WO2022165952A1

WO2022165952A1 - Fe-containing soluble magnesium alloy and preparation method therefor

Info

Publication number: WO2022165952A1
Application number: PCT/CN2021/083339
Authority: WO
Inventors: 刘运腾; 杨帆; 赵东清; 周吉学; 刘洪涛; 吴建华; 宋令慧; 王西涛; 奥玛仕奇雷萨
Original assignee: 山东省科学院新材料研究所
Priority date: 2021-02-02
Filing date: 2021-03-26
Publication date: 2022-08-11
Also published as: CN112921223A; CN112921223B

Abstract

A Fe-containing soluble magnesium alloy and a preparation method therefor. The alloy is an Mg-Nd-Ce-Fe magnesium alloy, and is composed of the following elements by mass percentage: 0.20 to 5.00 wt% of Nd, 0 to 2.00 wt% of Ce, 0.10 to 2.00 wt% of Fe, and the balance being Mg and inevitable impurity elements. The magnesium alloy material can be prepared by means of fusion casting, extrusion and the like, achieving effective regulation and control of structures and components of the material; and the magnesium alloy material also has good mechanical properties and a uniform and stable dissolution rate.

Description

A kind of Fe-containing soluble magnesium alloy and preparation method thereof

technical field

The invention relates to the technical field of metal materials and processing, in particular to a Fe-containing soluble magnesium alloy and a preparation method thereof.

Background technique

The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not necessarily be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person of ordinary skill in the art.

As traditional oil and gas resources are facing depletion, shale oil and gas has gradually become an important direction for the development of the energy field at present and in the future, with high development prospects and economic value. In January, the United States overtook Saudi Arabia to become the world's largest oil exporter. According to statistics, China's shale gas and shale oil reserves are at the forefront of the world, and the future development prospects are broad. However, the relevant mining technologies are still in the starting price range, and staged fracturing technology is commonly used in the current mainstream horizontal well mining. A key component of the technology is the fracturing tool, including temporary plugging balls, ball seats, bridge plugs, and sliding sleeves. The above tools should have solubility and good mechanical properties during the fracturing process.

Commonly used soluble materials are polymer materials, aluminum alloys and magnesium alloys. Among them, soluble magnesium alloys are mostly Mg-Zn, Mg-Al and Mg-RE based on the addition of Cu, Ni and Fe and other elements to form a cathode phase, which can be quickly dissolved in aqueous solution through galvanic corrosion. . At present, magnesium alloys containing Cu and Ni can be prepared by traditional methods such as casting, hot extrusion, heat treatment, etc., while soluble magnesium alloys containing Fe are mostly prepared by powder metallurgy. There are two reasons for this: First, the Mg-Fe master alloy has not yet been seen on the market. During the smelting process, due to the high melting point of Fe, the solubility in the magnesium alloy melt is low, so it is difficult to add; second, Fe is easy to mix with Al. , Zn, Cu, Ni, Mn, Si and other elements form the second phase, which makes the size and distribution of the Fe-containing cathode phase difficult to control, resulting in unstable product performance. In addition, for magnesium alloys, Fe and Zr elements have a similar effect of grain refinement. Therefore, it is an important technical issue to rationally design the composition of Fe-containing magnesium alloys and the way of adding Fe elements and control its distribution in magnesium alloys. Solving this problem is expected to promote the development of high-performance soluble magnesium alloy materials and improve the technical level of shale oil and gas exploitation in my country.

SUMMARY OF THE INVENTION

In view of the deficiencies of the existing Fe-containing soluble magnesium alloy materials prepared by powder metallurgy methods, the present disclosure proposes an Fe-containing soluble magnesium alloy and a preparation method thereof. The magnesium alloy material can be prepared by melting casting, extrusion, etc., and realizes effective regulation of the structure and composition of the material; and also has good mechanical properties and a uniform and stable dissolution rate.

Specifically, the technical solutions of the present disclosure are as follows:

In a first aspect of the present disclosure, a soluble magnesium alloy containing Fe is provided, the alloy is a Mg-Nd-Ce-Fe magnesium alloy, and is composed of the following elements by mass percentage: Nd 0.20-5.00wt%, Ce 0- 2.00wt%, Fe 0.10-2.00wt%, and the rest are Mg and inevitable impurity elements.

In a second aspect of the present disclosure, the present disclosure provides a preparation method of Fe-containing soluble magnesium alloy, comprising:

According to the mass percentage ratio of the above Fe-containing soluble magnesium alloy, weigh pure magnesium ingot, Mg-Nd master alloy, Mg-Ce master alloy, pure iron powder or iron oxide powder; under argon protection, smelt pure magnesium ingot, Mg-Nd master alloy, Mg-Ce master alloy, refining and slag removal, adding pure iron powder or iron oxide powder and casting into ingots at the same time; homogenizing the ingots, cutting into billets of corresponding size and peeling; hot extrusion Pressed into bars; aging treatment.

In a third aspect of the present disclosure, the present disclosure provides an application of a Fe-containing soluble magnesium alloy and/or a preparation method of the Fe-containing soluble magnesium alloy in preparing a fracturing tool for shale oil and gas development.

One or more technical solutions in the present disclosure have the following beneficial effects:

(1) The Mg-Nd-Ce-Fe magnesium alloy of the present disclosure can refine ingot grain size and reduce ingot segregation by adding light rare earth elements Nd and Ce; phase, which can ensure the existence of Fe element in the alloy, which ensures the refinement of the ingot structure and the stability of the dissolution performance to a certain extent.

(2) The Mg-Nd-Ce-Fe magnesium alloy of the present disclosure is prepared by a melting and casting method. Compared with the powder metallurgy method, the internal pores of the material are eliminated, thereby significantly improving the mechanical properties of the material.

(3) There is no low temperature phase in the material of the present disclosure, so the high temperature resistance performance of the material is good, and thermal cracking will not occur in the material during high temperature thermal deformation.

(4) In the preparation process of the disclosed material, Fe is added by pure iron powder or iron oxide in the form of a refining agent, and more Fe is added compared with the traditional smelting method. Therefore, it also has stable properties in a low-salt environment. corrosion rate.

(5) Since Nd has a solid solubility of 3.6 wt % in magnesium alloys, the materials prepared in the present disclosure can be strengthened by heat treatment, so their mechanical properties can be controlled in a wide range and can meet the needs of various environments.

(6) The Fe-containing soluble magnesium alloy prepared by the present disclosure has a tensile strength of 260-380 MPa, an elongation of 14-30%, and a good dissolution rate in a high-salt or low-salt environment at 93°C.

Detailed ways

The present disclosure will be further described below with reference to specific embodiments. It should be understood that these examples are only used to illustrate the present disclosure and not to limit the scope of the present disclosure. In the following examples, the experimental methods without specific conditions are usually in accordance with conventional conditions or in accordance with the conditions suggested by the manufacturer.

Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. The reagents or raw materials used in the present invention can be purchased through conventional channels. Unless otherwise specified, the reagents or raw materials used in the present invention are used in a conventional manner in the art or in accordance with product instructions. In addition, any methods and materials similar or equivalent to those described can be used in the methods of the present invention. Methods and materials for preferred embodiments described herein are provided for illustrative purposes only.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present disclosure. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, and/or combinations thereof.

As described in the background art, when preparing Fe-containing soluble magnesium alloys, it is difficult to prepare Mg-Fe master alloys due to the high melting point of Fe and low solubility in magnesium alloy solutions, and the size of the Fe-containing cathode phase In order to solve the above problems, the present disclosure provides a Fe-containing soluble magnesium alloy and a preparation method thereof.

In an embodiment of the present disclosure, a soluble magnesium alloy containing Fe is provided, and the alloy is a Mg-Nd-Ce-Fe magnesium alloy, which is composed of the following elements by mass percentage: Nd 0.20-5.00wt%, Ce 0-2.00wt%, Fe 0.10-2.00wt%, and the rest are Mg and inevitable impurity elements.

Further, the Fe-containing soluble magnesium alloy is composed of the following elements by mass percentage: Nd 0.20-3.70wt%, Ce 0.50-1.00wt%, Fe 0.50-2.00wt%, and the rest are Mg and inevitable impurity elements .

Further, the Fe-containing soluble magnesium alloy is composed of the following elements by mass percentage: Nd 3.60wt%, Ce 1.00wt%, Fe 1.50wt%, and the rest are Mg and inevitable impurity elements.

Since Fe element cannot form a second phase with magnesium, it has a remarkable grain refining effect. In order to give full play to the effect of Fe elemental heterogeneous nucleation, the addition of elements forming the second phase with Fe is avoided, and Nd and Ce elements are added. Nd and Ce elements belong to light rare earth elements, and the cost is lower than that of heavy rare earth elements. The high melting point second phase formed by Nd, Ce and Mg also has the effect of refining grains.

In one embodiment of the present disclosure, a preparation method of Fe-containing soluble magnesium alloy is provided, comprising:

The solubility of Fe in magnesium alloy melt is low, so it is difficult to prepare by conventional melting process. In the present disclosure, pure iron powder or iron oxide powder is added to the magnesium alloy solution in the form of a refiner before casting. Among them, iron oxide will react with magnesium in magnesia to produce elemental Fe and magnesium oxide, and release heat. The released heat will increase the temperature of the local magnesium alloy melt, thereby increasing the solubility of Fe. The Fe element gradually precipitates and sinks as the casting progresses, so as to achieve the purpose of refining the grains. Magnesium oxide is less dense and will float to the surface of the magnesium melt to form slag.

Further, the specific steps of smelting and pouring into an ingot are: under argon protection, smelting the pure magnesium ingot, the Mg-Nd master alloy and the Mg-Ce master alloy at 720-760°C, and keeping the temperature for 40-60min, Stir for 5-10 minutes; and refine for 20-30 minutes, heat up to 740-780°C for 30-40 minutes after refining, add iron oxide powder at 720-740°C and cast into semi-continuous ingots.

Further, the conditions of the homogenization treatment are to carry out the homogenization treatment at 500-540°C, the holding time is 1-16h, the cooling method is air cooling, and then cut into corresponding blanks and peeled; preferably, the homogenization treatment The condition is that the homogenization treatment is carried out at 520°C for an incubation time of 8h.

Further, the specific conditions of the extrusion are: the extrusion temperature is 380-460°C, the extrusion ratio is 4-10, and the extrusion speed is 0.1-10 m/min; further preferably, the extrusion temperature is 400°C, the extrusion ratio is 4-10 is 8, and the extrusion speed is 5m/min.

Further, the specific conditions of the aging treatment are as follows: at 150-200° C., the temperature is kept for 1-48 hours.

In an embodiment of the present disclosure, an application of a Fe-containing soluble magnesium alloy and/or a preparation method of the Fe-containing soluble magnesium alloy in preparing a fracturing tool for shale oil and gas development is provided.

In order to enable those skilled in the art to understand the technical solutions of the present disclosure more clearly, the technical solutions of the present disclosure will be described in detail below with reference to specific embodiments.

Example 1

A soluble magnesium alloy containing Fe, the alloy is a Mg-Nd-Ce-Fe magnesium alloy, which is composed of the following elements by mass percentage: Nd 3.60wt%, Ce 1.00wt%, Fe 1.50wt%, and the rest are Mg and non-ferrous metals. Avoid impurity elements.

Preparation process: weighing raw materials according to the above proportions: pure magnesium ingot, Mg-30%Nd master alloy, Mg-30%Ce master alloy, iron oxide powder;

Under argon protection, the above pure magnesium ingot, Mg-Nd master alloy, and Mg-Ce master alloy were smelted at 740 °C, kept for 50 min, and stirred for 10 min; and refined for 30 min. After refining, the temperature was raised to 780 °C and left for 40 min. Add iron oxide powder at 740 ℃ and cast into semi-continuous ingot at the same time;

The above-mentioned ingots are homogenized at 540°C for a holding time of 6h, and the cooling method is air cooling, and then cut into corresponding billets and peeled;

The billet obtained in the previous step was extruded into a bar under the conditions of an extrusion temperature of 420°C, an extrusion ratio of 8 and an extrusion speed of 5m/min; and an aging treatment at 180°C for 7 hours.

Example 2

A soluble magnesium alloy containing Fe, the alloy is a Mg-Nd-Ce-Fe magnesium alloy, which is composed of the following elements by mass percentage: Nd 5.0wt%, Ce 2.00wt%, Fe 2.0wt%, and the rest are Mg and non-ferrous metals. Avoid impurity elements.

Weighing raw materials according to the proportion: pure magnesium ingot, Mg-30%Nd master alloy, Mg-30%Ce master alloy, pure iron powder;

Under argon protection, the above pure magnesium ingot, Mg-Nd master alloy, and Mg-Ce master alloy were smelted at 760 °C, kept for 60 min, and stirred for 5 min; and refined for 20 min. Add pure iron powder at 740℃ and cast into semi-continuous ingot;

The above-mentioned ingots are homogenized at 540°C for a holding time of 8h, and the cooling method is air cooling, and then cut into corresponding billets and peeled;

The billet obtained in the previous step was extruded into a bar under the conditions of an extrusion temperature of 460°C, an extrusion ratio of 4 and an extrusion speed of 2m/min; and an aging treatment at 170°C for 10 hours.

Example 3

A soluble magnesium alloy containing Fe, the alloy is a Mg-Nd-Ce-Fe magnesium alloy, which is composed of the following elements by mass percentage: Nd 0.2wt%, Ce 1.00wt%, Fe 0.5wt%, and the rest are Mg and non-ferrous metals. Avoid impurity elements.

Weighing raw materials according to the proportion: pure magnesium ingot, Mg-30%Nd master alloy, Mg-30%Ce master alloy, iron oxide powder;

Under argon protection, the above pure magnesium ingot, Mg-Nd master alloy, and Mg-Ce master alloy were smelted at 740 °C, kept for 40 minutes, stirred for 5 minutes; and refined for 30 minutes, and then heated to 760 °C for 35 minutes. Add iron oxide powder at 750℃ and cast into semi-continuous ingot;

The above-mentioned ingots are homogenized at 500°C for a holding time of 3h, and the cooling method is air cooling, and then cut into corresponding billets and peeled;

The billet obtained in the previous step was extruded into a bar under the conditions of an extrusion temperature of 400° C., an extrusion ratio of 10, and an extrusion speed of 0.5 m/min.

Example 4

A soluble magnesium alloy containing Fe, which is a Mg-Nd-Fe magnesium alloy, is composed of the following elements by mass percentage: Nd 1.0wt%, Fe 0.2wt%, and the rest are Mg and inevitable impurity elements.

Weighing raw materials according to the proportion: pure magnesium ingot, Mg-30%Nd master alloy, iron oxide powder;

Under argon protection, the above pure magnesium ingot and Mg-Nd master alloy were smelted at 740°C, kept for 40 minutes, and stirred for 8 minutes; and refined for 30 minutes. After refining, the temperature was raised to 760°C for 30 minutes, and iron oxide was added at 750°C The powder is simultaneously poured into a semi-continuous ingot;

The above-mentioned ingots are homogenized at 500°C for a holding time of 2h, and the cooling method is air cooling, and then cut into corresponding billets and peeled;

Comparative Example 1

The difference from Example 1 is that the melting and casting process in the alloy preparation method is different. Specifically:

Under argon protection, the above pure magnesium ingot, Mg-Nd master alloy, Mg-Ce master alloy and pure iron powder were smelted at 740°C, kept for 50 minutes, stirred for 10 minutes; refined for 30 minutes, and heated to 780°C after refining. After standing for 40min, cast into semi-continuous ingot at 740℃.

Comparative Example 2

The Mg-Gd-Y-Fe magnesium alloy is composed of the following elements by mass percentage: Gd 5.0wt%, Y 2.00wt%, Fe 2.0wt%, and the rest are Mg and inevitable impurity elements.

Weighing raw materials according to the proportion: pure magnesium ingot, Mg-30% Gd master alloy, Mg-30% Y master alloy, iron oxide powder;

Under the protection of argon, the above pure magnesium ingot, Mg-Gd master alloy and Mg-Y master alloy were smelted at 760 °C, kept for 60 min, stirred for 5 min, and refined for 20 min. Add iron oxide powder at 740 ℃ and cast into semi-continuous ingot at the same time;

Comparative Example 3

Mg-Nd-Ce-Al-Mn-Fe magnesium alloy is composed of the following elements by mass percentage: Nd 0.2wt%, Ce 1.00wt%, Al 3wt%, Mn 1.00wt%, Fe 0.5wt%, and the rest are Mg and inevitable impurity elements.

Weighing raw materials according to the proportion: pure magnesium ingot, pure aluminum ingot, Mg-30%Nd master alloy, Mg-30%Ce master alloy, Mg-10%Mn master alloy, iron oxide powder;

Under argon protection, the pure magnesium ingots, pure aluminum ingots, Mg-Nd master alloys, Mg-Ce master alloys, and Mg-Mn master alloys were melted at 740°C, kept for 40 minutes, stirred for 5 minutes, and refined for 30 minutes. After refining, the temperature was raised to 760°C for 35 minutes, and iron oxide powder was added at 750°C while casting into semi-continuous ingots;

Comparative Example 4

The difference from Example 4 is that the alloy composition is different - Fe element is not contained. The alloy is composed of the following elements by mass percentage: Nd 1.0wt%, and the rest is Mg and inevitable impurity elements.

The mechanical properties and dissolution properties of the alloys of Examples 1-4 and Comparative Examples 1-4 are shown in Table 1, and the mechanical properties test method is performed according to GB T 228.1-2010; the dissolution properties are respectively 93 ° C, 3% KCl aqueous solution (high salt solution) and 93°C, 0.1% aqueous KCl solution (low salt solution).

Table 1 Mechanical properties of magnesium alloys at room temperature and dissolution rate at 93 °C

Comparing the examples with the comparative examples, it can be seen that the tensile strength of the Fe-containing soluble magnesium alloy prepared by the present disclosure is 260-380 MPa, the elongation is 14-30%, and the alloys are all in a high-salt or low-salt environment at 93°C. Has a good dissolution rate.

From the comparison of the specific cases above, it can be seen that the preparation process or chemical composition of Comparative Examples 1-4 and Examples 1-4 are respectively different, and the mechanical properties and dissolution rates of the materials prepared in the Comparative Examples are significantly decreased.

In summary, the present disclosure prepares a Fe-containing soluble magnesium alloy material with good mechanical properties and good solubility in both high-salt and low-salt environments, which can meet the requirements of soluble magnesium alloy components for shale oil and gas development. need.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still understand the foregoing embodiments. The technical solutions described are modified, or some technical features thereof are equivalently replaced. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

A soluble magnesium alloy containing Fe, characterized in that the alloy is a Mg-Nd-Ce-Fe magnesium alloy, which is composed of the following elements by mass percentage: Nd 0.20-5.00wt%, Ce 0-2.00wt%, Fe 0.10-2.00wt%, and the rest are Mg and inevitable impurity elements.
The Fe-containing soluble magnesium alloy according to claim 1, characterized in that it is composed of the following elements by mass percentage: Nd 0.20-3.70wt%, Ce 0.50-1.00wt%, Fe 0.50-2.00wt%, and the rest are Mg and inevitable impurity elements.
The Fe-containing soluble magnesium alloy according to claim 1 is characterized in that, it is composed of the following elements by mass percentage: Nd 3.60wt%, Ce 1.00wt%, Fe 1.50wt%, and the rest are Mg and inevitable impurity elements .
A preparation method of Fe-containing soluble magnesium alloy, characterized in that, comprising: weighing pure magnesium ingot, Mg-Nd according to the mass percentage ratio of Fe-containing soluble magnesium alloy described in any one of claims 1-3 Master alloy, Mg-Ce master alloy, pure iron powder or iron oxide powder; under argon protection, smelt pure magnesium ingot, Mg-Nd master alloy, Mg-Ce master alloy, refine and remove slag, add pure iron powder or oxidize The iron powder is cast into ingots at the same time; the ingots are homogenized, cut into billets of corresponding size and peeled; hot-extruded into bars; aging treatment.
The preparation method of Fe-containing soluble magnesium alloy as claimed in claim 4, wherein the concrete steps of smelting and pouring into an ingot are: under argon protection conditions, the pure magnesium ingot, Mg-Nd master alloy, Mg-Ce master alloy, smelted at 720～760℃, kept for 40～60min, stirred for 5～10min; and refined for 20～30min, heated up to 740～780℃ for 30～40min after refining, added pure Iron powder or iron oxide powder is simultaneously cast into a semi-continuous ingot.
The preparation method of Fe-containing soluble magnesium alloy according to claim 4, characterized in that, the condition of the homogenization treatment is to carry out the homogenization treatment at 500-540°C, the holding time is 1-16h, and the cooling method is wind Cold, then cut into corresponding billets and peeled.
The preparation method of Fe-containing soluble magnesium alloy according to claim 4, wherein the specific conditions of the extrusion are: extrusion temperature of 380-460°C, extrusion ratio of 4-10, extrusion speed of 0.1- 10m/min.
The preparation method of Fe-containing soluble magnesium alloy according to claim 7, wherein the extrusion temperature is 400° C., the extrusion ratio is 8, and the extrusion speed is 5 m/min.
The preparation method of Fe-containing soluble magnesium alloy according to claim 4, characterized in that, the specific conditions of the aging treatment are as follows: at 150-200° C., the temperature is kept for 1-48 hours.
The preparation method of the Fe-containing soluble magnesium alloy described in any one of claims 1-3 and/or the preparation method of the Fe-containing soluble magnesium alloy described in any one of claims 4-9 is used to prepare fracturing for shale oil and gas development application in the tool.