, 0.24%, 0.25%, 0.3%, 0.35%; or a range composed of any two numerical values.

[0054] The mass percentage of Mn is 0-0.15%, and the mass percentage of Mn includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include but are not limited to the point values in the embodiments and the following point values: 0, 0.05%, 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%; or a range composed of any two numerical values.

[0055] The mass percentage of Sn is 0-1%, and the mass percentage of Sn includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include but are not limited to the point values in the embodiments and the following point values: 0, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%; or a range composed of any two numerical values.

[0056] The mass percentage of Si is 0-1%, and the mass percentage of Si includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include but are not limited to the point values in the embodiments and the following point values: 0, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%; or a range composed of any two numerical values.

[0057] The mass percentage of Y is 0-1.5%, and the mass percentage of Y includes the minimum and maximum values of the range, and every value between the minimum and maximum values. Specific examples include but are not limited to the point values in the embodiments and the following point values: 0, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%; or a range composed of any two numerical values.

[0058] The mass percentage of La is 0-0.8%, and the mass percentage of La includes the minimum and maximum values in the range, and every value between the minimum and maximum values, and specific examples include but are not limited to the point values in the embodiments and the following point values: 0, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%; or a range composed of any two numerical values.

[0059] The mass percentage of Sm is 0-0.7%, and the mass percentage of Sm includes the minimum and maximum values in the range, and every value between the minimum and maximum values, and specific examples include but are not limited to the point values in the embodiments and the following point values: 0, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%; or a range composed of any two numerical values.

[0060] The mass percentage of Nd is 0-1.1%, and the mass percentage of Nd includes the minimum and maximum values in the range, and every value between the minimum and maximum values, and specific examples include but are not limited to the point values in the embodiments and the following point values: 0, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%; or a range composed of any two numerical values.

[0061] The mass percentage of Gd is 0-1%, and the mass percentage of Gd includes the minimum and maximum values in the range, and every value between the minimum and maximum values, and specific examples include but are not limited to the point values in the embodiments and the following point values: 0, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%; or a range composed of any two numerical values.

[0062] It should be noted that under the limitation of the existing process conditions, other elements different from the target composition elements of the magnesium alloy may be introduced due to the purity of raw materials or the preparation environment, which are called impurity elements.

[0063] Further, the impurity elements include one or more of Cu, Fe, and Ni; further, the impurity elements are ≤0.15% according to the mass percentage.

[0064] In some embodiments, the components of the magnesium alloy include, in percentage by mass: 5% to 9% Al, 1.2% to 3.6% Zn, 0.1% to 0.35% Zr, 0.1% to 0.25% Sr, 0.1% to 0.3% Ca, 0.1% to 0.35% Sb, 0.01% to 0.15% Mn, 0.1% to 1% Sn, 0.1% to 1% Si, 0.1% to 1.5% Y, 0.1% to 0.8% La, 0.1% to 0.7% Sm, 0.1% to 1.1% Nd, 0.1% to 1% Gd, and the balance Mg.

[0065] In some embodiments, the mass ratio of Al and Zn is (2.5 to 4): 1.

[0066] Further regulating the ratio of Zn and Al components further improves the mechanical strength of the magnesium alloy.

[0067] The mass ratio of Al and Zn is (2.5 to 4): 1, including the minimum and maximum values of the range, and every value between the minimum and maximum values, and specific examples include but are not limited to the point values in the embodiments and the following point values: 2.5:1, 2.6:1, 2.7:1, 2.8:1, 2.9:1, 3:1, 3.2:1, 3.5:1, 3.6:1, 3.7:1, 3.8:1, 3.9:1, 4:1; or a range composed of any two numerical values.

[0068] In some embodiments, the sum of the mass percentages of La, Nd, Y, Sm, and Gd is X1, and 0 < X1 ≤ 4.5%.

[0069] The above 0 < X1 ≤ 4.5% includes the minimum and maximum values of the range, and every value between the minimum and maximum values, and specific examples include but are not limited to the point values in the embodiments and the following point values: 4.5%, 4.4%, 4.3%, 4.2%, 4.1%, 4%, 3.7%, 3.6%, 3.5%, 3.4%, 3.3%, 3.2%, 3.1%, 3%, 2.7%, 2.6%, 2.5%, 2.4%, 2.3%, 2.2%, 2.1%, 2%, 1.7%, 1.6%, 1.5%, 1.4%, 1.3%, 1.2%, 1.1%, 1%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, 0.1%; or a range composed of any two numerical values.

[0070] In some embodiments, the sum of the mass percentages of La, Nd, Y, Sm, and Gd is X1, and 2% ≤ X1 ≤ 4.5%.

[0071] Further regulate the proportion of La, Nd, Y, Sm and Gd, improve the synergistic effect with other non-rare earth metals, and further improve the high temperature creep resistance of the magnesium alloy.

[0072] In some embodiments, the sum of the mass percentages of Sr and Sb is X2, and 0

[0073] The above 0

[0074] Further control the component ratio of Sr and Sb to further improve the performance in the high temperature zone.

[0075] In some embodiments, 0.3≤X2≤0.5%.

[0076] In some embodiments, the components of the magnesium alloy include, in terms of mass percentage: 5.5% Al, 2% Zn, 0.3% Zr, 0.1% Sr, 0.3% Ca, 0.2% Sb, 0.08% Mn, 0.5% Sn, 0.7% Si, 1.3% Y, 0.7% La, 0.5% Sm, 0.5% Nd, 1% Gd, and the balance Mg.

[0077] In some embodiments, the components of the magnesium alloy include, in terms of mass percentage: 7% Al, 2.6% Zn, 0.2% Zr, 0.2% Sr, 0.2% Ca, 0.2% Sb, 0.06% Mn, 0.7% Sn, 0.6% Si, 1.3% Y, 0.7% La, 0.5% Sm, 0.5% Nd, 1% Gd, and the balance Mg.

[0078] In some embodiments, the components of the magnesium alloy include, in terms of mass percentage: 8% Al, 2.5% Zn, 0.3% Zr, 0.3% Sr, 0.2% Ca, 0.2% Sb, 0.05% Mn, 0.4% Sn, 0.9% Si, 1.3% Y, 0.5% La, 0.6% Sm, 0.7% Nd, 0.8% Gd, and the balance Mg.

[0079] In another aspect of the present application, a method for preparing a magnesium alloy is provided, including the following steps S10-S20.

[0080] S10, providing raw materials according to the stoichiometric ratio of the components of the magnesium alloy, and smelting to form a melt.

[0081] In some embodiments, the melting is performed in a protective atmosphere, and the protective gas comprises SF6 and CO2.

[0082] In some embodiments, the melting comprises a melting process and a holding process, the temperature of the melting process is 695±5℃, and the temperature of the holding process is 705±5℃.

[0083] In some embodiments, the raw materials comprise pure Mg, pure Al, Mg-45Zn intermediate alloy, Mg-30Zr intermediate alloy, Mg-20Sr intermediate alloy, Mg-20Ca intermediate alloy, Mg-Sb intermediate alloy, Mg-10Mn intermediate alloy, Mg-Sn intermediate alloy, Mg-13Si intermediate alloy, Mg-20Y intermediate alloy, Mg-La intermediate alloy, Mg-30Sm intermediate alloy, Mg-20Nd intermediate alloy, and Mg-30Gd intermediate alloy.

[0084] In some embodiments, before the melting, the method further comprises the steps of sequentially performing oil removal and sandblasting on the pure Mg and the pure Al ingot.

[0085] In some embodiments, the melting comprises the following steps:

[0086] The pure Mg is melted in a protective atmosphere, and pure Al, Mg-45Zn intermediate alloy, Mg-20Sr intermediate alloy, Mg-20Ca intermediate alloy, Mg-Sb intermediate alloy, and Mg-Sn intermediate alloy are added to the Mg liquid after melting. After all the raw materials are melted, Mg-10Mn intermediate alloy, Mg-30Zr intermediate, Mg-13Si intermediate alloy, Mg-20Y intermediate alloy, Mg-La intermediate alloy, Mg-30Sm intermediate alloy, Mg-20Nd intermediate alloy, and Mg-30Gd intermediate alloy are added. After all the above alloys are melted, the temperature of the melt is raised to keep the temperature at 705±5℃.

[0087] S20, the melt is sequentially subjected to a refining process, a standing process, and a forming process to obtain a magnesium alloy.

[0088] In some embodiments, the temperature of the refining process is 706±2℃, and the time is 8min-15min.

[0089] In some embodiments, the refining process is performed under the action of a modifier; further, the modifier can be various modifiers commonly used in the art, such as C2Cl6.

[0090] In some embodiments, the amount of the modifier added is (1.4±0.2)‰ of the mass of the melt.

[0091] In some embodiments, the argon supplemental purging is performed by swing purging equipment during the refining process. In this way, the melt can be further purified.

[0092] In some embodiments, the refining process is followed by a slagging process of the refined melt before the resting process.

[0093] In some embodiments, the resting process is performed at a temperature of 710±5℃ for a time period of 10min-30min.

[0094] In some embodiments, the forming process is performed by compression molding. Alternatively, the compression molding includes, but is not limited to, die casting.

[0095] In some embodiments, the melt is transferred before the die casting. The melt is transferred through a transfer pipe into a pouring furnace beside the die casting machine. Alternatively, the melt is first poured into an ingot, then remelted in a quantitative furnace, and then subjected to the die casting.

[0096] In some embodiments, the die casting is performed by high vacuum die casting.

[0097] The high vacuum die casting includes the following steps in sequence: mold closing, vacuum pumping, quantitative pouring, die casting, mold opening and part taking. Further, before the quantitative pouring, the vacuum degree in the mold cavity is controlled to be 40mbar, the mold temperature is (150-170)℃, the mold gate ratio is 30:1, the gate step length is (1-1.5)mm, the slow injection rate is (0.13-0.26)m / s, and the fast injection rate is (3.17-3.58)m / s.

[0098] In some embodiments, the forming process is followed by the following steps:

[0099] The product obtained by the forming process is subjected to the following steps in sequence: solution treatment and stabilization treatment.

[0100] In some embodiments, the solution treatment is performed at a temperature of 260-350℃ for a time period of 10-18h.

[0101] In some embodiments, the solution-treated product is subjected to air cooling after the solution treatment and before the stabilization treatment. Further, the air cooling is performed by placing the product in air for a time period of (10-30)min.

[0102] In some embodiments, the stabilization treatment is performed at a temperature of 150-240℃ for a time period of 5-10h.

[0103] In some embodiments, after the step of stabilizing treatment, a step of air cooling the product after the stabilizing treatment is further included. Further, the air cooling is performed by placing the product in air for (5-15) min.

[0104] In another embodiment of the present application, a vehicle part is provided, which comprises the magnesium alloy or the magnesium alloy prepared by the method as described above.

[0105] The magnesium alloy has excellent high-temperature creep resistance and excellent mechanical strength, and can meet the performance requirements of various complex vehicle parts.

[0106] In some embodiments, the vehicle part includes, but is not limited to, at least one of a gearbox housing, a seat skeleton, a CCB instrument panel skeleton, an auxiliary instrument panel, an instrument panel back plate, and a steering wheel skeleton.

[0107] The present application will be described in detail below with reference to specific embodiments, but the present application is not limited to the following embodiments. It should be understood that the appended claims define the scope of the present application, and those skilled in the art should realize that certain changes to the embodiments of the present application will be covered by the spirit and scope of the claims.

[0108] The following are specific embodiments.

[0109] Embodiment 1

[0110] (1) The raw materials are prepared according to the stoichiometric ratio of the components of the magnesium alloy in Table 1, which include pure Mg, pure Al, Mg-45Zn intermediate alloy, Mg-30Zr intermediate alloy, Mg-20Sr intermediate alloy, Mg-20Ca intermediate alloy, Mg-Sb intermediate alloy, Mg-10Mn intermediate alloy, Mg-Sn intermediate alloy, Mg-13Si intermediate alloy, Mg-20Y intermediate alloy, Mg-La intermediate alloy, Mg-30Sm intermediate alloy, Mg-20Nd intermediate alloy, and Mg-30Gd intermediate alloy. The pure magnesium and pure aluminum ingots are used after oil removal, sandblasting, and drying.

[0111] (2) Pure Mg is melted under a protective atmosphere (SF6 and CO2), and after melting, pure Al, Mg-45Zn master alloy, Mg-20Sr master alloy, Mg-20Ca master alloy, Mg-Sb master alloy and Mg-Sn master alloy are added into the Mg liquid. After the raw materials are completely melted, Mg-10Mn master alloy, Mg-30Zr master alloy, Mg-13Si master alloy, Mg-20Y master alloy, Mg-La master alloy, Mg-30Sm master alloy, Mg-20Nd master alloy and Mg-30Gd master alloy are added. After the above-mentioned alloys are completely melted, the temperature of the melt is kept at 705±5℃.

[0112] (3) C2Cl6 modifier is added into the melt to adjust the temperature to (706±2)℃ for refining treatment, which lasts for 10 min. The addition amount of the modifier is 1.5‰ of the mass of the melt. Argon is supplemented and washed to further purify the melt by swinging blowing equipment. Then, slagging treatment is performed, and then the temperature is increased to 710±5℃ and kept for 10 min. Finally, high-vacuum die casting is performed. The process sequence is as follows: mold closing, vacuum pumping, quantitative pouring, die casting, mold opening and piece taking. The high-vacuum die casting technology is as follows: before quantitative pouring, the vacuum degree in the mold cavity is controlled to be 40 mbar, the mold temperature is 170℃, the mold gate ratio is 30:1, the gate step length is 1.5 mm, the slow injection rate is 0.26 m / s, and the fast injection rate is 3.58 m / s. After mold opening and piece taking, solution treatment is performed at 350℃ for 10 h, and then the piece is placed in air for 10 min for air cooling. Then, stabilization treatment is performed at 240℃ for 5 h, and then the piece is placed in air for 5 min. Thus, the magnesium alloy is obtained.

[0113] (4) Performance test:

[0114] 1: Tensile test: the tensile property of the magnesium alloy is tested at room temperature (25℃) according to GB / T228.1 standard. The tensile strength, yield strength and elongation test results are shown in Table 2.

[0115] 2: Hardness test: the hardness of the magnesium alloy is tested at room temperature (25℃) according to GB / T 231.1 standard. The Brinell hardness test results are shown in Table 2.

[0116] 3: High-temperature creep test: the magnesium alloy is placed at a high temperature of 150℃, and the strain amount is set to be 0.2%. The final specified plastic creep strength is measured. The specific value is shown in Table 2.

[0117] Examples 2-5

[0118] Examples 2-5 are basically the same as Example 1, except that the stoichiometric ratio of the components of the magnesium alloy in step (1) is different from that of Example 1. For details, see Table 1.

[0119] Other steps and process conditions are the same as those in Example 1, and the test results are shown in Table 2.

[0120] Comparative Examples 1-9

[0121] Comparative Examples 1-9 are basically the same as Example 1, except that the stoichiometric ratios of the components of the magnesium alloy in step (1) are different from those in Example 1, as shown in Table 1.

[0122] Other steps and process conditions are the same as those in Example 1, and the test results are shown in Table 2.

[0123] The compositions of the magnesium alloys in each of the examples and comparative examples are shown in Table 1.

[0124] Table 1

[0125]

[0126] The performance results of the magnesium alloys in each of the examples and comparative examples are shown in Table 2.

[0127] Table 2

[0128]

[0129] As can be seen from the data in Tables 1-2, by adjusting the proportions of each specific component, controlling the synergistic effect of commonly used metals Al, Zn, etc. and specific types and proportions of rare earth elements, the magnesium alloy has excellent high-temperature creep resistance and excellent mechanical strength.

[0130] The technical features of the above-described examples can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described examples are described, however, as long as the combinations of the technical features do not contradict each other, they should be considered within the scope of the present disclosure.

[0131] The above-described examples only express several embodiments of the present application, and the description is relatively specific and detailed, but it should not be construed as limiting the scope of the patent. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the scope of protection of the present application should be subject to the appended claims.

Claims

1. A magnesium alloy characterized by comprising, in mass %, The magnesium alloy comprises, by mass percent: 5-9% Al, 1.3-3.6% Zn, 0.1-0.35% Zr, 0.1-0.25% Sr, 0.1-0.3% Ca, 0.1-0.35% Sb, 0.01-0.15% Mn, 0.1-1% Sn, 0.1-1% Si, 0.1-1.5% Y, 0.1-0.7% La, 0.1-0.7% Sm, 0.1-1.1% Nd, 0.1-1% Gd, and the balance Mg; wherein the sum of the mass percentages of La, Nd, Y, Sm and Gd is X1, and 2%≤X1≤4.5%.

2. The magnesium alloy according to claim 1, wherein The mass ratio of Al to Zn is (2.5-4):

1.

3. The magnesium alloy according to claim 1, wherein The sum of the mass percentages of La, Nd, Y, Sm and Gd is X1, and 3.1%≤X1≤4.5%.

4. The magnesium alloy according to any one of claims 1 to 3, wherein The sum of the mass percentages of Sr and Sb is X2, and 0X2≤0.5%.

5. The magnesium alloy according to any one of claims 1 to 3, wherein The magnesium alloy comprises, by mass percent: 5-9% Al, 1.3-3.5% Zn, 0.1-0.35% Zr, 0.1-0.25% Sr, 0.1-0.3% Ca, 0.2-0.35% Sb, 0.05-0.15% Mn, 0.4-1.0% Sn, 0.3-1.0% Si, 0.3-1.3% Y, 0.3-0.7% La, 0.5-0.7% Sm, 0.5-1.1% Nd, 0.8-1% Gd, and the balance Mg.

6. The magnesium alloy according to any one of claims 1 to 3, wherein The magnesium alloy comprises, by mass percent: 5-9% Al, 1.3-3.5% Zn, 0.1-0.35% Zr, 0.1-0.25% Sr, 0.1-0.3% Ca, 0.2-0.35% Sb, 0.05-0.15% Mn, 0.4-1.0% Sn, 0.3-1.0% Si, 0.3-1.3% Y, 0.3-0.7% La, 0.5-0.7% Sm, 0.5-1.1% Nd, 0.8-1% Gd, and the balance Mg. The magnesium alloy comprises, by mass percent: 5-9% Al, 1.3-3.5% Zn, 0.1-0.35% Zr, 0.1-0.25% Sr, 0.1-0.3% Ca, 0.2-0.35% Sb, 0.05-0.15% Mn, 0.4-1.0% Sn, 0.3-1.0% Si, 0.3-1.3% Y, 0.3-0.7% La, 0.5-0.7% Sm, 0.5-1.1% Nd, 0.8-1% Gd, and the balance Mg. The magnesium alloy comprises, by mass percent: 5-9% Al, 1.3-3.5% Zn, 0.1-0.35% Zr, 0.1-0.25% Sr, 0.1-0.3% Ca, 0.2-0.35% Sb, 0.05-0.15% Mn, 0.4-1.0% Sn, 0.3-1.0% Si, 0.3-1.3% Y, 0.3-0.7% La, 0.5-0.7% Sm, 0.5-1.1% Nd, 0.8-1% Gd, and the balance Mg.

7. A method of producing a magnesium alloy, characterized by, The method comprises the following steps: The stoichiometric ratio of the components of the magnesium alloy according to any one of claims 1-6 is used to provide raw materials for preparation, and the raw materials are melted into a melt; The melt is sequentially subjected to a refining treatment, a standing treatment and a forming treatment to obtain a magnesium alloy.

8. The method of producing a magnesium alloy according to claim 7, characterized by, The preparation method satisfies at least one of the following (1)-(3): (1) the temperature of the refining treatment is 706±2℃, and the time is 8min~15min; (2) the temperature of the standing treatment is 710±5℃, and the time is 10min~30min; (3) the forming treatment adopts press forming.

9. The method of producing a magnesium alloy according to any one of claims 7 to 8, characterized by, After the step of the refining treatment and before the step of the standing treatment, the method further comprises a step of performing a slagging treatment on the melt after the refining treatment; and / or After the step of the forming treatment, the method further comprises a step of: performing a solid solution treatment and a stabilization treatment on the product obtained in the step of the forming treatment in sequence.

10. The method of producing a magnesium alloy according to claim 9, wherein The temperature of the solid solution treatment is 260℃~350℃, and the time is 10h~18h; and / or The temperature of the stabilization treatment is 150℃~240℃, and the time is 5h~10h.

11. A vehicle component, characterized by The vehicle part comprises the magnesium alloy according to any one of claims 1~6 or the magnesium alloy prepared by the method according to any one of claims 7~10.

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