CN110616356B - Er-containing magnesium alloy and preparation method thereof - Google Patents

Er-containing magnesium alloy and preparation method thereof Download PDF

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CN110616356B
CN110616356B CN201910977555.4A CN201910977555A CN110616356B CN 110616356 B CN110616356 B CN 110616356B CN 201910977555 A CN201910977555 A CN 201910977555A CN 110616356 B CN110616356 B CN 110616356B
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alloy
magnesium
magnesium alloy
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containing magnesium
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CN110616356A (en
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崔烨
张中武
范明雨
韩佳澍
陈丹
张洋
孙利昕
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Harbin Engineering University
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/02—Making non-ferrous alloys by melting
    • C22C1/03—Making non-ferrous alloys by melting using master alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C23/00—Alloys based on magnesium
    • C22C23/04—Alloys based on magnesium with zinc or cadmium as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C23/00—Alloys based on magnesium
    • C22C23/06—Alloys based on magnesium with a rare earth metal as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/002—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working by rapid cooling or quenching; cooling agents used therefor
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/06—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of magnesium or alloys based thereon

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Abstract

The invention provides an Er-containing magnesium alloy and a preparation method thereof, wherein the Er-containing magnesium alloy comprises the following components in atomic percentage: 0.2 to 2.0 percent of Er, 0.2 to 2.0 percent of Y, 0.2 to 2.0 percent of Zn, and the balance of Mg and inevitable impurities; the method comprises the following steps: smelting, homogenizing, deforming and aging. The addition of Er atoms can adjust the content and distribution of long-period ordered structural phases in the magnesium alloy, and the precipitated phases can prevent basal plane dislocation slippage and improve the strength of the alloy; the LPSO phase and the magnesium matrix phase are in a coherent relationship, which can hinder crack initiation and improve the plasticity of the alloy; er and magnesium have similar atomic radius, and the addition of Er in the Mg matrix can achieve good solid solution strengthening effect; the addition of Er can also effectively adjust W phase and distribution thereof in the alloy, and the second phases have the function of hindering dislocation slip, so that the addition of Er can effectively regulate and control the mechanical property of the alloy.

Description

Er-containing magnesium alloy and preparation method thereof
Technical Field
The invention relates to an alloy and a preparation method thereof, in particular to an Er-containing magnesium alloy and a preparation method thereof, belonging to the technical field of metal materials.
Background
The magnesium alloy is used as the lightest engineering metal material at present, has a series of unique advantages of high specific strength and specific rigidity, good damping vibration attenuation, strong electromagnetic shielding and heat conducting performance, easy cutting and processing, easy recovery and the like, and has wide application background in modern industries such as aerospace, automobiles, computers, communication, consumer electronics and the like. However, magnesium alloys often have severe limitations in their wide application in production and life due to low strength, poor plasticity, and the like. Therefore, improving the plasticity and strength of magnesium alloys is an important direction in the development of magnesium alloy materials.
In general, an increase in strength of an alloy is accompanied by a decrease in plasticity, and thus it is difficult to obtain a cast magnesium alloy having both high strength and high plasticity. This is due to the presence of second phase particles which exacerbate dislocation stacking and improve alloy strength, but also promote crack initiation and reduce alloy plasticity. The industrial application of the alloy is greatly limited. The development of high-plasticity and high-strength cast magnesium alloy becomes the key point of magnesium alloy research work.
Disclosure of Invention
The invention aims to provide an Er-containing magnesium alloy and a preparation method thereof for developing a cast magnesium alloy with high plasticity and high strength.
The purpose of the invention is realized as follows:
an Er-containing magnesium alloy comprises the following components in atomic percentage: er 0.2-2.0%, Y0.2-2.0%, Zn 0.2-2.0%, and Mg and inevitable impurities in balance.
A process for preparing Er-contained Mg alloy includes such steps as smelting Er (0.2-2.0 wt.%), Y (0.2-2.0), Zn (0.2-2.0), and Mg and inevitable impurities (rest), and casting.
The invention also includes such features:
homogenizing the alloy ingot or casting, and homogenizing and annealing at the temperature of 300-550 ℃ for 0.5-20 h;
deforming the homogenized alloy ingot or casting at 250-400 deg.c for several times in total deformation rate of 20-90%, and quenching to cool fast;
and (3) carrying out aging treatment after deformation: the temperature is 150-300 ℃, and the aging time is 0.1-200 h;
the method comprises the following steps: smelting, homogenizing, deforming and aging.
Compared with the prior art, the invention has the beneficial effects that:
the rare earth element Er is added on the basis of the Mg-Y-Zn alloy, so that the room-temperature mechanical property of the alloy is obviously improved, and the reasons are mainly the following: firstly, the content of a long-period ordered structure phase and the distribution of the long-period ordered structure phase in the magnesium alloy can be adjusted by adding Er atoms, and the precipitated phase can prevent basal plane dislocation slippage and improve the strength of the alloy; secondly, the LPSO phase and the magnesium matrix phase are in a coherent relationship, which can hinder crack initiation and improve the plasticity of the alloy; thirdly, Er has a similar atomic radius with magnesium, and the addition of Er in the Mg matrix can achieve a good solid solution strengthening effect; in addition, the addition of Er can also effectively adjust W phase and distribution thereof in the alloy, and the second phases have the effect of hindering dislocation glide, so that the addition of Er can effectively regulate and control the mechanical property of the alloy. Finally, the Er element is added and the mechanical property of the Mg-rare earth-Zn alloy can be further improved through corresponding heat treatment, so that the alloy with high strength and high plasticity can be obtained at the same time.
Drawings
FIG. 1 is a Mg97.5Y1Zn1Er0.5 as-cast tensile stress-strain curve;
FIG. 2 is a as-cast microstructure of Mg97.5Y1Zn1Er0.5;
FIG. 3 is the as-cast microstructure of Mg97Y1Zn1Er 1;
FIG. 4 shows the microstructure of Mg97.5Y1Zn1Er0.5 cast at 520 ℃ for 10h after water cooling.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
The rare earth element Er has larger solid solubility in magnesium, and the addition of a proper amount of rare earth element Er in the magnesium alloy can play a good role in solid solution strengthening; the addition of the rare earth can also effectively improve the alloy structure and the microstructure thereof, improve the room temperature and high temperature mechanical properties of the alloy and enhance the corrosion resistance of the magnesium alloy; meanwhile, stable dispersed phase particles can be separated out in the magnesium alloy by adding the rare earth element, and the precipitation strengthening effect is good. In addition, in 2001, scientists prepared Mg-Y-Zn alloy with long-period stacking structure phase (LPSO) in a laboratory, the alloy shows extremely high room temperature mechanical properties, and then a large number of scholars carry out detailed research on the long-period stacking structure phase, so that the long-period stacking structure phase can increase the strength of the alloy without sacrificing plasticity, and a new idea is provided for alloy development. The rare earth element Er meets the standard condition for forming LPSO phase, and the experiment proves that the rare earth element Mg-Er-Zn alloy has LPSO phase. The method comprehensively considers the factors, adds the rare earth element Er into the magnesium alloy, and further controls the solid solubility of the Er element in the Mg matrix on the basis of regulating and controlling the LPSO phase structure and the volume fraction, thereby achieving the purpose of simultaneously improving the strength and the plasticity of the alloy.
At present, the application of rare earth element Er in magnesium alloy is rarely researched. It is not reported that Er element is used for regulating and controlling matrix phase components in magnesium alloy and simultaneously regulating and controlling LPSO phase structure. For example, the patent 201811550142.X and the like research the influence of rare earth elements including Er on the mechanical property of the magnesium alloy, but the regulation of Er on the matrix phase composition and LPSO phase of the magnesium alloy is not involved, the invention provides the effect that the Er element is added into the magnesium alloy to replace part of Y element in Mg-Y-Zn alloy, the content of solid solution atoms in the matrix phase of the alloy is effectively regulated, the LPSO phase composition is regulated, the high plasticity is ensured, and the alloy strength is improved.
The invention aims to provide a high-plasticity cast magnesium alloy and a preparation method thereof under the condition of ensuring the strength of the magnesium alloy, aiming at the defects of the prior art. The chemical components are as follows (atom percentage): er 0.2-2.0%, Y0.2-2.0%, Zn 0.2-2.0%, and Mg and inevitable impurities in balance.
The preparation method of the Er-containing magnesium alloy comprises the following steps of: a. smelting, b, homogenizing, c, deforming and d, aging.
a. Smelting: according to the atomic percentage, the alloy is smelted under the condition of vacuum or protective atmosphere, and then an alloy ingot is cast or a casting is directly cast.
b. Homogenizing: the alloy ingot is subjected to homogenizing annealing at the temperature of 300-550 ℃ for 0.5-20 h.
c. Deformation: the deformation temperature range is 250-400 ℃, the total deformation rate is 20-90%, and the steel can be deformed for many times and then quenched and rapidly cooled.
d. Aging treatment: the temperature range is 150-300 ℃, and the aging time range is 0.1-200 h.
Example 1
The rare earth magnesium alloy in the embodiment comprises the following chemical components in atomic percentage: 0.5% Er, 1% Y, 1% Zn, and the balance Mg and unavoidable impurities. Adding pure magnesium ingot, heating the furnace to 720-740 ℃, and introducing SF6：CO2The volume ratio is 1: and (2) after the magnesium ingot is completely melted, skimming dross on the surface of the melt by 200 protective gas, sequentially adding Mg-20Y intermediate alloy and Mg-30Er intermediate alloy, raising the furnace temperature to 750 ℃, keeping the temperature for 15-20 min after the intermediate alloy is completely melted, pouring the intermediate alloy into a pre-preheated mold, and casting the intermediate alloy into an alloy ingot. The room temperature mechanical properties are tested as follows: the tensile strength was 234MPa, the yield strength was 152MPa, and the elongation was 13%.
Example 2
The rare earth magnesium alloy in the embodiment comprises the following chemical components in atomic percentage: 1% Er, 1% Y, 1% Zn, and the balance Mg and unavoidable impurities. Adding pure magnesium ingot, heating the furnace to 720-740 ℃, and introducing SF6：CO2The volume ratio is 1: and (2) after the magnesium ingot is completely melted, skimming dross on the surface of the melt by 200 protective gas, sequentially adding Mg-20Y intermediate alloy and Mg-30Er intermediate alloy, raising the furnace temperature to 750 ℃, keeping the temperature for 15-20 min after the intermediate alloy is completely melted, pouring the intermediate alloy into a pre-preheated mold, and casting the intermediate alloy into an alloy ingot. The room temperature mechanical properties are tested as follows: the tensile strength is 229MPa, the yield strength is 147MPa, and the elongation is 17%.
Example 3
The rare earth magnesium alloy in the embodiment comprises the following chemical components in atomic percentage: 0.5% Er, 1% Y, 1% Zn, and the balance Mg and unavoidable impurities. Adding pure magnesium ingot, heating the furnace to 720-740 ℃, and introducing SF6：CO2The volume ratio is 1: 200 of protective gas, skimming dross on the surface of the melt after the magnesium ingot is completely melted, and sequentially adding the skimming dross into Mg-20YAnd (3) heating the master alloy and the Mg-30Er master alloy to 750 ℃, keeping the temperature for 15-20 min after the master alloy is completely melted, and pouring the master alloy into a pre-preheated mold to cast an alloy ingot. The alloy is kept at 520 ℃ for 10 h. And then water-cooled. The rare earth magnesium alloy in the embodiment has room temperature mechanical properties of 229MPa of tensile strength, 145MPa of yield strength and 25% of elongation percentage.
Example 4
The rare earth magnesium alloy in the embodiment comprises the following chemical components in atomic percentage: 1% Er, 1% Y, 1% Zn, and the balance Mg and unavoidable impurities. Adding pure magnesium ingot, heating the furnace to 720-740 ℃, and introducing SF6：CO2The volume ratio is 1: and (2) after the magnesium ingot is completely melted, skimming dross on the surface of the melt by 200 protective gas, sequentially adding Mg-20Y intermediate alloy and Mg-30Er intermediate alloy, raising the furnace temperature to 750 ℃, keeping the temperature for 15-20 min after the intermediate alloy is completely melted, pouring the intermediate alloy into a pre-preheated mold, and casting the intermediate alloy into an alloy ingot. The alloy is kept at 520 ℃ for 10 h. And then water-cooled. The rare earth magnesium alloy in the embodiment has room temperature mechanical properties of tensile strength of 239MPa, yield strength of 155MPa and elongation of 27% through tests.
Example 5
The rare earth magnesium alloy in the embodiment comprises the following chemical components in atomic percentage: 1% Er, 1% Y, 1% Zn, and the balance Mg and unavoidable impurities. Adding pure magnesium ingot, heating the furnace to 720-740 ℃, and introducing SF6：CO2The volume ratio is 1: and (2) after the magnesium ingot is completely melted, skimming dross on the surface of the melt by 200 protective gas, sequentially adding Mg-20Y intermediate alloy and Mg-30Er intermediate alloy, raising the furnace temperature to 750 ℃, keeping the temperature for 15-20 min after the intermediate alloy is completely melted, pouring the intermediate alloy into a pre-preheated mold, and casting the intermediate alloy into an alloy ingot. The alloy is kept at 520 ℃ for 10 h. And then water-cooled. Then preheated for one hour at 400 ℃, then rolled, and the cumulative reduction is 60%. And then water-cooled. Then, performance tests were performed.
In summary, the following steps: the invention discloses an Er-containing magnesium alloy and a preparation method thereof. The chemical components are as follows (atom percentage): er 0.2-2.0%, Y0.2-2.0%, Zn 0.2-2.0%, and Mg and inevitable impurities in balance. The preparation method comprises the following steps: smelting; homogenizing; deforming; and (5) aging treatment. The preparation method comprises the steps of proportioning the components according to the design of alloy elements, smelting under the condition of vacuum or protective atmosphere, casting an alloy ingot or directly casting into a casting, and then selectively carrying out homogenization, deformation and aging treatment according to actual requirements. On the basis of enhancing the mechanical property of the Mg-Y-Zn magnesium alloy by the long-period ordered structure, the Er element is added into the magnesium alloy to replace part of the Y element in the Mg-Y-Zn alloy, so that the content of solid-solution atoms in an alloy matrix phase is effectively regulated, and the LPSO phase composition is regulated, thereby playing the role of regulating and controlling the mechanical property of the magnesium alloy. By designing element content and preparation process. The content of Er in the matrix phase and the type, the appearance and the distribution of the long-period ordered structure reinforcing phase are controlled through homogenization, deformation and aging treatment, so that the microstructure of the alloy is controlled, and the aims of improving the room temperature strength and the shaping of the magnesium alloy are fulfilled.

Claims (2)

1. An Er-containing magnesium alloy is characterized by comprising the following components in atomic percentage: 0.5% of Er, 1% of Y, 1% of Zn, and the balance of Mg and inevitable impurities;
the preparation method of the Er-containing magnesium alloy comprises the following steps: adding pure magnesium ingot, heating the furnace to 720-740 ℃, and introducing SF6：CO2The volume ratio is 1: 200 of protective gas, after the magnesium ingot is completely melted, skimming dross on the surface of the melt, sequentially adding Mg-20Y intermediate alloy and Mg-30Er intermediate alloy, raising the furnace temperature to 750 ℃, after the intermediate alloy is completely melted, preserving the temperature for 15-20 min, pouring the mixture into a pre-preheated mold, casting the mixture into an alloy ingot, preserving the temperature of the alloy for 10h at 520 ℃, then cooling the alloy by water, and testing the room-temperature mechanical properties of the Er-containing magnesium alloy to be 229MPa in tensile strength, 145MPa in yield strength and 25 in elongation percentage.
2. An Er-containing magnesium alloy is characterized by comprising the following components in atomic percentage: 1% of Er, 1% of Y and 1% of Zn, and the balance of Mg and inevitable impurities;
the preparation method of the Er-containing magnesium alloy comprises the following steps: adding pure magnesium ingots, heating the furnace to 720-740 ℃, and introducing SF 6: the volume ratio of CO2 is 1: 200 of protective gas, skimming dross on the surface of the melt after the magnesium ingot is completely melted, sequentially adding Mg-20Y intermediate alloy and Mg-30Er intermediate alloy, raising the furnace temperature to 750 ℃, keeping the temperature for 15-20 min after the intermediate alloy is completely melted, pouring the mixture into a pre-preheated mold, casting the mixture into an alloy ingot, keeping the temperature of the alloy at 520 ℃ for 10h, then cooling the alloy by water, and testing the room-temperature mechanical properties of the Er-containing magnesium alloy to be 239MPa in tensile strength, 155MPa in yield strength and 27% in elongation.
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CN114075637A (en) * 2021-11-18 2022-02-22 重庆大学 Mg-Mn-Er series wrought magnesium alloy and preparation method thereof
CN115418584B (en) * 2022-08-26 2023-04-28 昆明理工大学 Method for improving thermal stability of two-dimensional nano magnesium alloy material

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CN109182858A (en) * 2018-11-14 2019-01-11 哈尔滨工程大学 One kind heat resistance magnesium alloy containing Ho and preparation method thereof

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Publication number Priority date Publication date Assignee Title
CN109182858A (en) * 2018-11-14 2019-01-11 哈尔滨工程大学 One kind heat resistance magnesium alloy containing Ho and preparation method thereof

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Title
Characterization of elevated-temperature high strength and decent thermal conductivity extruded Mg-Er-Y-Zn alloy containing nano-spaced stacking faults;Yan Feng等;《Materials Characterization》;20190717;第1-12页 *

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