Creep-resistant magnesium alloy with high elasticity modulus and high damping and preparation method thereof

Abstract

The invention discloses a creep-resistant magnesium alloy with high elasticity modulus and high damping and a preparation method thereof, and the creep-resistant magnesium alloy with high elasticity modulus and high damping comprises the following components in percentage by mass: 1.2%-3.5% of Zn element, 2.5%-12% of Gd element, 0.5%-6% of Yb element, 0.15%-1.2% of Ni element, 0.3%-0.8% of Mn element, 0-0.5% of Cu element, 0.1%-5% of HRE element and the balance of Mg element. The HRE element is one or more of a Dy element, a Sm element and a Tb element, and the mixing enthalpy delta H of the creep-resistant magnesium alloy with the high elastic modulus and the high damping is-1.1 kJ / mol to-0.2 kJ / mol. The creep-resistant magnesium alloy with high elastic modulus and high damping is suitable for the fields of aerospace, precise instruments, transportation, 3C electronics and the like, and has remarkable technical and economic values.

Description

Technical Field

[0001] This invention belongs to the field of metallic materials science and engineering, specifically relating to a creep-resistant, high elastic modulus, and high damping magnesium alloy and its preparation method. Background Technology

[0002] Magnesium alloys, due to their low density (about 1 / 4 that of steel and 2 / 3 that of aluminum), high specific strength and specific stiffness, good damping and electromagnetic shielding performance, and relatively abundant resources, have shown significant lightweighting potential in aerospace, transportation, electronic structural components, and precision equipment, and are regarded as important candidate materials for energy conservation, emission reduction and structural integration. At present, it is relatively easy to improve the single performance of magnesium alloys (such as strength or formability), but there is still a lack of systematic design path for the simultaneous improvement of the three aspects of "high temperature creep resistance, room temperature elastic modulus and damping performance". After years of development, compared with mature systems such as aluminum alloys, magnesium alloys are still at a disadvantage in terms of high temperature stability and multi-performance synergy, and large-scale application is constrained by a series of technical bottlenecks: (1) The performance is highly sensitive to temperature. Traditional Mg-Al system (AZ / AM) has poor thermal stability above 120-150℃ and is prone to coarsening / softening. Grades such as WE43 and ZM6 often have creep rates of 10 at 250℃ / 100 MPa. -6 -10 -7 s -1 (1) The range is insufficient to meet the requirements for higher service temperatures and low-speed creep; (2) The improvement of elastic modulus and damping is limited. The room temperature Young's modulus of commercial AZ-series and WE-series magnesium alloys is concentrated in 40-46 GPa, and the damping Q is limited. -1 (Strain amplitude approximately 0.1%) is typically <0.020, and even after optimization with elements such as Ca / Gd or hot deformation, the improvement in Young's modulus remains limited. Furthermore, high modulus is often accompanied by a decrease in damping performance (Q). -1 ≈0.010–0.013); (3) The mutual exclusion / dependency rules are not systematic. Microalloying elements (Mn, Bi, Ca, Ag, Cu, etc.) can be finely adjusted for creep, modulus and damping, but non-target coarse precipitation or microstructure instability is likely to occur; (4) The process path and composition are weakly coupled, and the direction of microstructure and performance evolution cannot be locked in the design stage. Therefore, it is necessary to find a magnesium alloy with excellent high-temperature creep resistance, high elastic modulus and excellent damping performance, so that it can be used in aerospace, precision instruments, transportation, 3C electronics and other fields. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a creep-resistant, high elastic modulus, and high damping magnesium alloy and its preparation method.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution.

[0005] A creep-resistant, high-elastic-modulus, high-damping magnesium alloy, by mass percentage, comprises the following components: 1.2%–3.5% Zn, 2.5%–12% Gd, 0.5%–6% Yb, 0.15%–1.2% Ni, 0.3%–0.8% Mn, 0–0.5% Cu, 0.1%–5% HRE, with the balance being Mg; wherein the HRE is one or more of Dy, Sm, and Tb; the enthalpy of mixing ΔH of the creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -1.1 kJ / mol to -0.2 kJ / mol; and the content of each element in the creep-resistant, high-elastic-modulus, high-damping magnesium alloy simultaneously satisfies conditions a), b), c), d), and e). a) ΣTM / ΣRE = 0.2~0.32, where ΣTM is the total content of Zn, Ni and Cu elements, and ΣRE is the total content of Gd, Yb and HRE elements; b) The total content of Gd, Yb and HRE elements is ≥6%; c) The content of Gd element is ≥30%ΣRE; d) The content of Yb element is ≥20%ΣRE; e) The content of Zn element is ≥60%ΣTM.

[0006] The above-mentioned creep-resistant, high elastic modulus, and high damping magnesium alloy is further improved in that the mixing enthalpy ΔH of the creep-resistant, high elastic modulus, and high damping magnesium alloy is -1.05 kJ / mol to -0.6 kJ / mol.

[0007] The above-mentioned creep-resistant, high elastic modulus, and high damping magnesium alloy is further improved in that the mixing enthalpy ΔH of the creep-resistant, high elastic modulus, and high damping magnesium alloy is -0.55 kJ / mol to -0.25 kJ / mol.

[0008] The above-mentioned creep-resistant, high elastic modulus, and high damping magnesium alloy is further improved by comprising one or more of Ag and Ca elements, wherein the content of Ag element is 0.03% to 0.12%, and the content of Ca element is 0.18% < 0.5%.

[0009] The above-mentioned creep-resistant, high elastic modulus, high damping magnesium alloy is further improved by comprising one or more of Ag, Ca, and Bi elements, wherein the content of Ag element is 0.03% to 0.12%, the content of Ca element is ≤0.18%, and the content of Bi element is 0.015% to 0.3%.

[0010] The above-mentioned creep-resistant, high elastic modulus, and high damping magnesium alloy is further improved in that when the HRE element is multiple of Dy, Sm, and Tb elements, the total HRE element content is ≤6%.

[0011] As a general technical concept, the present invention also provides a method for preparing the above-mentioned creep-resistant, high-elastic modulus, high-damping magnesium alloy, wherein when the mixing enthalpy of the creep-resistant, high-elastic modulus, high-damping magnesium alloy is -1.1 kJ / mol ≤ ΔH < -0.55 kJ / mol, the method includes the following steps: S1-1. Weigh the required raw materials according to the mass percentage of each component in the magnesium alloy, and then melt and cast them to obtain ingots. S2-1. Perform graded heat treatment on the ingot; the graded heat treatment is as follows: hold at 300℃~330℃ for 2h~10h, then hold at 450℃~470℃ for 0.5h~1h, and then hold at 500℃~530℃ for 0.5h~24h. S3-1. The material after graded heat treatment is extruded and deformed to obtain a creep-resistant, high elastic modulus, and high damping magnesium alloy; the extrusion and deformation temperature is 470℃~520℃, the extrusion speed is 0.1mm / s~2.0mm / s, and the cooling rate is 0.01℃ / s~1℃ / s.

[0012] As a general technical concept, the present invention also provides a method for preparing the above-mentioned creep-resistant, high-elastic modulus, high-damping magnesium alloy, wherein when the mixing enthalpy of the creep-resistant, high-elastic modulus, high-damping magnesium alloy is -0.55 kJ / mol ≤ ΔH < -0.35 kJ / mol, the method includes the following steps: S1-2. Weigh the required raw materials according to the mass percentage of each component in the magnesium alloy, and then melt and cast them to obtain ingots. S2-2. Perform graded heat treatment on the ingot; the graded heat treatment is as follows: hold at 300℃~330℃ for 2h~10h, then hold at 450℃~470℃ for 0.5h~1h, and then hold at 500℃~530℃ for 0.5h~24h. S3-2. The material after graded heat treatment is extruded and deformed to obtain a creep-resistant, high elastic modulus, and high damping magnesium alloy; the extrusion and deformation temperature is 350℃~420℃, the extrusion speed is 0.01mm / s~10mm / s, and the cooling rate is 0.01℃ / s~1℃ / s.

[0013] As a general technical concept, the present invention also provides a method for preparing the above-mentioned creep-resistant, high-elasticity modulus, high-damping magnesium alloy, wherein the method comprises the following steps when the mixing enthalpy of the creep-resistant, high-elasticity modulus, high-damping magnesium alloy is -0.35 kJ / mol ≤ ΔH ≤ -0.2 kJ / mol: S1-3. Weigh the required raw materials according to the mass percentage of each component in the magnesium alloy, and then melt and cast them to obtain ingots. S2-3. Perform graded heat treatment on the ingot; the graded heat treatment is as follows: hold at 470℃~480℃ for 1.5h~3h, and then hold at 500℃~530℃ for 0.5h~1.5h. S3-3. The material after graded heat treatment is extruded and deformed to obtain a high-elasticity, high-damping magnesium alloy with creep resistance; the extrusion and deformation temperature is 350℃~420℃, the extrusion speed is 0.01mm / s~10mm / s, and the cooling rate is 0.01℃ / s~1℃ / s.

[0014] In the creep-resistant, high-elastic modulus, and high-damping magnesium alloy of the present invention, the enthalpy of mixing ΔH is calculated by the Miedema method, the DFT method, or the CALPHAD method, or by weighting the calculation according to the atomic fraction (i.e., the mass percentage of each component) of the magnesium alloy.

[0015] Compared with the prior art, the advantages of the present invention are as follows: (1) This invention proposes a high-elasticity, high-damping magnesium alloy with high creep resistance. By controlling the content of Zn, Ni, Cu, Mn, Gd, Yb, and HRE elements, the magnesium alloy can be ensured to have both high elastic modulus and excellent creep resistance. By limiting ΣTM / ΣRE to 0.20-0.32, the reduction of high-damping LPSO phase and the precipitation of non-target phases (i.e., low-damping brittle phases) can be avoided, thus preventing a significant decrease in the damping performance of the magnesium alloy. By limiting the content of Gd element to ≥30% ΣRE and the content of Zn element to ≥60% ΣTM, the LPSO content can be guaranteed. The thermal stability of the SO phase enhances the creep resistance of magnesium alloys. By limiting the Yb content to ≥20% ΣRE, the LPSO phase can be softened, thereby improving the damping properties of the magnesium alloy. By limiting the mixing enthalpy ΔH of the magnesium alloy to -1.1 kJ / mol to -0.2 kJ / mol, the overall thermal stability of the magnesium alloy can be moderate, giving it high creep resistance, high modulus, and high damping characteristics. If the mixing enthalpy is too low, the alloy system will be too stable and hard, making internal friction difficult and unable to achieve high damping. If the mixing enthalpy is too high, the alloy system cannot achieve high creep resistance and high Young's modulus. The creep-resistant, high elastic modulus, and high damping magnesium alloy of this invention is suitable for aerospace, precision instruments, transportation, 3C electronics, and other fields, such as high-modulus lightweight structures, thermally stable and damping support components, vibration reduction and noise reduction components, and high-rigidity thin-walled shells, and has significant technical and economic value.

[0016] (2) The creep-resistant, high elastic modulus, and high damping magnesium alloy of the present invention also contains one or more of Ag, Ca, and Bi elements, which can finely adjust the creep / damping balance while maintaining the main performance. Specifically, Ag, Ca, and Bi elements all have the effect of reducing the mixing enthalpy and improving the thermal stability of the magnesium alloy. Ca and Ag elements have the effect of refining the Zn-containing precipitates, which can ensure the high damping of the magnesium alloy while taking into account its creep resistance and elastic modulus improvement. In addition, when Bi element is added, the coexistence of Bi and Ni elements is more conducive to the formation of LPSO phase and the occurrence of eutectic segregation phenomenon, further improving the damping performance of the magnesium alloy.

[0017] (3) The present invention also provides a method for preparing a high-toughness soluble magnesium alloy. The "graded heat treatment + extrusion deformation process" is directly related to the mixing enthalpy ΔH. The graded heat treatment can avoid overheating of the heat-sensitive phase in the as-cast structure, sufficient dissolution of the eutectic phase, and sufficient dynamic precipitation during the final extrusion and cooling process. At the same time, the alloy with a large absolute value of mixing enthalpy adopts a more complex graded process. This is because the alloy itself has a higher volume fraction of heat-sensitive phase, and also to ensure that the harder brittle phase in the alloy can be fully dissolved, thus avoiding cracking during the subsequent preparation process. Detailed Implementation

[0018] The present invention will be further described below with reference to specific preferred embodiments, but this does not limit the scope of protection of the present invention. All materials and instruments used in the following embodiments are commercially available.

[0019] Example 1 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 1.2% Zn, 2.5% Gd, 2.0% Yb, 1.8% Dy, 0.25% Ni, 0.3% Mn, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.277 kJ / mol.

[0020] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 470℃ for 1.5h, and then hold at 500℃ for 0.5h. S3. The material after graded heat treatment is extruded and deformed at a temperature of 350℃, an extrusion speed of 0.01mm / s, and a cooling rate of 1℃ / s to obtain a creep-resistant, high-elastic-modulus, high-damping magnesium alloy.

[0021] Example 2 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 1.5% Zn, 2.8% Gd, 2.0% Yb, 2.0% Dy, 0.3% Ni, 0.3% Mn, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.320 kJ / mol.

[0022] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 480℃ for 3 hours, and then hold at 530℃ for 1.5 hours. S3. The material after graded heat treatment is extruded and deformed at a temperature of 380℃, an extrusion speed of 5.0mm / s, and a cooling rate of 1℃ / s to obtain a creep-resistant, high-elastic-modulus, high-damping magnesium alloy.

[0023] Example 3 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 1.2% Zn, 0.5% Cu, 3.2% Gd, 2.2% Yb, 1.8% Dy, 0.5% Sm, 0.15% Ni, and 0.3% Mn, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.370 kJ / mol.

[0024] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 300℃ for 5 hours, then hold at 450℃ for 1 hour, and then hold at 500℃ for 5 hours. S3. The material after graded heat treatment is extruded and deformed at a temperature of 385℃, an extrusion speed of 1.2mm / s, and a cooling rate of 1℃ / s to obtain a creep-resistant, high-elastic-modulus, high-damping magnesium alloy.

[0025] Example 4 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 2.0% Zn, 3.5% Gd, 2.5% Yb, 1.8% Dy, 0.4% Tb, 0.4% Ni, 0.3% Mn, and 0.1% Cu, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.424 kJ / mol.

[0026] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 300℃ for 10h, then hold at 460℃ for 0.5h, and then hold at 500℃ for 24h. S3. The material after graded heat treatment is extruded and deformed at a temperature of 380℃, an extrusion speed of 1.2mm / s, and a cooling rate of 1℃ / s to obtain a creep-resistant, high-elastic-modulus, high-damping magnesium alloy.

[0027] Example 5 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 2.2% Zn, 4.0% Gd, 2.8% Yb, 2.0% Dy, 0.4% Ni, 0.3% Mn, 0.26% Ca, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.499 kJ / mol.

[0028] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 310℃ for 2 hours, then hold at 460℃ for 1 hour, and then hold at 510℃ for 0.5 hours. S3. The material after graded heat treatment is extruded and deformed at a temperature of 415℃, an extrusion speed of 0.1mm / s, and a cooling rate of 0.5℃ / s to obtain a creep-resistant, high-elastic-modulus, high-damping magnesium alloy.

[0029] Example 6 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 2.1% Zn, 4.5% Gd, 3.0% Yb, 2.2% Dy, 0.4% Ni, 0.3% Mn, 0.03% Bi, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.495 kJ / mol.

[0030] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 310℃ for 10 hours, then hold at 460℃ for 1 hour, and then hold at 510℃ for 2 hours. S3. The material after graded heat treatment is extruded and deformed at a temperature of 380℃, an extrusion speed of 1.0 mm / s, and a cooling rate of 0.5℃ / s to obtain a creep-resistant, high-elastic-modulus, high-damping magnesium alloy.

[0031] Example 7 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 2.3% Zn, 5.0% Gd, 3.5% Yb, 2.0% Dy, 0.5% Ni, 0.4% Mn, 0.15% Cu, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.542 kJ / mol.

[0032] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 320℃ for 4 hours, then hold at 470℃ for 0.5 hours, and then hold at 510℃ for 24 hours. S3. The material after graded heat treatment is extruded and deformed at a temperature of 390℃, an extrusion speed of 1.3mm / s, and a cooling rate of 0.2℃ / s to obtain a creep-resistant, high-elastic modulus, and high-damping magnesium alloy.

[0033] Example 8 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 2.4% Zn, 5.5% Gd, 4.0% Yb, 1.2% Dy, 0.6% Sm, 0.5% Ni, 0.4% Mn, 0.08% Ag, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.587 kJ / mol.

[0034] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 320℃ for 10h, then hold at 470℃ for 0.8h, and then hold at 520℃ for 14h. S3. The material after graded heat treatment is extruded and deformed at a temperature of 470℃, an extrusion speed of 1.3mm / s, and a cooling rate of 0.2℃ / s to obtain a high-elasticity, high-damping magnesium alloy with creep resistance.

[0035] Example 9 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 2.6% Zn, 6.0% Gd, 4.5% Yb, 2.2% Dy, 0.55% Ni, 0.4% Mn, and 0.2% Cu, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.673 kJ / mol.

[0036] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 330℃ for 2 hours, then hold at 470℃ for 1 hour, and then hold at 520℃ for 24 hours. S3. The material after graded heat treatment is extruded and deformed at a temperature of 495℃, an extrusion speed of 0.1mm / s, and a cooling rate of 0.1℃ / s to obtain a creep-resistant, high-elastic modulus, and high-damping magnesium alloy.

[0037] Example 10 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 2.8% Zn, 7.5% Gd, 4.2% Yb, 2.5% Dy, 0.5% Tb, 0.6% Ni, 0.5% Mn, and 0.3% Cu, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.793 kJ / mol.

[0038] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 330℃ for 8 hours, then hold at 470℃ for 1 hour, and then hold at 530℃ for 4 hours. S3. The material after graded heat treatment is extruded and deformed at a temperature of 495℃, an extrusion speed of 1.5mm / s, and a cooling rate of 0.1℃ / s to obtain a creep-resistant, high-elastic modulus, and high-damping magnesium alloy.

[0039] Example 11 A creep-resistant, high-elastic-modulus, high-damping magnesium alloy of the present invention comprises, by mass percentage: 3.0% Zn, 1.2% Ni, 10.5% Gd, 4.0% Yb, 0.8% Dy, 0.8% Sm, 0.4% Mn, 0.3% Bi, 0.12% Ag, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this creep-resistant, high-elastic-modulus, high-damping magnesium alloy is -0.993 kJ / mol.

[0040] A method for preparing a creep-resistant, high-elastic-modulus, high-damping magnesium alloy according to this embodiment includes the following steps: S1. Weigh the required raw materials according to the mass percentage of each component in the above magnesium alloy, and then melt and cast them to obtain ingots. S2. Perform graded heat treatment on the ingot, that is, hold at 330℃ for 10 hours, then hold at 470℃ for 1 hour, and then hold at 530℃ for 24 hours. S3. The material after graded heat treatment is extruded and deformed at a temperature of 520℃, an extrusion speed of 0.1mm / s, and a cooling rate of 0.05℃ / s to obtain a high-elasticity, high-damping magnesium alloy with creep resistance.

[0041] Comparative Example 1 A magnesium alloy, by mass percentage, comprises the following components: 0.63% Zn, 2.5% Gd, 2.0% Yb, 1.6% Dy, 0.42% Ni, and 0.3% Mn, with the balance being Mg and unavoidable impurities. The alloy has a Zn content of 0.63%. The enthalpy of mixing ΔH of this magnesium alloy is -0.247 kJ / mol.

[0042] The preparation method of this magnesium alloy is basically the same as that of the preparation method of the creep-resistant, high elastic modulus, and high damping magnesium alloy in Example 1, the only difference being that the composition of the magnesium alloy is different.

[0043] Comparative Example 2 A magnesium alloy, by mass percentage, comprises the following components: 3.0% Zn, 7.0% Gd, 3.2% Yb, 1.5% Dy, 0.5% Tb, 1.2% Ni, 0.5% Mn, and 0.5% Cu, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this magnesium alloy is -0.744 kJ / mol.

[0044] The preparation method of this magnesium alloy is basically the same as that of the preparation method of the creep-resistant, high elastic modulus, and high damping magnesium alloy in Example 10, the only difference being that the composition of the magnesium alloy is different.

[0045] Comparative Example 3 A magnesium alloy, by mass percentage, comprises the following components: 1.2% Zn, 2.5% Gd, 2.0% Yb, 1.2% Dy, 0.25% Ni, and 0.3% Mn, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this magnesium alloy is -0.252 kJ / mol.

[0046] The preparation method of this magnesium alloy is basically the same as that of the preparation method of the creep-resistant, high elastic modulus, and high damping magnesium alloy in Example 1, the only difference being that the composition of the magnesium alloy is different.

[0047] Comparative Example 4 A magnesium alloy, by mass percentage, comprises the following components: 2.6% Zn, 2.5% Gd, 4.5% Yb, 4.7% Dy, 0.55% Ni, 0.4% Mn, and 0.2% Cu, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this comparative magnesium alloy is -0.608 kJ / mol.

[0048] The preparation method of this magnesium alloy is basically the same as that of the preparation method of the creep-resistant, high elastic modulus, and high damping magnesium alloy in Example 9, the only difference being that the composition of the magnesium alloy is different.

[0049] Comparative Example 5 A magnesium alloy, by mass percentage, comprises the following components: 2.6% Zn, 9.0% Gd, 1.5% Yb, 2.2% Dy, 0.55% Ni, 0.4% Mn, and 0.2% Cu, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this magnesium alloy is -0.707 kJ / mol.

[0050] The preparation method of this magnesium alloy is basically the same as that of the preparation method of the creep-resistant, high elastic modulus, and high damping magnesium alloy in Example 9, the only difference being that the composition of the magnesium alloy is different.

[0051] Comparative Example 6 A magnesium alloy, by mass percentage, comprises the following components: 1.2% Zn, 6.0% Gd, 4.5% Yb, 2.2% Dy, 1.2% Ni, 0.4% Mn, and 0.5% Cu, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this magnesium alloy is -0.648 kJ / mol.

[0052] The preparation method of this magnesium alloy is basically the same as that of the preparation method of the creep-resistant, high elastic modulus, and high damping magnesium alloy in Example 9, the only difference being that the composition of the magnesium alloy is different.

[0053] Comparative Example 7 A magnesium alloy, by mass percentage, comprises the following components: 3.5% Zn, 1.2% Ni, 11.5% Gd, 6.0% Yb, 1.8% Dy, 2.8% Sm, 0.4% Mn, 0.3% Bi, and 0.12% Ag, with the balance being Mg and unavoidable impurities. The enthalpy of mixing ΔH of this magnesium alloy is -1.393 kJ / mol.

[0054] The preparation method of this magnesium alloy is basically the same as that of the preparation method of the creep-resistant, high elastic modulus, and high damping magnesium alloy in Example 11, the only difference being that the composition of the magnesium alloy is different.

[0055] The creep resistance, high elastic modulus, and high damping magnesium alloys prepared in Examples 1 to 11, and the magnesium alloys prepared in Comparative Examples 1 to 7 were tested for creep performance at 250°C and 100 MPa, Young's modulus at room temperature, and damping performance at a strain amplitude of 0.001. The results are shown in Table 1.

[0056] Table 1 Performance test results of magnesium alloys

[0057] As shown in Table 1, the room-temperature Young's modulus of the creep-resistant, high-elasticity, high-damping magnesium alloys prepared in Examples 1 to 11 can reach 46.2 GPa to 57.5 GPa, which is 10% to 30% higher than that of conventional magnesium alloys (43 GPa to 45 GPa). In particular, when the enthalpy of mixing ΔH of the creep-resistant, high-elasticity, high-damping magnesium alloy is ≤ -0.6 kJ / mol, the room-temperature Young's modulus of the magnesium alloy can reach above 51.2 GPa. The Q of the creep-resistant, high-elasticity, high-damping magnesium alloys prepared in Examples 1 to 11... -1 In the range of 0.0215 to 0.0358, compared to conventional magnesium alloys (Q -1 <0.010), its damping performance can be improved by 50% to 200%. The creep-resistant, high-elastic modulus, high-damping magnesium alloys prepared in Examples 1 to 11 have a minimum creep rate of 1.5 × 10⁻⁶ under conditions of 250℃ / 100MPa. -9 ~9.3×10 -8 Within the range, compared to conventional AZ / AM series magnesium alloys (10 -5 ~9.3×10 -6 The minimum creep rate is reduced by 2 to 4 orders of magnitude. In contrast, the magnesium alloy prepared in Comparative Example 1, due to insufficient Zn content and unstable LPSO phase, exhibits a minimum creep rate as high as 5.6 × 10⁻⁶. -7 s -1 Its creep resistance is not ideal. In Comparative Example 2, the magnesium alloy with an excessively high ΣTM / ΣRE ratio leads to the formation of a large number of coarse and brittle phases, deteriorating its damping performance (Q). -1 The total content of Gd, Yb, and Dy in the magnesium alloy prepared in Comparative Example 3 was insufficient, resulting in inadequate solid solution strengthening. This alloy exhibited a minimum creep rate as high as 9.7 × 10⁻⁶. -7 s -1 The Young's modulus decreased to 43.2 GPa, indicating unsatisfactory creep resistance and elastic modulus. In the magnesium alloy prepared in Comparative Example 4, the excessively low Gd ratio affected the structural stability of the LPSO phase, increasing the minimum creep rate to 3.9 × 10⁻⁶. -7 s -1 Its creep resistance is not ideal. In the magnesium alloy prepared in Comparative Example 5, the insufficient Yb content makes LPSO too hard, which is detrimental to damping internal friction and leads to Q... -1 The minimum creep rate is 0.0179, indicating unsatisfactory damping performance. In the magnesium alloy prepared in Comparative Example 6, the excessively low Zn ratio inhibited the formation of the LPSO phase and promoted the precipitation of other harmful phases, resulting in a minimum creep rate of 1.3 × 10⁻⁶ for this magnesium alloy. -7 s -1 Q -1The coefficient of performance (Q) is 0.0156, indicating unsatisfactory creep resistance and damping performance. The magnesium alloy prepared in Comparative Example 7 exhibits an excessively negative mixing enthalpy and excessively high alloy stability, which is detrimental to damping internal friction, leading to a decrease in Q. -1 The value is 0.0102, indicating that its damping performance is not ideal.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the spirit and technical essence of the present invention. Therefore, any simple modifications, equivalent substitutions, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall still fall within the protection scope of the technical solutions of the present invention.

Claims

1. A creep resistant, high modulus, high damping magnesium alloy characterized in that, The anti-creep high-elasticity modulus high-damping magnesium alloy comprises the following components in percentage by mass: 1.2-3.5% of Zn element, 2.5-12% of Gd element, 0.5-6% of Yb element, 0.15-1.2% of Ni element, 0.3-0.8% of Mn element, 0-0.5% of Cu element, 0.1-5% of HRE element, and the balance of Mg element; the HRE element is one or more of Dy element, Sm element and Tb element; the mixing enthalpy ΔH of the anti-creep high-elasticity modulus high-damping magnesium alloy is -1.1 kJ / mol to -0.2 kJ / mol; the content of each element in the anti-creep high-elasticity modulus high-damping magnesium alloy satisfies the conditions of a), b), c), d) and e) simultaneously: a) ΣTM / ΣRE = 0.2-0.32, wherein ΣTM is the total content of Zn element, Ni element and Cu element, and ΣRE is the total content of Gd element, Yb element and HRE element; b) the total content of Gd element, Yb element and HRE element is ≥6%; c) the content of Gd element is ≥30%ΣRE; d) the content of Yb element is ≥20%ΣRE; e) the content of Zn element is ≥60%ΣTM.

2. The creep resistant, high elastic modulus, high damping magnesium alloy of claim 1, wherein, The mixing enthalpy ΔH of the anti-creep high-elasticity modulus high-damping magnesium alloy is -1.05 kJ / mol to -0.6 kJ / mol.

3. The creep resistant, high elastic modulus, high damping magnesium alloy of claim 1, wherein, The mixing enthalpy ΔH of the anti-creep high-elasticity modulus high-damping magnesium alloy is -0.55 kJ / mol to -0.25 kJ / mol.

4. The creep resistant, high elastic modulus, high damping magnesium alloy of any one of claims 1-3, wherein, The anti-creep high-elasticity modulus high-damping magnesium alloy further comprises one or more of Ag element and Ca element, the content of the Ag element is 0.03%-0.12%, and the content of the Ca element is ≤0.5%.

5. The creep resistant, high elastic modulus, high damping magnesium alloy of any one of claims 1-3, wherein, The anti-creep high-elasticity modulus high-damping magnesium alloy further comprises one or more of Ag element, Ca element and Bi element, the content of the Ag element is 0.03%-0.12%, the content of the Ca element is ≤0.18%, and the content of the Bi element is 0.015%-0.3%.

6. The creep resistant, high elastic modulus, high damping magnesium alloy of any one of claims 1-3, wherein, When the HRE element is multiple of Dy element, Sm element and Tb element, the total content of the HRE element is ≤6%.

7. A method of producing the creep-resistant, high-elastic-modulus, high-damping magnesium alloy as claimed in any one of claims 1 to 6, characterized in that, When the mixing enthalpy of the anti-creep high-elasticity modulus high-damping magnesium alloy is -1.1 kJ / mol≤ΔH<-0.55 kJ / mol, the following steps are included: S1-1, according to the mass percentage of each component in the magnesium alloy, the required raw materials are weighed, smelted and cast to obtain an ingot; S2-1, the ingot is subjected to a staged heat treatment; the staged heat treatment is: heat preservation at 300-330℃ for 2-10h, heat preservation at 450-470℃ for 0.5-1h, and then heat preservation at 500-530℃ for 0.5-24h; S3-1, the material after the staged heat treatment is subjected to extrusion deformation to obtain the anti-creep high-elasticity modulus high-damping magnesium alloy; the extrusion deformation is performed at a temperature of 470-520℃, an extrusion speed of 0.1-2.0mm / s and a cooling speed of 0.01-1℃ / s.

8. A method of producing the creep resistant, high modulus, high damping magnesium alloy according to any one of claims 1 to 6, characterized in that, When the mixing enthalpy of the anti-creep high-elastic modulus high-damping magnesium alloy is -0.55kJ / mol≤ΔH<-0.35kJ / mol, the method comprises the following steps: S1-2, according to the mass percentage of each component in the magnesium alloy, the required raw materials are weighed, smelting and casting are carried out, and an ingot is obtained; S2-2, the ingot is subjected to a staged heat treatment; the staged heat treatment is: heat preservation at 300-330℃ for 2-10h, heat preservation at 450-470℃ for 0.5-1h, and then heat preservation at 500-530℃ for 0.5-24h; S3-2, the material after the staged heat treatment is subjected to extrusion deformation to obtain the anti-creep high-elastic modulus high-damping magnesium alloy; the extrusion deformation temperature is 350-420℃, the extrusion speed is 0.01-10mm / s, and the cooling speed is 0.01-1℃ / s.

9. A method of producing the creep resistant, high modulus, high damping magnesium alloy according to any one of claims 1 to 6, characterized in that, When the mixing enthalpy of the anti-creep high-elastic modulus high-damping magnesium alloy is -0.35kJ / mol≤ΔH≤-0.2kJ / mol, the method comprises the following steps: S1-3, according to the mass percentage of each component in the magnesium alloy, the required raw materials are weighed, smelting and casting are carried out, and an ingot is obtained; S2-3, the ingot is subjected to a staged heat treatment; the staged heat treatment is: heat preservation at 470-480℃ for 1.5-3h, and heat preservation at 500-530℃ for 0.5-1.5h; S3-3, the material after the staged heat treatment is subjected to extrusion deformation to obtain the anti-creep high-elastic modulus high-damping magnesium alloy; the extrusion deformation temperature is 350-420℃, the extrusion speed is 0.01-10mm / s, and the cooling speed is 0.01-1℃ / s.

Images