Rare earth silver copper alloy and preparation method and application thereof

Abstract

The invention discloses a rare earth silver copper alloy and a preparation method and application thereof. The rare earth silver-copper alloy comprises the following components: based on 100 parts by weight of the rare earth silver-copper alloy, 3-25 parts by weight of Cu, 0.2-3 parts by weight of LaCe and the balance of Ag and inevitable impurities, wherein the weight ratio of La to Ce is 1: (1-3). The rare earth silver-copper alloy has good mechanical properties.

Description

Technical Field

[0001] This invention relates to a rare earth silver-copper alloy, its preparation method, and its uses. Background Technology

[0002] Silver alloys have important applications in fields such as medical, electrical contact materials and aerospace due to their excellent electrical and thermal conductivity.

[0003] CN112059468A discloses a silver-based solder alloy, comprising, by mass percentage: Cu, 26-28%; Ga, 3.5-5.5%; at least two of the following elements: Ni, 0.001-0.5%; Co, 0.001-0.5%; Fe, 0.001-0.5%; at least one of the following elements: Au, 0.001-0.5%; Pt, 0.001-0.5%; Pd, 0.001-0.5%; at least one of the following elements: In, 0.001-0.5%; Sn, 0.001-0.5%; at least one of the following elements: La, Ce, Pr, Nd, Sm, Eu, Er, Yb, Y, and Sc; with the balance being Ag.

[0004] CN119426846A discloses an active solder for sealing sapphire and Kovar alloy and its preparation method. The active solder contains 25.0–27.5 wt% Cu, 1.0–6.0 wt% Ti, 1.0–5.0 wt% Al, 0.1–1.0 wt% B, and 0.1–0.5 wt% rare earth element RE, where RE is one or more of La, Ce, Sc, Pr, Nd, and Er, with the balance being Ag. The preparation method includes: preparing silver-based pre-alloyed powder using gas atomization; mixing the alloy powder with additive element powder by ball milling; obtaining an alloy ingot by vacuum pressure sintering; and obtaining an active solder strip with a thickness of 0.05–0.2 mm through rough rolling, intermediate annealing, and finish rolling.

[0005] The two documents mentioned above use a wide variety of elements but do not cover properties such as tensile strength and yield strength.

[0006] CN103805799A discloses a rare earth silver-copper alloy for ultrafine silver enameled wire and its production process. The raw material components of this rare earth silver-copper alloy, by weight percentage, are: silver 99.45–99.75%, copper 0.235–0.545%, and cerium 0.005–0.015%. The production process includes the following steps: preparing silver, copper, and cerium according to the mass ratio; first, adding silver to a continuous furnace and heating it to 961–980℃ to melt it into molten silver; adding copper and cerium to the molten silver and heating it to 20–40℃, then maintaining the temperature for 15–25 minutes; evacuating the continuous casting furnace for 8–12 minutes, then allowing it to stand for 8–12 minutes; and then horizontally continuous casting to obtain rare earth silver-copper rods. This rare earth silver-copper alloy has a low copper content and relatively low strength. Summary of the Invention

[0007] In view of this, one object of the present invention is to provide a rare earth silver-copper alloy containing only Cu, La, Ce, and Ag, which has good mechanical properties, especially high tensile strength, yield strength, and elongation. Another object of the present invention is to provide a method for preparing the rare earth silver-copper alloy. A further object of the present invention is to provide the use of lanthanum and cerium in improving the mechanical properties of silver-copper alloys.

[0008] The present invention achieves the above objectives using the following technical solutions.

[0009] On one hand, the present invention provides a rare earth silver-copper alloy having the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 3 to 25 parts by weight, LaCe is 0.2 to 3 parts by weight, and the balance is Ag and unavoidable impurities;

[0010] The weight ratio of La to Ce is 1:1 to 3.

[0011] According to the rare earth silver-copper alloy of the present invention, preferably, the rare earth silver-copper alloy has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 5 to 20 parts by weight, LaCe is 0.2 to 2 parts by weight, and the balance is Ag and unavoidable impurities.

[0012] The weight ratio of La to Ce is 1:1 to 3.

[0013] According to the rare earth silver-copper alloy of the present invention, preferably, the rare earth silver-copper alloy has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 5 to 15 parts by weight, LaCe is 0.2 to 1.5 parts by weight, and the balance is Ag and unavoidable impurities.

[0014] The weight ratio of La to Ce is 1:1 to 3.

[0015] According to the rare earth silver-copper alloy of the present invention, preferably, the rare earth silver-copper alloy has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 5 to 12 parts by weight, LaCe is 0.2 to 1 part by weight, and the balance is Ag and unavoidable impurities.

[0016] The weight ratio of La to Ce is 1:1 to 3.

[0017] According to the rare earth silver-copper alloy of the present invention, preferably, the rare earth silver-copper alloy has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 6 to 10 parts by weight, LaCe is 0.3 to 0.8 parts by weight, and the balance is Ag and unavoidable impurities.

[0018] The weight ratio of La to Ce is 1:1 to 2.

[0019] On the other hand, the present invention also provides a method for preparing the rare earth silver-copper alloy as described above, comprising the following steps:

[0020] 1) Prepare raw materials pure silver, pure copper, lanthanum and cerium according to the composition of the rare earth silver-copper alloy; wherein, lanthanum is derived from elemental lanthanum metal or lanthanum-cerium metal, and cerium is derived from elemental cerium metal or lanthanum-cerium metal.

[0021] 2) Melt pure silver and pure copper at 820-970℃ and remove surface slag to obtain the initial melt;

[0022] 3) Add lanthanum and cerium to the initial melt, then heat to 860-1050℃ and hold at 860-1050℃ for 30-65 minutes to obtain the final melt; cast the final melt to obtain an alloy ingot.

[0023] 4) The alloy ingot obtained in step 3) is hot-extruded at 400-560°C, with an extrusion ratio of 6-10:1 and an extrusion rate of 4-9 mm / min to obtain the rare earth silver-copper alloy.

[0024] According to the preparation method of the present invention, preferably, the following step is further included between step 1) and step 2): preheating pure silver, pure copper, lanthanum and cerium at 180-250°C for 30-80 min to obtain preheated pure silver, pure copper, lanthanum and cerium.

[0025] According to the preparation method of the present invention, preferably, in step 2), preheated pure silver and pure copper are placed in a graphite crucible, and then the graphite crucible is placed in a resistance furnace to melt the pure silver and pure copper to obtain an initial melt.

[0026] According to the preparation method of the present invention, preferably, in step 3), the casting mold is preheated to 250-350°C before casting the final melt; in step 4), the extrusion ratio is 7-9:1 and the extrusion rate is 5-8 mm / min.

[0027] Furthermore, the present invention also provides the use of lanthanum and cerium in improving the mechanical properties of silver-copper alloys.

[0028] The rare-earth silver-copper alloy of the present invention, with a specific composition, exhibits high tensile strength, yield strength, and elongation. The preparation method of the present invention is more advantageous for obtaining rare-earth silver-copper alloys with superior mechanical properties. Attached Figure Description

[0029] Figure 1(a) and Figure 1(b) are SEM images of the rare earth silver-copper alloy obtained in Example 1.

[0030] Figure 2 The image shows the XRD pattern of the rare earth silver-copper alloy obtained in Example 1. Detailed Implementation

[0031] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0032] Rare Earth Silver-Copper Alloy

[0033] This invention provides a rare-earth silver-copper alloy containing only Ag, Cu, La, and Ce. It may contain unavoidable impurities. The rare-earth silver-copper alloy has the following composition: based on 100 parts by weight of the rare-earth silver-copper alloy, Cu is 3-25 parts by weight, La and Ce are 0.2-3 parts by weight, and the balance is Ag and unavoidable impurities; wherein the weight ratio of La to Ce is 1:1-3. Such a rare-earth silver-copper alloy exhibits further improvements in tensile strength, yield strength, and elongation.

[0034] In this invention, Cu is copper element. Based on 100 parts by weight of rare earth silver-copper alloy, the amount of Cu can be 3 to 25 parts by weight, preferably 5 to 20 parts by weight, more preferably 5 to 15 parts by weight, even more preferably 5 to 12 parts by weight, and even more preferably 6 to 10 parts by weight.

[0035] In this invention, La represents lanthanum and Ce represents cerium. Based on 100 parts by weight of a rare-earth silver-copper alloy, the amount of La and Ce can be 0.2 to 3 parts by weight, preferably 0.2 to 2 parts by weight, more preferably 0.2 to 1.5 parts by weight, even more preferably 0.2 to 1 part by weight, and even more preferably 0.3 to 0.8 parts by weight. The weight ratio of La to Ce is 1:1 to 3.

[0036] In some embodiments, the weight ratio of La to Ce is 1:2. In other embodiments, the weight ratio of La to Ce is 1.2:2.2.

[0037] According to one embodiment of the present invention, based on 100 parts by weight of a rare earth silver-copper alloy, Cu is 5 to 20 parts by weight, LaCe is 0.2 to 2 parts by weight, and the balance is Ag and unavoidable impurities; wherein the weight ratio of La to Ce is 1:1 to 3.

[0038] According to another embodiment of the present invention, based on 100 parts by weight of a rare earth silver-copper alloy, Cu is 6 to 10 parts by weight, La and Ce are 0.3 to 0.8 parts by weight, and the balance is Ag and unavoidable impurities; wherein the weight ratio of La to Ce is 1:1 to 3.

[0039] According to another embodiment of the present invention, based on 100 parts by weight of a rare earth silver-copper alloy, Cu is 6 to 8 parts by weight, LaCe is 0.3 to 0.6 parts by weight, and the balance is Ag and unavoidable impurities; wherein the weight ratio of La to Ce is 1:1 to 3.

[0040] According to a specific embodiment of the present invention, based on 100 parts by weight of a rare earth silver-copper alloy, Cu is 7 to 7.5 parts by weight, La and Ce are 0.34 to 0.4 parts by weight, and the balance is Ag and unavoidable impurities; wherein, the weight ratio of La to Ce is 1:1 to 3.

[0041] The rare-earth silver-copper alloy of the present invention has a tensile strength greater than or equal to 450 MPa, preferably greater than or equal to 455 MPa, more preferably greater than or equal to 465 MPa, and up to 478 MPa. Its yield strength is greater than or equal to 240 MPa, preferably greater than or equal to 245 MPa, more preferably greater than or equal to 249 MPa, and up to 253 MPa. Its elongation is greater than 30%, preferably greater than or equal to 31%, and up to 32%.

[0042] <Preparation Methods of Rare Earth Silver-Copper Alloys>

[0043] The method for preparing the rare earth silver-copper alloy of the present invention may include the following steps: (1) raw material preparation step; (2) initial melt formation step; (3) final melt formation and casting step; and (4) hot extrusion step. These are described in detail below.

[0044] Raw material preparation steps

[0045] The raw materials are prepared according to the specific composition of the rare earth silver-copper alloy as described above. The raw materials are pure silver, pure copper, lanthanum, and cerium.

[0046] Pure silver can be in the form of pure silver ingots, pure silver powder, or pure silver rods; pure copper can be in the form of pure copper ingots, pure copper powder, or pure copper rods. Pure silver refers to silver with a purity greater than 99.9%, and pure copper refers to copper with a purity greater than 99.9%.

[0047] Lanthanum is derived from elemental lanthanum or lanthanum-cerium metal. Cerium is derived from elemental cerium or lanthanum-cerium metal. Lanthanum-cerium metal refers to lanthanum-cerium alloys.

[0048] In some embodiments, lanthanum is elemental lanthanum metal, which can be lanthanum powder or lanthanum ingots. In other embodiments, lanthanum is derived from lanthanum and cerium metals.

[0049] In some embodiments, cerium is elemental cerium metal, which can be cerium powder or cerium blocks. In other embodiments, cerium is derived from lanthanum cerium metal.

[0050] In this invention, the purity of lanthanum or cerium elemental metal is greater than 99%. The purity of lanthanum and cerium metal is greater than 99%.

[0051] Initial melt formation steps

[0052] Pure silver and pure copper are melted at 820–970℃, and surface slag is removed to obtain the initial melt. This process helps to improve the strength of the resulting rare-earth silver-copper alloy.

[0053] In this invention, pure silver, pure copper, lanthanum, and cerium can be preheated separately at 180–250°C for later use. The preheating temperature can be 180–250°C, preferably 190–240°C, and more preferably 200–230°C. This helps to remove moisture from the surfaces of the pure silver and pure copper, thus avoiding affecting the purity and strength of the final product.

[0054] In this invention, preheating can be performed in an inert atmosphere. The inert atmosphere can be one or more of nitrogen, neon, and argon. According to one embodiment of the invention, preheating is performed in an argon atmosphere.

[0055] In this invention, preheated pure silver and pure copper are first melted. The raw materials are melted in a melting vessel. The melting vessel can be a crucible, such as a graphite crucible. The temperature inside the graphite crucible is 820–970°C.

[0056] According to a specific embodiment of the present invention, preheated pure silver and pure copper are placed in a graphite crucible, which is then placed in an electric resistance furnace to melt the pure silver and pure copper. Surface slag is removed to obtain an initial melt. The melting temperature can be 820–970°C, preferably 820–950°C, and more preferably 850–950°C. A certain degree of vacuum can be maintained during melting, which can be less than 50 Pa, preferably less than 10 Pa, and more preferably less than or equal to 1 Pa.

[0057] In this invention, no slagging agent is used to remove surface scum.

[0058] Final melt formation and casting steps

[0059] Lanthanum and cerium are added to the initial melt, which is then heated to 860–1050 °C and held at 860–1050 °C for 30–65 min to obtain the final melt. The final melt is then cast to obtain an alloy ingot. This process is beneficial for improving the mechanical properties of the resulting rare earth silver-copper alloy.

[0060] The holding temperature (i.e., the temperature of the melt) can be 860–1050℃, preferably 900–1000℃, and more preferably 950–980℃. The holding time can be 30–65 min, preferably 30–60 min, for example, 30 min, 40 min, 50 min, or 60 min.

[0061] According to one embodiment of the present invention, the casting mold is preheated to 250–350°C before the final melt is cast. The preheating temperature is preferably 280–350°C, more preferably 300–330°C. This is beneficial for obtaining rare-earth silver-copper alloys with good mechanical properties.

[0062] Hot extrusion steps

[0063] The alloy ingot obtained as described above is hot-extruded at 400–560°C, an extrusion ratio of 6–10:1, and an extrusion rate of 4–9 mm / min to obtain the rare earth silver-copper alloy. This is beneficial for obtaining a rare earth silver-copper alloy with higher strength.

[0064] In this invention, the extrusion ratio refers to the ratio of the cross-sectional area of ​​the extrusion cylinder cavity to the total cross-sectional area of ​​the extruded product, also known as the extrusion coefficient. The extrusion ratio is a parameter used in extrusion production to represent the amount of metal deformation.

[0065] In this invention, the hot extrusion temperature can be 400–560°C, preferably 430–540°C, and more preferably 450–520°C. The extrusion ratio can be 6–10:1, preferably 7–9:1, and more preferably 8–9:1. The extrusion rate can be 4–9 mm / min, preferably 5–8 mm / min, and more preferably 6–7 mm / min. Controlling the above parameters within the above ranges is more conducive to obtaining rare earth silver-copper alloys with better mechanical properties.

[0066] The rare earth silver alloy obtained by hot extrusion is in the form of bars with a diameter of 12-15 mm, preferably 13-14 mm.

[0067] According to a specific embodiment of the present invention, the preparation method of the rare earth silver-copper alloy of the present invention includes the following steps:

[0068] 1) Prepare raw materials pure silver, pure copper, lanthanum and cerium according to the composition of the rare earth silver-copper alloy; wherein, lanthanum is derived from elemental lanthanum metal or lanthanum-cerium metal, and cerium is derived from elemental cerium metal or lanthanum-cerium metal.

[0069] 2) Preheat pure silver, pure copper, lanthanum and cerium at 180-250℃ respectively, and set aside; melt the preheated pure silver and pure copper at 820-970℃ and remove the surface slag to obtain the initial melt;

[0070] 3) Add lanthanum and cerium to the initial melt, then heat to 860-1050℃ and hold at 860-1050℃ for 30-65 minutes to obtain the final melt; cast the final melt into a casting mold preheated to 250-350℃ to obtain an alloy ingot.

[0071] 4) The alloy ingot obtained in step 3) is hot-extruded at 400–560°C, with an extrusion ratio of 7–9:1 and an extrusion rate of 6–8 mm / min to obtain the rare earth silver-copper alloy. This is beneficial for obtaining a rare earth silver-copper alloy with better mechanical properties.

[0072] <Application>

[0073] This invention also provides the use of lanthanum and cerium in improving the mechanical properties of silver-copper alloys. Lanthanum and cerium are present in quantities of 0.2–3 parts by weight, and the silver-copper alloy comprises 97–99.8 parts by weight. In the lanthanum and cerium, the weight ratio of La to Ce is 1:1–3. In the 97–99.8 parts by weight silver-copper alloy, Cu comprises 3–25 parts by weight, with the balance being Ag and unavoidable impurities. The lanthanum is derived from elemental lanthanum or lanthanum-cerium metal, and the cerium is derived from elemental cerium or lanthanum-cerium metal. The preparation method is as described above and will not be repeated here.

[0074] The present invention particularly provides the use of lanthanum and cerium in improving the tensile strength, yield strength and elongation of silver-copper alloys.

[0075] The testing method is described below:

[0076] SEM testing: Tested using a German Zeiss-SIGMA500 cold field emission scanning electron microscope.

[0077] XRD testing: The test was conducted using a Panaco X-pertpowder X-ray diffractometer from the Netherlands.

[0078] Tensile strength, yield strength and elongation tests: The Instron 5982 universal testing machine was used to test the tensile strength, yield strength and elongation of metallic materials according to GB / T228.1-2021.

[0079] Example 1

[0080] In this embodiment, the rare earth silver-copper alloy has the following composition: Cu is 7 parts by weight, LaCe is 0.4 parts by weight (wherein the weight ratio of La to Ce is 1:2), and the balance is Ag and unavoidable impurities.

[0081] The preparation method of this rare earth silver-copper alloy is as follows:

[0082] 1) Prepare raw materials, namely pure silver ingots, pure copper ingots, and lanthanum-cerium metal, according to the composition of the rare earth silver-copper alloy. Dry and preheat the above raw materials at 200℃ for 1 hour, and set aside for later use.

[0083] 2) Place the preheated pure silver ingots and pure copper ingots into a graphite crucible, place the graphite crucible in a resistance furnace, and heat it to 950°C to completely melt the pure silver ingots and pure copper ingots, remove the surface slag, and obtain the initial melt.

[0084] 3) Add preheated lanthanum and cerium metal to the initial melt, then heat to 980°C and stir until the lanthanum and cerium metal are completely dissolved. Then hold at 980°C for 60 minutes to obtain the final melt. Pour the final melt into a casting mold preheated to 300°C and allow it to cool naturally to obtain an alloy ingot.

[0085] 4) The alloy ingot obtained in step 3) is hot extruded at 500°C, with an extrusion ratio of 8:1 and an extrusion rate of 6 mm / min to obtain a rare earth silver-copper alloy.

[0086] The rare earth silver-copper alloy obtained in this embodiment can be denoted as Ag / 7Cu / 0.4(La-Ce), where La:Ce = 1:2.

[0087] Example 2

[0088] In this embodiment, the rare earth silver-copper alloy has the following composition: Cu is 7 parts by weight, La is 0.12 parts by weight, Ce is 0.22 parts by weight, and the balance is Ag and unavoidable impurities.

[0089] The preparation method of this rare earth silver-copper alloy is as follows:

[0090] 1) Prepare raw materials, namely pure silver ingots, pure copper ingots, lanthanum elemental metal, and cerium elemental metal, according to the composition of the rare earth silver-copper alloy. Dry and preheat the above raw materials at 200℃ for 1 hour, and set aside for later use.

[0091] 2) Place the preheated pure silver ingots and pure copper ingots into a graphite crucible, place the graphite crucible in a resistance furnace, and heat it to 850°C to completely melt the pure silver ingots and pure copper ingots, remove the surface slag, and obtain the initial melt.

[0092] 3) Add preheated lanthanum and cerium metals to the initial melt, then heat to 950℃ and stir until all the lanthanum and cerium metals are dissolved. Then hold at 950℃ for 60 minutes to obtain the final melt. Pour the final melt into a casting mold preheated to 300℃ and allow it to cool naturally to obtain an alloy ingot.

[0093] 4) The alloy ingot obtained in step 3) is hot extruded at 450°C, with an extrusion ratio of 8:1 and an extrusion rate of 6 mm / min to obtain a rare earth silver-copper alloy.

[0094] The rare earth silver-copper alloy obtained in this embodiment can be denoted as Ag / 7Cu / 0.12La / 0.22Ce.

[0095] Comparative Example 1

[0096] In this comparative example, the alloy does not contain rare earth elements. The silver-copper alloy has the following composition: 7 parts by weight of Cu, with the balance being Ag and unavoidable impurities.

[0097] The preparation method of this silver-copper alloy is as follows:

[0098] 1) Prepare raw materials, pure silver ingots and pure copper ingots, according to the composition of the silver-copper alloy. Dry and preheat the above raw materials at 200℃ for 1 hour, and set aside for later use.

[0099] 2) Place the preheated pure silver ingots and pure copper ingots into a graphite crucible, place the graphite crucible in a resistance furnace, and heat it to 950°C to completely melt the pure silver ingots and pure copper ingots, remove the surface slag, and obtain the initial melt.

[0100] 3) Then heat to 980℃ and hold the initial melt at 980℃ for 60 minutes to obtain the final melt. Pour the final melt into a casting mold preheated to 300℃ and allow it to cool naturally to obtain an alloy ingot.

[0101] 4) The alloy ingot obtained in step 3) is hot extruded at 500°C, with an extrusion ratio of 8:1 and an extrusion rate of 6 mm / min to obtain a silver-copper alloy.

[0102] The silver-copper alloy obtained in this comparative example can be denoted as Ag / 7Cu.

[0103] Comparative Example 2

[0104] In this comparative example, the rare earth silver-copper alloy has the following composition: Cu is 2 parts by weight, La is 1.5 parts by weight, Ce is 0.8 parts by weight, and the balance is Ag and unavoidable impurities.

[0105] The preparation method of this rare earth silver-copper alloy is the same as in Example 1. The rare earth silver-copper alloy obtained in this comparative example can be denoted as Ag / 2Cu / 1.5La / 0.8Ce.

[0106] Comparative Example 3

[0107] In this comparative example, the rare earth silver-copper alloy has the following composition: Cu is 8.06 parts by weight, LaCe is 8.66 parts by weight (wherein the weight ratio of La to Ce is 3.23:5.43), and the balance is Ag and unavoidable impurities.

[0108] The preparation method of this rare earth silver-copper alloy is the same as in Example 1. The rare earth silver-copper alloy obtained in this comparative example can be denoted as Ag / 8.06Cu / 3.23La / 5.43Ce.

[0109] Experimental Example

[0110] (I) The SEM results of the extruded rare earth silver-copper alloy obtained in Example 1 at low and high magnification are shown in Figure 1(a) and Figure 1(b), respectively, and the XRD results are shown in Figure 1(b). Figure 2 As shown in Figures 1(a) and 1(b), a large number of fine, dispersed precipitates are distributed in the silver matrix, playing a role in precipitation strengthening. Figure 2 It can be seen that a second phase of β-Cu also exists in the alloy structure.

[0111] (II) The test results of tensile strength, yield strength and elongation of rare earth silver-copper alloys obtained in Examples 1, 2, 2, and 3, and silver-copper alloy of Comparative Example 1 are shown in Table 1.

[0112] Table 1

[0113]

[0114] Comparing Example 1 with Comparative Example 1, it can be seen that the addition of specific amounts of lanthanum and cerium in this invention is beneficial to improving the tensile strength, yield strength, and elongation of the resulting alloy. Comparing Example 1 with Comparative Example 3, it can be seen that increasing the amounts of copper, lanthanum, and cerium results in a more significant decrease in elongation. Comparing Example 2 with Comparative Example 2, it can be seen that increasing the ratio between the amounts of lanthanum and cerium results in a more significant decrease in tensile strength. Comparing Example 1 with Comparative Examples 1, 2, and 3, it can be seen that the rare-earth silver-copper alloy with a specific composition of this invention exhibits better mechanical properties.

[0115] This invention is not limited to the above-described embodiments. Any modifications, improvements, or substitutions that can be conceived by those skilled in the art without departing from the essential content of this invention fall within the scope of this invention.

Claims

1. A rare earth silver-copper alloy, characterized in that, It has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 3 to 25 parts by weight, LaCe is 0.2 to 3 parts by weight, and the balance is Ag and unavoidable impurities; The weight ratio of La to Ce is 1:1 to 3.

2. The rare earth silver-copper alloy according to claim 1, characterized in that, The rare earth silver-copper alloy has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 5 to 20 parts by weight, LaCe is 0.2 to 2 parts by weight, and the balance is Ag and unavoidable impurities. The weight ratio of La to Ce is 1:1 to 3.

3. The rare earth silver-copper alloy according to claim 1, characterized in that, The rare earth silver-copper alloy has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 5 to 15 parts by weight, LaCe is 0.2 to 1.5 parts by weight, and the balance is Ag and unavoidable impurities. The weight ratio of La to Ce is 1:1 to 3.

4. The rare earth silver-copper alloy according to claim 1, characterized in that, The rare earth silver-copper alloy has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 5 to 12 parts by weight, LaCe is 0.2 to 1 part by weight, and the balance is Ag and unavoidable impurities. The weight ratio of La to Ce is 1:1 to 3.

5. The rare earth silver-copper alloy according to claim 1, characterized in that, The rare earth silver-copper alloy has the following composition: based on 100 parts by weight of rare earth silver-copper alloy, Cu is 6 to 10 parts by weight, LaCe is 0.3 to 0.8 parts by weight, and the balance is Ag and unavoidable impurities; The weight ratio of La to Ce is 1:1 to 2.

6. The method for preparing the rare earth silver-copper alloy according to any one of claims 1 to 5, characterized in that, Includes the following steps: 1) Prepare raw materials pure silver, pure copper, lanthanum and cerium according to the composition of the rare earth silver-copper alloy; wherein, lanthanum is derived from elemental lanthanum metal or lanthanum-cerium metal, and cerium is derived from elemental cerium metal or lanthanum-cerium metal. 2) Melt pure silver and pure copper at 820-970℃ and remove surface slag to obtain the initial melt; 3) Add lanthanum and cerium to the initial melt, then heat to 860-1050℃ and hold at 860-1050℃ for 30-65 minutes to obtain the final melt; cast the final melt to obtain an alloy ingot. 4) The alloy ingot obtained in step 3) is hot-extruded at 400-560°C, with an extrusion ratio of 6-10:1 and an extrusion rate of 4-9 mm / min to obtain the rare earth silver-copper alloy.

7. The preparation method according to claim 6, characterized in that, Between step 1) and step 2), the following step is also included: preheating pure silver, pure copper, lanthanum and cerium at 180-250℃ for 30-80 minutes to obtain preheated pure silver, pure copper, lanthanum and cerium.

8. The preparation method according to claim 7, characterized in that, In step 2), the preheated pure silver and pure copper are placed into a graphite crucible, which is then placed into a resistance furnace to melt the pure silver and pure copper, thus obtaining the initial melt.

9. The preparation method according to claim 6, characterized in that: In step 3), before casting the final melt, the casting mold is preheated to 250-350°C. In step 4), the extrusion ratio is 7 to 9:1 and the extrusion rate is 5 to 8 mm / min.

10. Uses of lanthanum and cerium in improving the mechanical properties of silver-copper alloys.

Images