Mg-y-auc alloy containing long-period stacking ordered phase and preparation method thereof

Abstract

The application discloses a Mg-Y-Au alloy containing long-period stacking ordered phases and a preparation method thereof, and belongs to the technical field of metal materials. The atomic percentage of each component of the Mg-Y-Au alloy is as follows: Y 1-10 at.%, Au 1-10 at.%, and the balance is Mg; the Mg-Y-Au alloy contains long-period stacking ordered phases with 18R structure, the stacking sequence of the long-period stacking ordered phases is ABABABCACACABCBCBC, and the period length is 4.69+ / -0.5 nm. The preparation method is as follows: raw materials are put into a crucible of a smelting furnace according to a proportion to be melted, and after being melted, the Mg-Y-Au alloy is cooled and formed into a shape while being supplied with a protective gas. The application proves a new element combination capable of forming long-period stacking ordered phases in a magnesium alloy by reasonably selecting alloy elements Y and Au, and provides more choices for the design and development of long-period stacking ordered magnesium alloys.

Description

Technical Field

[0001] This invention belongs to the field of metallic materials, specifically relating to a Mg-Y-Au alloy containing a long-period stacked ordered phase and its preparation method. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] In 2001, Kawamura et al. (Y. Kawamura, et al. Materials Transactions 42(2001)1172-1176) first prepared Mg with a yield strength of over 600 MPa using a rapid solidification powder metallurgy process. 97 The Zn1Y2 alloy, and subsequent work (E.Abe, et al. Acta Materialia 50 (2002) 3845-3857) proved that its excellent mechanical properties are due to the long-period stacked ordered phase with high-density stacking faults distributed in the alloy.

[0004] Long-period stacked ordered phases, as effective strengthening and toughening phases, can significantly improve the strength, elongation, creep resistance, and corrosion resistance of magnesium alloys. Currently, the Mg-Y alloys experimentally confirmed to contain long-period stacked ordered phases include Mg-Y-Co (S.-B.Mi, et al. Scripta Materialia 68 (2013) 635–638), Mg-Y-Ni (K.Ma, et al. Materials Characterization 181 (2021) 111489), Mg-Y-Cu (Y.Kawamura, et al. Scripta Materialia 55 (2006) 453–456), and Mg-Y-Zn (E.Abe, et al. Acta Materialia 50 (2002) 3845–3857). However, there are no reports confirming that Mg-Y-Au alloys contain long-period stacked ordered phases. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a Mg-Y-Au alloy containing a long-period stacked ordered phase and its preparation method. The inventors, through the rational selection of alloying elements and experimental determination, have demonstrated that a long-period stacked ordered phase can also be formed in the Mg-Y-Au alloy, providing more options for the design and development of magnesium alloys with long-period stacked ordered phases.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides a Mg-Y-Au alloy containing a long-period stacked ordered phase, wherein the atomic percentage of each component of the Mg-Y-Au alloy is: Y 1-10 at.%, Au 1-10 at.%, with the balance being Mg;

[0008] The Mg-Y-Au alloy contains a long-period stacked ordered phase with an 18R structure, whose stacking sequence is ABABABCACACABCBCBC, and the period length is 4.69±0.5nm.

[0009] The role of Au is to work with Mg and Y to generate a ternary long-period stacked ordered phase.

[0010] In some embodiments of the present invention, the Mg-Y-Au alloy comprises a Mg matrix, a long-period stacked ordered phase, and Mg. 24 Y5 phase, a long-period stacked ordered phase, mostly grows in the Mg matrix and Mg2+. 24 Between the Y5 phases, by Mg 24 Y5 grows into the Mg matrix.

[0011] In some embodiments of the present invention, the atomic percentage of each component of the Mg-Y-Au alloy is: Y 5 at.%, Au 2.5 at.%, with the balance being Mg.

[0012] In some embodiments of the present invention, the atomic percentage of each component of the Mg-Y-Au alloy is: Y 1 at.%, Au 1 at.%, with the balance being Mg.

[0013] In some embodiments of the present invention, the atomic percentage of each component of the Mg-Y-Au alloy is: Y 10 at.%, Au 10 at.%, with the balance being Mg.

[0014] A second aspect of the present invention provides a method for preparing the above-mentioned Mg-Y-Au alloy containing a long-period stacked ordered phase, comprising the following steps:

[0015] Pure Mg, Mg-Y master alloy and pure Au were placed in a crucible in a certain proportion and melted in a vacuum induction melting furnace. After the raw materials were completely melted, heating was stopped, and the mixture was left to stand in the melting furnace while a protective gas was introduced. After the melt was completely solidified, it was cooled to room temperature.

[0016] In some embodiments of the present invention, a vacuum system is used to evacuate the furnace to a vacuum state before melting in a vacuum induction melting furnace.

[0017] In some embodiments of the present invention, during smelting, heating is used to completely melt the raw materials, accompanied by electromagnetic stirring.

[0018] In some embodiments of the present invention, the melting temperature is 700°C and the melting time is 1 minute.

[0019] In some embodiments of the present invention, the protective gas includes, but is not limited to, argon, carbon dioxide or sulfur hexafluoride, preferably argon.

[0020] The beneficial effects of this invention are as follows:

[0021] This invention provides a novel magnesium alloy Mg-Y-Au containing a long-period stacked ordered phase. By rationally selecting alloying elements and through experiments, the inventors have determined that a long-period stacked ordered phase can also be formed in the Mg-Y-Au alloy, providing more options for the design and development of magnesium alloys with long-period stacked ordered phases.

[0022] The novel magnesium alloy Mg-Y-Au containing a long-period stacked ordered phase provided by this invention has the advantages of readily available and easily stored raw materials and a simple preparation method. Attached Figure Description

[0023] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0024] Figure 1 This is a SEM image of the as-cast alloy in Example 1 of the present invention;

[0025] Figure 2 This is a SEM image of the as-cast alloy after etching in Example 1 of the present invention;

[0026] Figure 3 The SAED pattern of the as-cast alloy in Embodiment 1 of the present invention;

[0027] Figure 4 This is a TEM image of the as-cast alloy in Example 1 of the present invention;

[0028] Figure 5 This is a SEM image of the as-cast alloy in Example 2 of the present invention;

[0029] Figure 6 This is a SEM image of the as-cast alloy in Example 3 of the present invention;

[0030] Figure 7 The image shows the SEM image of the as-cast alloy in Comparative Example 1. Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0032] Example 1

[0033] Using pure Mg and Mg-Y master alloys with a purity greater than 99.99 wt.%, and pure Au with a purity greater than 99.99 wt.%, according to Mg 92.5 Y5Au 2.5 The alloy is smelted according to the (atomic fraction) alloy composition ratio.

[0034] During smelting, all raw materials are placed together in a corundum crucible, which is then placed in a vacuum induction melting furnace. First, the furnace is evacuated using a vacuum system. Under this vacuum, the materials are heated until completely melted, accompanied by electromagnetic stirring. The melting temperature is 700℃, and the melting time is 1 minute.

[0035] After the raw materials are completely melted, heating is stopped and the cooling process begins. During this process, Ar gas is introduced for protection, and the melt is cooled to room temperature after it has completely solidified.

[0036] Mg was thus obtained. 92.5 Y5Au 2.5 The as-cast alloy, the polished surface of which was observed by scanning electron microscopy as follows: Figure 1 As shown in the figure. After etching with 2% oxalic acid, the samples were observed using a scanning electron microscope. The results are as follows. Figure 2 As shown, the as-cast Mg 92.5 Y5Au 2.5 The alloy comprises a Mg matrix, a long-period stacked ordered phase, and Mg 24 Y5 phase, a long-period stacked ordered phase composed of Mg 24 Y5 grows into the Mg matrix.

[0037] The Mg 92.5 Y5Au 2.5 Selected area diffraction patterns of long-period stacked ordered phases in alloys, such as Figure 3 As shown, the existence of this long-period stacked ordered phase is confirmed, and the structure is 18R.

[0038] Figure 4 For this Mg 92.5 Y5Au 2.5 Transmission electron microscopy (TEM) images of the as-cast alloy confirmed that the stacking sequence in the long-period stacked ordered phase of the 18R structure is ABABABCACACABCBCBC, with a period length of approximately 4.69 nm.

[0039] The Mg measured by a Vickers hardness tester 92.5 Y5Au 2.5 The room temperature hardness of the as-cast alloy is 107.45 Hv.

[0040] Example 2

[0041] The difference from Example 1 is that pure Mg and Mg-Y master alloys with a purity greater than 99.99 wt.% and pure Au with a purity greater than 99.99 wt.% are used, according to Mg 98 The Y1Au1 (atomic fraction) alloy composition is smelted.

[0042] Mg was thus obtained. 98 The Y1Au1 as-cast alloy, the polished surface of which was observed by scanning electron microscopy as follows: Figure 5 As shown. This as-cast Mg 98 The Y1Au1 alloy includes a Mg matrix, a long-period stacked ordered phase, and Mg. 24 Y5 phase, a long-period stacked ordered phase composed of Mg 24 Y5 grows into the Mg matrix.

[0043] Example 3

[0044] The difference from Example 1 is that pure Mg and Mg-Y master alloys with a purity greater than 99.99 wt.% and pure Au with a purity greater than 99.99 wt.% are used, according to Mg 80 Y 10 Au 10 The alloy is smelted according to the (atomic fraction) alloy composition ratio.

[0045] Mg was thus obtained. 80 Y 10 Au 10 The as-cast alloy, the polished surface of which was observed by scanning electron microscopy as follows: Figure 6 As shown. This as-cast Mg 80 Y 10 Au 10 The alloy comprises a Mg matrix, a long-period stacked ordered phase, and Mg 24 Y5 phase, a long-period stacked ordered phase composed of Mg 24 Y5 grows into the Mg matrix.

[0046] Comparative Example 1

[0047] The difference from Example 1 is that pure Mg with a purity greater than 99.99 wt.% and Mg-Y master alloy were used, according to Mg 95 The Y5 (atomic fraction) alloy composition is smelted.

[0048] Mg was thus obtained. 95 Y5 as-cast alloy, the polished surface of which was observed by scanning electron microscopy as follows: Figure 7 As shown. This as-cast Mg 95 Y5 alloy contains only Mg matrix and Mg 24 Y5 phase, no long-period stacked ordered phase generation was found.

[0049] The Mg measured by a Vickers hardness tester95 The room temperature hardness of the Y5 as-cast alloy is 73.81 Hv.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A Mg-Y-Au alloy containing a long-period stacked ordered phase, characterized in that, The atomic percentage of each component in the Mg-Y-Au alloy is: Y 1~10 at.%, Au 1~10 at.%, with the balance being Mg; The Mg-Y-Au alloy contains a long-period stacked ordered phase with an 18R structure, whose stacking sequence is ABABABCACACABCBCBC, and the period length is 4.69 ± 0.5 nm. The Mg-Y-Au alloy comprises a Mg matrix, a long-period stacked ordered phase, and Mg. 24 Y5 phase, a long-period stacked ordered phase, mostly grows in the Mg matrix and Mg2+. 24 Between the Y5 phases, by Mg 24 Y5 grows into the Mg matrix; The preparation method of the Mg-Y-Au alloy containing a long-period stacked ordered phase includes the following steps: pure Mg, Mg-Y master alloy and pure Au are placed in a crucible in proportion and melted in a vacuum induction melting furnace. After the raw materials are completely melted, heating is stopped, the mixture is left to stand in the melting furnace and a protective gas is introduced. After the melt is completely solidified, it is cooled to room temperature. During smelting, the raw materials are heated to completely melt and accompanied by electromagnetic stirring; The melting temperature is 700℃ and the melting time is 1 minute.

2. The Mg-Y-Au alloy containing a long-period stacked ordered phase as described in claim 1, characterized in that, The atomic percentages of each component in the Mg-Y-Au alloy are: Y 5 at.%, Au 2.5 at.%, with the balance being Mg.

3. The Mg-Y-Au alloy containing a long-period stacked ordered phase as described in claim 1, characterized in that, The atomic percentage of each component in the Mg-Y-Au alloy is: Y 1 at.%, Au 1 at.%, with the balance being Mg.

4. The Mg-Y-Au alloy containing a long-period stacked ordered phase as described in claim 1, characterized in that, The atomic percentage of each component in the Mg-Y-Au alloy is: Y 10 at.%, Au 10 at.%, with the balance being Mg.

5. The method for preparing the Mg-Y-Au alloy containing a long-period stacked ordered phase according to any one of claims 1-4, characterized in that, Includes the following steps: Pure Mg, Mg-Y master alloy and pure Au were placed in a crucible in proportion and melted in a vacuum induction melting furnace. After the raw materials were completely melted, heating was stopped, and the mixture was left to stand in the melting furnace while a protective gas was introduced. After the melt was completely solidified, it was cooled to room temperature. Before melting in a vacuum induction melting furnace, a vacuum system is used to evacuate the furnace to a vacuum state. During smelting, the raw materials are heated to completely melt and accompanied by electromagnetic stirring; The melting temperature is 700℃ and the melting time is 1 minute.

6. The method for preparing the Mg-Y-Au alloy containing a long-period stacked ordered phase as described in claim 5, characterized in that, The protective gas is argon.

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