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CN-121976102-A - High heat-resistant magnesium alloy material and preparation method thereof

CN121976102ACN 121976102 ACN121976102 ACN 121976102ACN-121976102-A

Abstract

The invention discloses a high heat-resistant magnesium alloy material and a preparation method thereof, wherein the high heat-resistant magnesium alloy material comprises 13% -33% of rare earth elements, 0.2% -1.0% of Zr elements, less than or equal to 0.1% of impurity elements and the balance of Mg elements, the rare earth elements comprise two or more of Gd, tb, dy, er, lu, tm elements and contain Zr elements, and the impurity elements comprise Al, cu, fe, ni, si elements. The preparation method of ：Gd 3.0～20%,Tb 3.0～20%,Dy 3.0～25%,Er 3.0～28%,Lu 3.0～30%,Tm 3.0～25%.Zr 0.2～1.0%;Al≤0.02%,Cu≤0.05%,Fe≤0.05%,Ni≤0.02%,Si≤0.05%. mass percent of each element comprises alloy casting and heat treatment. The room temperature tensile strength of the high heat-resistant magnesium alloy prepared by the method exceeds 370 MPa after heat treatment, the elongation after breaking is not lower than 3.0%, the strength of the alloy is equivalent to the room temperature strength under the condition of 250 ℃ and the elongation after breaking is slightly increased, and the high strength is still maintained under the condition of 250-350 ℃.

Inventors

  • TANG CHANGPING
  • JIN YAOGUANG
  • DONG YU
  • LIU WENHUI

Assignees

  • 湖南科技大学

Dates

Publication Date
20260505
Application Date
20260309

Claims (10)

  1. 1. The high heat-resistant magnesium alloy material comprises the following elements in percentage by mass: 13% -33% of rare earth elements; Zr element 0.2-1.0%; Impurity element less than or equal to 0.1 percent, and The balance of Mg element, wherein: the rare earth elements include two or more of Gd, tb, dy, er, lu, tm elements; the impurity element includes Al, cu, fe, ni, si element.
  2. 2. The high heat resistant magnesium alloy material according to claim 1, wherein: The mass percentage of each element in the rare earth elements is as follows: Gd 3.0~20%,Tb 3.0~20%,Dy 3.0~25%,Er 3.0~28%,Lu 3.0~30%,Tm 3.0~25%。
  3. 3. The high heat resistant magnesium alloy material according to claim 1, wherein: The impurity elements comprise the following elements in percentage by mass: Al≤0.02%,Cu≤0.05%,Fe≤0.05%,Ni≤0.02%,Si≤0.05%。
  4. 4. a method for preparing the high heat resistant magnesium alloy material according to any one of claims 1 to 3, comprising the steps of: (1) Alloy casting, namely preheating, drying, high-temperature smelting, refining and pouring raw materials into a steel mould to obtain an ingot; (2) And (3) alloy heat treatment, namely performing heat treatment on the cast ingot in two steps, including solution heat treatment and aging heat treatment, and obtaining the high heat-resistant magnesium alloy material after the solution heat treatment and the aging heat treatment are finished.
  5. 5. The method of manufacturing according to claim 4, wherein: The preheating temperature in the step (1) is 100-200 ℃; The high-temperature smelting temperature is 740-760 ℃, the refining temperature is 780-800 ℃, and the casting temperature is 720-750 ℃; and preheating the steel die to 150-200 ℃ before casting treatment.
  6. 6. The method of manufacturing according to claim 4, wherein: The solution heat treatment of step (2) includes: Placing the cast ingot in a resistance heating furnace, heating to the first-stage temperature of 400-440 ℃, preserving heat for 2-24 h, performing pre-precipitation treatment, heating to the second-stage temperature of 500-580 ℃, preserving heat for 0.5-24 h, and then performing water quenching to obtain the solid solution treated cast ingot.
  7. 7. The method of manufacturing according to claim 4, wherein: The aging treatment in the step (2) comprises the following steps: And slowly heating the ingot subjected to solution treatment to 180-250 ℃ from room temperature, and preserving heat for 0.5-120 h to perform aging treatment to obtain the high heat-resistant magnesium alloy material.
  8. 8. The method of manufacturing according to claim 6, wherein: the temperature rising rate of the pre-precipitation treatment after the temperature rising to the first stage temperature is 5-20K/min, and the temperature rising rate of the pre-precipitation treatment after the temperature rising to the second stage temperature is more than 2K/min.
  9. 9. The method of manufacturing according to claim 7, wherein: The temperature rising rate is 0.5-2K/min.
  10. 10. A high heat-resistant magnesium alloy material produced by the production method according to any one of claims 4 to 9.

Description

High heat-resistant magnesium alloy material and preparation method thereof Technical Field The invention relates to a novel nonferrous metal material design, in particular to a high heat-resistant magnesium alloy material and a preparation method thereof. Background The magnesium alloy has wide application prospect in the fields of aerospace, weaponry and the like by virtue of excellent specific strength and lightweight characteristics, and is an important candidate material for lightweight manufacturing of high-performance parts. However, the low strength of pure magnesium makes it difficult to use directly in the manufacture of structural members. Research shows that the rare earth is used as alloying element to raise the room temperature and high temperature mechanical performance of alloy obviously. For example, the company Magnesium Elektron in the united kingdom developed WE54 and WE43 alloys containing Y and Nd elements, the WE54 alloy having a higher content of alloy elements, which had a room temperature tensile strength of 280MPa, a yield strength of 205MPa, an elongation after break of 4.0%, a 100 ℃ tensile strength of 260MPa, a yield strength of 197MPa, an elongation after break of 4.5%, a 150 ℃ tensile strength of 255MPa, a yield strength of 195MPa, an elongation after break of 5.0%, a 200 ℃ tensile strength of 241MPa, a yield strength of 183MPa, an elongation after break of 6.5%, a tensile strength at 250 ℃ of 230MPa, a yield strength of 175MPa, and an elongation after break of 9.0%. The ZM6 alloy containing rare earth is also developed in China, and is widely applied in engineering, wherein the room temperature tensile strength is 230MPa, the yield strength is 135MPa, the elongation after break is 3%, the 100 ℃ tensile strength is 203MPa, the yield strength is 130MPa, the elongation after break is 10.9%, the 150 ℃ tensile strength is 196MPa, the yield strength is 129MPa, the elongation after break is 9.4%, the 200 ℃ tensile strength is 193MPa, the yield strength is 126MPa, the elongation after break is 16.7%, the 250 ℃ tensile strength is 162MPa, the yield strength is 121MPa, the elongation after break is 13.3%, the 300 ℃ tensile strength is 109MPa, the yield strength is 79MPa, and the elongation after break is 22.2%. The room temperature strength of the Mg-Gd-Y series alloy developed in recent years can reach 400MPa, but the tensile strength is generally lower than 300MPa under the condition of 300 ℃. Therefore, the high-temperature performance of the existing magnesium alloy material has obvious short plates, and the high-temperature performance is reduced mainly because coarsening dissolution of the second phase and aggravation of grain boundary movement are easy to occur at high temperature. With the rise of the speed and acceleration of the new generation of aircrafts, higher requirements are put on the room temperature and high temperature performances of the materials. To meet this demand, development of a magnesium alloy material having high strength and high heat resistance is urgently required. Disclosure of Invention Aiming at the defects that the existing alloy is low in residual solid solubility and easy to dissolve back in a strengthening phase at high temperature, the invention provides a design method of a high heat-resistant magnesium alloy material, which aims at solving the problems that the strength of the existing alloy is obviously reduced at high temperature, aiming at the defects that the magnesium alloy designed by traditional components is insufficient in residual solid solubility at high temperature, the high heat-resistant magnesium alloy material is easy to dissolve back in the strengthening phase, and the heat resistance of the alloy is improved by taking elements with high solid solubility (the maximum solid solubility is more than 20% by mass) and high residual solid solubility (the residual solid solubility is more than 5% by mass at 350 ℃) as main alloy elements. The invention is realized by the following technical scheme: The invention firstly discloses a high heat-resistant magnesium alloy material which comprises the following elements in percentage by mass: 13% -33% of rare earth elements; Zr element 0.2-1.0%; Impurity element less than or equal to 0.1 percent, and The balance of Mg element, wherein: the rare earth elements include two or more of Gd, tb, dy, er, lu, tm elements; the impurity element includes Al, cu, fe, ni, si element. Further, the mass percentage of each element in the rare earth elements is as follows: Gd 3.0~20%,Tb 3.0~20%,Dy 3.0~25%,Er 3.0~28%,Lu 3.0~30%,Tm 3.0~25%。 Further, the impurity elements comprise the following elements in percentage by mass: Al≤0.02%,Cu≤0.05%,Fe≤0.05%,Ni≤0.02%,Si≤0.05%。 The invention also discloses a preparation method of the high heat-resistant magnesium alloy material according to any one of the above, which comprises the following steps: (1) Alloy casting, namely adding Mg element in the form of pure magn