阅读说明：本技术 一种含有共晶组织的铜钛合金及其制备方法 (Copper-titanium alloy containing eutectic structure and preparation method thereof ) 是由 王聪 刘超 范永刚 于 2020-12-09 设计创作，主要内容包括：本发明的一种含有共晶组织的铜钛合金及其制备方法,合金按质量百分比由以下组分制备而成：Cu粉：40％～55％,Ti粉：45％～60％；Cu粉和Ti粉质量百分比之和为100％。制备时,按合金组分形成混合物料后,高温真空炉以8-10℃/min的速率,由室温升温至1000-1100℃,保温30-40min,然后在900-910℃保温30-40min,待高温真空炉冷却到室温后,取出,制得含有共晶组织的铜钛合金。该方法工艺简单,获得的共晶组织是由CuTi和CuTi-2两种金属间化合物组成,具有较高的室温断裂韧性,高达30-37MPa·m～(1/2)。(The invention relates to a copper-titanium alloy containing an eutectic structure and a preparation method thereof, wherein the alloy is prepared from the following components in percentage by mass: cu powder: 40-55%, Ti powder: 45% -60%; the sum of the mass percentages of the Cu powder and the Ti powder is 100 percent. During preparation, after forming a mixed material according to the alloy components, the temperature of the high-temperature vacuum furnace is raised from room temperature to 1000-plus-one temperature of 1100 ℃ at the speed of 8-10 ℃/min, the temperature is kept for 30-40min, then the temperature is kept for 30-40min at 900-plus-one temperature of 910 ℃, and the high-temperature vacuum furnace is taken out after being cooled to the room temperature, so that the copper-titanium alloy containing the eutectic structure is prepared. The method has simple process, and the obtained eutectic structure is composed of CuTi and CuTi 2 Two intermetallic compounds with high room temperature fracture toughness up to 30-37 MPa.m 1/2 。)

1. The copper-titanium alloy containing the eutectic structure is characterized by being prepared from the following components in percentage by mass: cu powder: 40-55%, Ti powder: 45% -60.0%; the sum of the mass percentages of the Cu powder and the Ti powder is 100 percent.

2. The copper-titanium alloy with the eutectic structure as claimed in claim 1, wherein the Cu powder has a particle size of 300 mesh and the Ti powder has a particle size of 250 mesh.

3. The copper-titanium alloy with a eutectic structure according to claim 1, wherein said copper-titanium alloy with a eutectic structure has a room temperature fracture toughness of 30-37 MPa-m^1/2。

4. The Cu-Ti alloy with eutectic structure according to claim 1, wherein the room temperature structure of the Cu-Ti alloy with eutectic structure is CuTi and CuTi₂A eutectic structure composed of two intermetallic compounds.

5. The method of producing a copper-titanium alloy containing a eutectic structure according to claim 1, comprising the steps of:

step 1, mixing materials:

according to the component proportion of the copper-titanium alloy, Cu powder: 40-55%, Ti powder: 45% -60.0%; the sum of the mass percentages of the Cu powder and the Ti powder is 100%, and the Cu powder and the Ti powder are uniformly mixed to prepare a mixture;

step 2, preparation smelting:

putting the mixture into a high-temperature vacuum furnace for smelting, wherein the vacuum degree in the furnace is 1.0 multiplied by 10^-3Pa；

Step 3, smelting:

heating the alloy to 1100 ℃ from room temperature at the rate of 8-10 ℃/min, preserving the heat for 30-40min, then preserving the heat for 30-40min at 910 ℃ from 900-.

The technical field is as follows:

the invention belongs to the technical field of metallurgy, and particularly relates to a copper-titanium alloy containing an eutectic structure and a preparation method thereof.

Background art:

copper is a metal with conductivity second only to silver and is less expensive, but pure copper has poor mechanical properties. Titanium and its alloys have excellent properties such as high specific strength, good heat resistance and corrosion resistance, etc. and are used as indispensable structural materials in the modern aerospace industry. Generally, alloying, heat treatment, large deformation, etc. are generally used to improve the mechanical properties of the alloy. No toxic substance is generated in the production process of the copper-titanium alloy, and the copper-titanium alloy is green, environment-friendly and availableThe brazing filler metal between brazing ceramics and between ceramics and metals is used as a structural material and has higher strength, hardness and elasticity, good heat resistance, fatigue resistance, corrosion resistance and the like; as a biological material, the biological material has good biocompatibility and can also play an antibacterial role. As a structural member of a bearing part, the fatigue strength is an important index, and the improvement of the fatigue resistance of the material is particularly important for improving the service life of the part. In general, the higher the tensile strength of a material, the higher its fatigue strength. The copper-titanium alloy with the titanium content lower than 6.1at percent belongs to aging strengthening alloy, and Cu can be regulated and controlled in a heat treatment mode₄The Ti phase further regulates and controls the comprehensive performance of the alloy, and the alloy in the composition range has better mechanical property. However, in this case, the main phase composition of the alloy is that titanium atoms are dissolved in a copper matrix in a solid solution, which increases electron scattering and significantly reduces the electrical conductivity of the alloy.

In the existing research on copper-titanium alloy, most of the research focuses on the research on solid solution of copper and solid solution of titanium, and relatively few researches on intermetallic compounds formed by copper and titanium are carried out. The metal atoms in the intermetallic compound can form metal bonds, ionic bonds and covalent bonds when being combined with each other, and show the characteristic of long-range order, and the intermetallic compound has the properties of high melting point, low density, excellent oxidation resistance, corrosion resistance and the like due to the unique bonding characteristic. The related research shows that CuTi and CuTi in all intermetallic compounds of the copper-titanium alloy₂Can improve the shearing strength of the brazing material, and the CuTi has strong mechanical property₂Has high hardness. As is well known, the microstructure determines the alloy properties, and among various microstructures of the alloy, the eutectic structure is a nearly equilibrium structure which can withstand the temperature up to the eutectic point, and is a good substitute for high-temperature alloys, and generally, the eutectic structure has a very fine structure, and the phases inside the eutectic structure are interlaced and nested with each other to form a network structure, so that the material shows excellent mechanical properties, and also has many other excellent characteristics: (1) good fluidity, and reduced casting defects; (2) a controllable microstructure; (3) good high temperature creep resistance and the like.

In view of the abovePreparing CuTi and CuTi with room temperature tissues₂On the basis of the copper-titanium alloy, the copper-titanium alloy is obtained by regulating and controlling the content, the size, the micro-morphology and the like of two phases, or the copper-titanium alloy with more excellent comprehensive performance is obtained.

The invention content is as follows:

the invention aims to overcome the defects in the prior art and provides a copper-titanium alloy containing an eutectic structure and a preparation method thereof. The alloy is an alloy containing a eutectic structure formed by two intermetallic compounds. The invention adopts copper powder and titanium powder to prepare the copper-titanium alloy containing eutectic structures, the highest heating temperature is 1100 ℃, the melting point of the copper powder is about 1086 ℃, the melting point of the titanium powder is about 1670 ℃, and the alloy related in the invention forms a copper-titanium alloy containing CuTi phase and CuTi phase by means of solid (titanium powder) liquid (copper) diffusion₂Eutectic structure of phase, when the copper powder is completely melted into liquid, the titanium powder is wrapped by the liquid copper to form CuTi and CuTi simultaneously₂The reaction equation of the alternately grown latticed eutectic structure is L → CuTi + CuTi₂. The invention adopts two pure metal powders as raw materials, which can ensure that the two powders are fully diffused at high temperature. In addition, the raw materials are all two required metals, and redundant impurities, air holes and the like are not generated; the heat preservation time is 30min, and the solid-liquid diffusion and nucleation can be completed in sufficient time. In conclusion, the eutectic alloy prepared by the method has uniform structural components, high utilization rate of raw materials, few defects such as air holes and the like, and excellent comprehensive performance, particularly has excellent room temperature fracture toughness which is 30-37 MPa.m^1/2。

In order to achieve the purpose, the invention adopts the following technical scheme:

the copper-titanium alloy containing the eutectic structure is prepared from the following components in percentage by mass: cu powder: 40.0-55%, Ti powder: 45% -60%; the sum of the mass percentages of the Cu powder and the Ti powder is 100 percent.

The granularity of the Cu powder is 300 meshes, and the granularity of the Ti powder is 250 meshes.

The room temperature fracture toughness of the copper-titanium alloy containing the eutectic structure is 30-37 MPa.m^1/2。

The room temperature structure of the copper-titanium alloy is CuTi and CuTi₂A eutectic structure composed of two intermetallic compounds.

The preparation method of the copper-titanium alloy containing the eutectic structure comprises the following steps:

step 1, mixing materials:

mixing Cu powder and Ti powder for 1 hour by using a three-dimensional mixer according to the component proportion of a copper-titanium alloy to prepare a mixture A;

step 2, preparation smelting:

placing the mixture A into a zirconia crucible with the diameter of 40mm and the height of 50mm, and placing the zirconia crucible into a high-temperature vacuum furnace for smelting, wherein the vacuum degree in the furnace is 1.0 multiplied by 10^-3Pa；

Step 3, smelting:

heating the alloy to 1100 ℃ from room temperature at the rate of 8-10 ℃/min, preserving the heat for 30-40min, then preserving the heat for 30-40min at 910 ℃ from 900-.

Compared with the existing copper-titanium alloy, the copper-titanium alloy has the beneficial effects that:

(1) the copper-titanium alloy prepared by the invention has higher room temperature fracture toughness and excellent comprehensive performance.

(2) The copper-titanium binary eutectic alloy is formed by solid-liquid diffusion, the preparation process is simple to operate, the heating temperature is low, and the cost is saved.

(3) The copper-titanium alloy has a eutectic structure at room temperature, and the eutectic structure is formed by CuTi and CuTi₂Two intermetallic compounds.

Description of the drawings:

FIG. 1 is a room temperature SEM image of a copper-titanium alloy prepared in example 1 of the present invention;

FIG. 2 is a room temperature SEM image of a copper-titanium alloy prepared in example 2 of the present invention;

FIG. 3 is a room temperature SEM image of a copper-titanium alloy prepared in example 3 of the present invention;

FIG. 4 is a room temperature SEM image of a copper-titanium alloy prepared according to comparative example 1-1 of the present invention;

FIG. 5 is a room temperature SEM image of a copper-titanium alloy prepared according to comparative example 3-2 of the present invention;

FIG. 6 is a room temperature SEM image of the copper-titanium alloy prepared in comparative examples 3-3 of the present invention.

The specific implementation mode is as follows:

the present invention will be further described with reference to specific embodiments, but the present invention is not limited to these examples.

Example 1

The copper-titanium alloy is prepared from the following components in percentage by mass: cu powder: 52.5 percent of Ti powder and 47.5 percent of Ti powder; the sum of the mass percentages of the Cu powder and the Ti powder is 100 percent.

The Cu powder is 300 meshes, and the Ti powder is 250 meshes.

The room temperature structure of the copper-titanium alloy is hypoeutectic alloy consisting of two copper-titanium intermetallic compounds, and the room temperature fracture toughness is 32 MPa.m^1/2。

The preparation method of the copper-titanium alloy comprises the following steps:

step 1, mixing materials:

according to the component proportion of the copper-titanium alloy, uniformly mixing Cu powder and Ti powder by using a three-dimensional mixer for 1 hour to obtain a mixture A;

step 2, preparation smelting:

40g of the mixture A is put into a zirconia crucible with the diameter of 40mm and the height of 50mm, and the zirconia crucible is put into a high-temperature vacuum furnace for smelting, wherein the vacuum degree in the furnace is 1.0 multiplied by 10^-3Pa。

Step 3, smelting:

heating to 1100 deg.C at a rate of 10 deg.C/min from room temperature, maintaining for 30min, maintaining at 910 deg.C for 30min, cooling to room temperature in a high temperature vacuum furnace, taking out to obtain copper-titanium alloy containing eutectic structure, wherein the SEM image at room temperature is shown in FIG. 1, and CuTi can be seen₂And a eutectic structure formed by interweaving the two parts.

Comparative examples 1 to 1

The difference from the example 1 is that the preparation process is adjusted to ' the temperature of 1100 ℃ is kept for 30min ' and ' the temperature of 1150 ℃ is kept for 60min", the SEM image of the prepared copper-titanium alloy at room temperature is shown in FIG. 4, and polygonal CuTi can be seen₂The crystal grains are dispersed in the CuTi phase and have no mutually-interwoven eutectic structures, and the detection shows that the fracture toughness of the prepared copper-titanium alloy at room temperature is 20 MPa-m^1/2。

Comparative examples 1 to 2

The difference from example 1 is that the alloy composition was adjusted to "Cu powder: 57% and 43% of Ti powder. The room temperature tissue is CuTi and CuTi₂And Cu₄Ti₃Copper-titanium alloy. The detection shows that the room temperature fracture toughness of the prepared copper-titanium alloy is 27 MPa-m^1/2。

Example 2

The copper-titanium alloy is prepared from the following components in percentage by mass: cu powder: 50.0 percent of Ti powder and 50.0 percent of Ti powder; the sum of the mass percentages of the Cu powder and the Ti powder is 100 percent.

The Cu powder is 300 meshes, and the Ti powder is 250 meshes.

The room temperature structure of the copper-titanium alloy is eutectic alloy consisting of two copper-titanium intermetallic compounds, and the room temperature fracture toughness is 37 MPa.m^1/2。

The preparation method of the copper-titanium alloy comprises the following steps:

step 1, mixing materials:

according to the component proportion of the copper-titanium alloy, uniformly mixing Cu powder and Ti powder by using a three-dimensional mixer for 1 hour to obtain a mixture A;

step 2, preparation smelting:

40g of the mixture A is put into a zirconia crucible with the diameter of 40mm and the height of 50mm, and the zirconia crucible is put into a high-temperature vacuum furnace for smelting, wherein the vacuum degree in the furnace is 1.0 multiplied by 10^-3Pa。

Step 3, smelting:

heating to 1100 deg.C at a rate of 10 deg.C/min from room temperature, maintaining for 30min, maintaining at 910 deg.C for 30min, cooling to room temperature in a high temperature vacuum furnace, taking out to obtain copper-titanium alloy containing eutectic structure, wherein the SEM image at room temperature is shown in FIG. 2, which shows that fine CuTi and CuTi₂Formed by two phases being interlaced with each otherTypical room temperature eutectic texture morphology.

Comparative example 2-1

The difference from example 2 is that the "1100 ℃ temperature preservation for 30 min" is adjusted to "1150 ℃ temperature preservation for 60 min" in the preparation process, and the SEM image of the prepared copper-titanium alloy at room temperature is shown in FIG. 5, which shows that CuTi₂The grains are coarse, the typical eutectic microstructure micro morphology is not mutually interwoven, and the detection shows that the fracture toughness of the prepared copper-titanium alloy at room temperature is 24 MPa.m^1/2。

Example 3

The copper-titanium alloy is prepared from the following components in percentage by mass: cu powder: 45.0 percent of Ti powder and 55.0 percent of Ti powder; the sum of the mass percentages of the Cu powder and the Ti powder is 100 percent.

The Cu powder is 300 meshes, and the Ti powder is 250 meshes.

The room temperature structure of the copper-titanium alloy is hypereutectic alloy consisting of two copper-titanium intermetallic compounds, and the room temperature fracture toughness is 30 MPa.m^1/2。

The preparation method of the copper-titanium alloy comprises the following steps:

step 1, mixing materials:

according to the component proportion of the copper-titanium alloy, uniformly mixing Cu powder and Ti powder by using a three-dimensional mixer for 1 hour to obtain a mixture A;

step 2, preparation smelting:

40g of the mixture A is put into a zirconia crucible with the diameter of 40mm and the height of 50mm, and the zirconia crucible is put into a high-temperature vacuum furnace for smelting, wherein the vacuum degree in the furnace is 1.0 multiplied by 10^-3Pa。

Step 3, smelting:

heating to 1100 deg.C at a rate of 10 deg.C/min from room temperature, maintaining for 30min, maintaining at 910 deg.C for 30min, cooling to room temperature in a high temperature vacuum furnace, taking out to obtain copper-titanium alloy containing eutectic structure, wherein the room temperature SEM picture is shown in FIG. 3, and it can be seen that the room temperature structure is composed of CuTi and CuTi₂Mutually wrapped and interwoven to form a eutectic structure.

Comparative example 3-1

The difference from example 3 is that, in the following,the preparation process adjusts the '1100 ℃ heat preservation for 30 min' to '1150 ℃ heat preservation for 60 min' to obtain the copper-titanium alloy CuTi₂The grain size is not uniform, no typical eutectic structure is generated, almost no eutectic structure appears, and the prepared copper-titanium alloy has the room temperature fracture toughness of 22 MPa-m through detection^1/2。

Comparative examples 3 to 2

The difference from example 3 is that the "1100 ℃ temperature preservation for 30 min" is adjusted to "1100 ℃ temperature preservation for 20 min" in the preparation process, the SEM image of the prepared copper-titanium alloy at room temperature is shown in FIG. 5, it can be seen that undissolved Ti exists, and the obtained alloy at room temperature structure contains CuTi and CuTi₂And alpha Ti, and the prepared copper-titanium alloy has room temperature fracture toughness of 23 MPa-m^1/2。

Comparative examples 3 to 3

The difference from example 3 is that the "1100 ℃ temperature preservation for 30min and the 910 ℃ temperature preservation for 30 min" is adjusted to "1100 ℃ temperature preservation for 60 min" in the preparation process, the SEM image of the prepared copper-titanium alloy at room temperature is shown in FIG. 6, it can be seen that eutectic structures can not be obtained, and the detection shows that the fracture toughness of the prepared copper-titanium alloy at room temperature is 25 MPa.m^1/2。

Comparative examples 3 to 4

The difference from example 3 is that the alloy composition was adjusted to "Cu powder: 39% and 61% of Ti powder. A titanium alloy containing a second phase, which was obtained by the method of example and had an as-cast room-temperature structure of alpha Ti and a second phase of CuTi₂The detection shows that the prepared product is titanium alloy, and the room temperature fracture toughness is 26 MPa.m^1/2。