WO2013000147A1

WO2013000147A1 - Copper-chromium contactor and manufacturing method thereof

Info

Publication number: WO2013000147A1
Application number: PCT/CN2011/076642
Authority: WO
Inventors: 邱安宁; 帕拉萨R.S.; 严有为; 薛丽红; 史昆玉; 沈涛; 陈春浩
Original assignee: 阿尔斯通电网公司
Priority date: 2011-06-30
Filing date: 2011-06-30
Publication date: 2013-01-03

Abstract

A manufacturing method of copper-chromium (Cu-Cr) contactor comprises: mixing Cu powder and Cr powder at a predetermined ratio, milling the mixed powder to obtain composite powder with an average diameter between 10 nm and 200μm, and spark plasma sintering the composite powder. The Cu-Cr contactor produced by the method can be molded by one-step process, has fine and dispersive microstructure, and high density. The method is simple.

Description

铜铬触头及其制备方法发明领域 Copper-chromium contact and preparation method thereof

本发明涉及合金材料的制备技术，尤其涉及一种新颖的铜铬触头及其制备方法。 . 背景技术 The present invention relates to a technique for preparing an alloy material, and more particularly to a novel copper-chromium contact and a method of preparing the same. . Background technique

通常，在真空灭弧室中，利用真空中电弧的扩散性在高真空下使电流断路的真空灭弧室的触点都由相对的固定和可动的两个触头构成。目前， Cu-Cr合金是一种性能较佳的触头材料。在现有技术中， Cu-Cr合金触头材料的制备方法主要有：熔渗法、粉末烧结法、电弧熔炼法和快速凝固法。 Generally, in a vacuum interrupter, the contacts of the vacuum interrupter that break the current under high vacuum by utilizing the diffusivity of the arc in a vacuum are composed of two fixed and movable contacts. At present, Cu-Cr alloy is a better contact material. In the prior art, the preparation methods of the Cu-Cr alloy contact material mainly include: infiltration method, powder sintering method, arc melting method and rapid solidification method.

这些方法的主要特点是： The main features of these methods are:

1.熔渗法是将 Cu粉末和 Cr粉末混合，预制烧结成骨架结构，然后浸入熔融的 Cu中使 Cu充分浸渗至获得 Cr-Cr合金触头材料。本方法合金的成分容易控制，可以得到高致密度的产品，整个烧结熔渗过程需时约 3小时。本方法制备的触头机械强度较高，抗电蚀能力强。 1. The infiltration method is a method in which a Cu powder and a Cr powder are mixed, prefabricated into a skeleton structure, and then immersed in molten Cu to sufficiently impregnate Cu to obtain a Cr-Cr alloy contact material. The composition of the alloy of the method is easy to control, and a highly dense product can be obtained, and the entire sintering infiltration process takes about 3 hours. The contact prepared by the method has high mechanical strength and strong anti-corrosion ability.

2.粉末烧结法是将 Cu粉末和 Cr粉末混合，压制成形，然后烧结。本方法能保持 Cr颗粒的原始质点和 Cu的高导电、导热性 2. The powder sintering method is a method of mixing Cu powder and Cr powder, press forming, and then sintering. The method can maintain the original particle of Cr particles and the high conductivity and thermal conductivity of Cu.

3.电弧熔炼法是将 Cu粉末和 Cr粉末混合，等静压成棒坯，烧结电极，然后该电极在直流电弧下熔化，在水冷铜模中形成铸锭。本方法制造的 Cu-Cr合金性能优异， '具有机械强度好、 Cr颗粒细小、各相分布均匀等优点。 3. The arc melting method is a method in which Cu powder and Cr powder are mixed, isostatically pressed into a billet, and an electrode is sintered, and then the electrode is melted under a direct current arc to form an ingot in a water-cooled copper mold. The Cu-Cr alloy produced by the method has excellent properties, and has the advantages of good mechanical strength, fine Cr particles, and uniform distribution of phases.

4.快速凝固法快速凝固法主要包括旋转急冷法、雾化法和喷射成型法。快速凝固法可以有效地细化合金材料的晶粒度，因此可制备细晶、超细晶 Cu-Cr系合金材料。发明概述 4. Rapid solidification method The rapid solidification method mainly includes rotary quenching method, atomization method and injection molding method. The rapid solidification method can effectively refine the grain size of the alloy material, so that fine-grained, ultra-fine-grained Cu-Cr alloy materials can be prepared. Summary of invention

上述现有技术各有不足之处： The above prior art has its own shortcomings:

1熔渗法 1 infiltration method

该方法的缺点是生产效率低，成本高，易产生闭孔等熔渗缺陷，只能制备 Cu The disadvantage of this method is that the production efficiency is low, the cost is high, and infiltration defects such as closed cells are easily generated, and only Cu can be prepared.

- 1 - 替换（细则 26 质量分数 5%~50%的 Cu-Cr合金。 - 1 - replacement (rule 26 A Cu-Cr alloy with a mass fraction of 5% to 50%.

2.粉末烧结法 2. Powder sintering method

该方法的缺点是产品的空隙率较高，制得的合金韧性不高。材料的组织均匀性较低，只适合于制备 Cr含量低的 Cu-Cr合金。 The disadvantage of this method is that the void ratio of the product is high and the toughness of the obtained alloy is not high. The material has low structural uniformity and is only suitable for the preparation of Cu-Cr alloys with low Cr content.

3.电弧熔炼法 3. Arc melting method

该方法的缺点是工艺成本较高，设备投入大，生产周期延长，且电孤控制等工艺参数较复杂，不适合大规模生产。 The disadvantages of this method are high process cost, large equipment investment, prolonged production cycle, and complicated process parameters such as electric isolation control, which are not suitable for large-scale production.

4.快速凝固法 · 4. Rapid solidification method ·

该方法的缺点是成本较高，控制复杂。 The disadvantage of this method is that the cost is high and the control is complicated.

此外，以上各种方法制备的材料显微组织一般都在微米尺度，并未达到纳米尺度。 In addition, the microstructures of the materials prepared by the above various methods are generally on the micrometer scale and have not reached the nanometer scale.

因此，业界亟需一种新颖的铜铬触头制备方法，以克服上述现有技术的方法的不足。 Therefore, there is a need in the art for a novel copper-chromium contact fabrication method that overcomes the deficiencies of the prior art methods described above.

针对现有技术的上述不足，本发明的发明人经研究，提出了一种新颖的铜铬触头及其制备方法。本发明旨在至少解决以下 3个问题：（1 )触头材料制备，由于 Cu和 Cr不互溶，液相合金凝固时， Cr有共晶化的倾向，且由于 Cr与 Cu密度的差别，在熔炼时更容易造成成分偏析。普通的熔炼方法难以制备高 Cr含量且成分均匀的 Cu-Cr合金；（ 2 )均匀细小的显微结构，当合金中的 Cr发生宏观偏析时，触头的耐压强度等技术指标将急剧恶化。另外通过细化 Cr晶粒尺寸可以改善 Cu-Cr 触头材料的性能。此外， Cu-Cr合金的致密度（孔隙度）也是影响 Cu-Cr触头材料性能的关键因素之一。因此，如何制备组织分布均匀，具有细小的晶粒尺寸且致密度较高的 Cu-Cr合金材料是开发高性能 Cu-Cr合金触头材料要解决的主要问题之一；（3 )制备工艺，在解决上述两个问题后，材料的制备工艺还应尽量简单。因此开发成本低、能耗低、时间短的制备方法是研究 Cu-Cr合金触头材料要解决的另一个技术问题。 In view of the above deficiencies of the prior art, the inventors of the present invention have developed a novel copper-chromium contact and a preparation method thereof. The present invention aims to solve at least the following three problems: (1) Preparation of contact materials, since Cu and Cr are mutually miscible, Cr has a tendency to co-crystallize when solidified, and due to the difference in density between Cr and Cu, Segregation is more likely to occur during smelting. Ordinary smelting method is difficult to prepare Cu-Cr alloy with high Cr content and uniform composition; (2) Uniform and fine microstructure, when the Cr in the alloy is macrosegregated, the technical indexes such as the compressive strength of the contact will deteriorate sharply. . In addition, the performance of the Cu-Cr contact material can be improved by refining the Cr grain size. In addition, the density (porosity) of the Cu-Cr alloy is also one of the key factors affecting the properties of the Cu-Cr contact material. Therefore, how to prepare Cu-Cr alloy material with uniform microstructure distribution and fine grain size and high density is one of the main problems to be solved in developing high-performance Cu-Cr alloy contact materials; (3) Preparation process, After solving the above two problems, the preparation process of the material should be as simple as possible. Therefore, the preparation method with low development cost, low energy consumption and short time is another technical problem to be solved in the study of Cu-Cr alloy contact materials.

具体地，根据本发明的一个方面，提供了一种铜铬合金的制备方法，包括：将预设比例的铜粉末和铬粉末进行混合；对混合后的粉末进行研磨，以获得平均粒径在 10纳米到 200微米之间的复合粉末；以及对所述复合粉末进行放电等离子体烧结。 Specifically, according to an aspect of the invention, a method for preparing a copper-chromium alloy is provided, comprising: mixing a predetermined proportion of copper powder and chromium powder; and grinding the mixed powder to obtain an average particle diameter at a composite powder between 10 nanometers and 200 micrometers; and a discharge plasma of the composite powder Sintering.

根据一个较佳实施例，在上述的制备方法中，在所述将预设比例的铜和铬的粉末混合的步骤进一步包括：添加辅助粉末，所述辅助粉末的元素是 Zr、 Bi、 W 、 Ni、 Fe、 Nb和 V中的一种或多种。 According to a preferred embodiment, in the above preparation method, the step of mixing the powder of copper and chromium in a predetermined ratio further comprises: adding an auxiliary powder, the elements of the auxiliary powder being Zr, Bi, W, One or more of Ni, Fe, Nb, and V.

根据一个较佳实施例，在上述的制备方法中，所述研磨为高能球磨。 According to a preferred embodiment, in the above preparation method, the grinding is a high energy ball milling.

根据一个较佳实施例，在上述的制备方法中，在所述研磨步骤之后且在所述放电等离子体烧结步骤之前，该制备方法进一步包括：对所述复合粉末进行烘干的步骤。 According to a preferred embodiment, in the above preparation method, after the grinding step and before the discharge plasma sintering step, the preparation method further comprises the step of drying the composite powder.

根据一个较佳实施例，在上述的制备方法中，所述高能球磨的步骤进一步包括：将所述混合后的粉末连同球磨介质一起加入球磨容器；对所述球磨容器抽真空；在所述球磨容器中加入保护气体；以及将所述球磨容器置于球磨机上进行高能球磨。 ' According to a preferred embodiment, in the above preparation method, the step of high energy ball milling further comprises: adding the mixed powder to a ball mill vessel together with a ball milling medium; vacuuming the ball mill vessel; A protective gas is added to the vessel; and the ball mill vessel is placed on a ball mill for high energy ball milling. '

根据一个较佳实施例，在上述的制备方法中，所述保护气体为高纯氩气。根据一个较佳实施例，在上述的制备方法中，所述球磨介质为 1%~15.5%盾量比的无水乙醇或***。 According to a preferred embodiment, in the above preparation method, the shielding gas is high purity argon. According to a preferred embodiment, in the above preparation method, the ball milling medium is anhydrous ethanol or diethyl ether in a ratio of 1% to 15.5% by weight.

根据一个较佳实施例，在上述的制备方法中，所述球磨机的转速为 100~400rpm。 According to a preferred embodiment, in the above preparation method, the rotation speed of the ball mill is 100 to 400 rpm.

根据一个较佳实施例，在上述的制备方法中，所述高能球磨步骤的时间小于等于 150小时。 According to a preferred embodiment, in the above preparation method, the high energy ball milling step has a time of less than or equal to 150 hours.

根据一个较佳实施例，在上述的制备方法中，所述放电等离子体烧结的烧结环境为真空或保护气体。 According to a preferred embodiment, in the above preparation method, the sintering environment in which the discharge plasma is sintered is a vacuum or a shielding gas.

根据一个较佳实施例，在上述的制备方法中，烧结温度为 600~1000°C。 According to a preferred embodiment, in the above preparation method, the sintering temperature is 600 to 1000 °C.

根据一个较佳实施例，在上述的制备方法中，所述放电等离子体烧结的烧结环境为压力为 30〜100MPa。 According to a preferred embodiment, in the above preparation method, the sintering environment in which the discharge plasma is sintered is a pressure of 30 to 100 MPa.

根据一个较佳实施例，在上述的制备方法中，烧结温度的升温速度为 50~350 According to a preferred embodiment, in the above preparation method, the sintering temperature is increased by 50 to 350.

°C/分钟，保温时间为 1~10分钟。 °C / minute, holding time is 1~10 minutes.

根据一个较佳实施例，在上述的制备方法中，在所述预设比例中，铬的质量比为 5 % ~ 75 %。此外，根据本发明的另一方面，还提供了一种通过以上所述的制备方法制得的铜铬触头，应用于真空灭弧室。 According to a preferred embodiment, in the above preparation method, the mass ratio of chromium in the predetermined ratio is 5% to 75%. Further, according to another aspect of the present invention, there is also provided a copper-chromium contact produced by the above-described preparation method, which is applied to a vacuum interrupter.

综上所述，利用本发明制备的铜铬触头，可以一次成型，而且材料具有细小弥散的显微组织，致密度高，制备工艺简单可广泛应用于真空灭弧室等领域。 In summary, the copper-chromium contact prepared by the invention can be formed at one time, and the material has a fine dispersed microstructure, high density, simple preparation process and can be widely applied in the fields of vacuum interrupter.

应当理解，本发明以上的一般性描述和以下的详细描述都是示例性和说明性的，并且旨在为如权利要求所述的本发明提供进一步的解释。附图说明 The foregoing description of the preferred embodiments of the invention, DRAWINGS

附图示出了本发明的实施例。附图中： The drawings illustrate embodiments of the invention. In the figure:

图 1示出了根据本发明的铜铬触头的制备方法的基本步骤的流程图。 BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a flow chart showing the basic steps of a method of preparing a copper-chromium contact according to the present invention.

图 2进一步示出了图 1中的高能球磨步骤的基本步骤的流程。 Figure 2 further illustrates the flow of the basic steps of the high energy ball milling step of Figure 1.

为了增加本发明的可理解性，附上参考资料。该参考资料揭示了显微组织图像，结合参考资料能够使得本发明更加易于理解。 In order to increase the intelligibility of the present invention, reference materials are attached. This reference discloses a microstructure image which, in conjunction with reference materials, can make the invention easier to understand.

图 3a和图 3b分别为 1000倍和 10000倍的高能球磨 Cu-Cr纳米粉末显微组织。图 4a和图 4b分别为 1000倍和 10000倍的放电等离子体烧结的 Cu-Cr纳米触头材料显微组织。 Figures 3a and 3b show the microstructures of high-energy ball-milled Cu-Cr nanopowders at 1000 and 10,000, respectively. Figures 4a and 4b show the microstructures of Cu-Cr nanocontact materials sintered by discharge plasma at 1000 times and 10000 times, respectively.

图 5a为放大 100000倍的 CuCr25放电等离子体烧结的 Cu-Cr纳米触头材料显微组织。 - 图 5b为 CuCr50的放电等离子体烧结的 Cu-Cr纳米触头材料显微组织。发明的详细说明 Figure 5a shows the magnified microstructure of Cu-Cr nanocontact material sintered by CuCr25 discharge plasma at 100,000 times magnification. - Figure 5b shows the microstructure of Cu-Cr nanocontact material sintered by plasma discharge of CuCr50. Detailed description of the invention

现在将详细参考附图描述本发明的实施例。 Embodiments of the present invention will now be described in detail with reference to the drawings.

图 1示出了根据本发明的铜铬触头的制备方法 100的基本步骤。如图 1所示，该制备方法 100主要包括以下几个步骤： Figure 1 shows the basic steps of a method 100 of preparing a copper-chromium contact in accordance with the present invention. As shown in FIG. 1, the preparation method 100 mainly includes the following steps:

步骤 102: 将预设比例的铜粉末和铬粉末进行混合； Step 102: mixing a preset proportion of copper powder and chromium powder;

步骤 104: 对混合后的粉末进行研磨，以获得平均粒径在- 10纳米到 200微米之间的复合粉末； Step 104: grinding the mixed powder to obtain a composite powder having an average particle diameter of between 10 nm and 200 μm;

步骤 106：对复合粉末进行放电等离子体烧结。在上述步骤 102中，预设比例优选为 Cr的质量比为 5%~75%。此外，如必要，也可添加一些微量的辅助粉末，该辅助粉末的元素可以是 Zr、 Bi、 W、 Ni、 Fe、 Nb和 V中的一种或多种。特别是，例如， Zr、 Ni、 Fe等辅助粉末可以辅助提高成品的致密度，也能改善工艺性能。例如， Bi、 W等辅助粉末可以改善熔焊性能。例如， Nb等辅助粉末可以改善耐压和开断性能。此外，在所述研磨步骤 104之后且在所述放电等离子体烧结步骤 106之前，本发明的制备方法 100可以进一步包括：对复合粉末进行烘干的步骤。该烘干优选是在真空环境或者惰性气体保护的环境下进行的。当然，本领域的技术人员可以理解，该烘千步骤并非是本发明的一必需的步骤。换言之，本发明可以对未经烘干的复合粉末进行放电等离子体烧结，并同样获得本发明的大部分技术效果。 Step 106: Perform discharge plasma sintering on the composite powder. In the above step 102, the preset ratio is preferably a mass ratio of Cr of 5% to 75%. Further, if necessary, some trace amount of auxiliary powder may be added, and the element of the auxiliary powder may be one or more of Zr, Bi, W, Ni, Fe, Nb, and V. In particular, for example, auxiliary powders such as Zr, Ni, Fe, etc. can assist in improving the density of the finished product and also improving the process performance. For example, auxiliary powders such as Bi and W can improve the weldability. For example, an auxiliary powder such as Nb can improve withstand voltage and breaking properties. Further, after the grinding step 104 and before the discharge plasma sintering step 106, the preparation method 100 of the present invention may further comprise the step of drying the composite powder. The drying is preferably carried out in a vacuum environment or an inert gas atmosphere. Of course, those skilled in the art will appreciate that the drying step is not an essential step of the present invention. In other words, the present invention can perform discharge plasma sintering on the unbaked composite powder, and also obtains most of the technical effects of the present invention.

传统的烧结设备烧结温度高、烧结时间长，很难保证材料同时实现完全致密化和晶粒细小。因此，本发明采用的放电等离子体烧结（SPS )的烧结方式，该烧结方式可以有效地阻止烧结块体晶粒长大，同时达到密度要求。使用 SPS方法，工艺简单，升温速度可控，烧结时间短，冷却速度快，外加压力和烧结气氛可控等特点，能够获得致密度高、组织细小的高性能材料。根据一个优选的实施例，步骤 108中的放电等离子体烧结的工艺参数优选为：烧结环境为真空或保护气氛，烧结温度为 600 1000 °C , 压力为 30~100MPa，升温速度为 50〜350°C/分钟，保温时间为 1-10分钟。可以理解，上述各加工参数和条件也可以根据实际应用之需要而被单独或个别組合地采用。 Conventional sintering equipment has a high sintering temperature and a long sintering time, and it is difficult to ensure that the material is simultaneously fully densified and fine. Therefore, the spark plasma sintering (SPS) sintering method employed in the present invention can effectively prevent grain growth of the sintered bulk while achieving density requirements. Using the SPS method, the process is simple, the heating rate is controllable, the sintering time is short, the cooling rate is fast, the applied pressure and the sintering atmosphere are controllable, and high-performance materials with high density and fine structure can be obtained. According to a preferred embodiment, the process parameters of the spark plasma sintering in step 108 are preferably: the sintering environment is a vacuum or a protective atmosphere, the sintering temperature is 600 1000 ° C, the pressure is 30-100 MPa, and the heating rate is 50-350 °. C / minute, holding time is 1-10 minutes. It will be understood that the various processing parameters and conditions described above may also be employed individually or in combination according to the needs of the actual application.

特别地，根据本发明，上述步骤 104 中的研磨优选为高能球磨。通过在高能球磨机中进行长时间研磨，使混合后的粉末在频繁的碰撞过程中发生强烈的塑性形变和冷焊，这些粉末又因加工硬化而发生碎裂，碎裂后粉末露出的新鲜原子表面又极易发生焊合，如此不断重复的冷焊、碎裂、再焊合过程，使其组织结构不断细化，最终达到原子级混合，实现合金化的目的。本发明中，通过控制不同的球磨工艺参数即可得到不同粒径分布（ 10纳米到 200微米）的复合粉末。 Particularly, according to the present invention, the grinding in the above step 104 is preferably a high energy ball milling. Through long-time grinding in a high-energy ball mill, the mixed powder undergoes strong plastic deformation and cold welding during frequent collisions. These powders are broken by work hardening, and the fresh atomic surface of the powder after chipping is exposed. It is also prone to soldering, such repeated repeated cold welding, chipping, re-welding process, so that its organizational structure is continuously refined, and finally achieve atomic mixing, to achieve alloying purposes. In the present invention, composite powders having different particle size distributions (10 nm to 200 μm) can be obtained by controlling different ball milling process parameters.

例如，如图 2所示，以上图 1所示的方法中的高能球磨的步驟 104可以进一步包括： For example, as shown in FIG. 2, the step 104 of high energy ball milling in the method illustrated in FIG. 1 above may further include:

步骤 202: 将混合后的粉末连同球磨介质一起加入球磨容器；步骤 204: 对球磨容器抽真空； Step 202: adding the mixed powder to the ball mill vessel together with the ball milling medium; Step 204: Vacuuming the ball mill container;

步骤 206: 在球磨容器中加入保护气体，例如高纯氩气；以及 Step 206: adding a shielding gas, such as high purity argon, to the ball mill vessel;

步骤 208: 将球磨容器置于球磨机（例如行星式球磨机）上进行高能球磨。根据本发明的一个优选实施例，上述的球磨介质优选为含量为 1%~15.5% (质量比）的无水乙醇或***，磨球可以采用直径为 6~10mm的不锈钢球或硬质合金球（如 WC-Co 球），球料比（质量比）优选为 10: 1〜30: 1，球磨机转速优选为 100~400rpm, 球磨时间优选为小于或等于 150 小时。可以理解，上述各加工参数和条件也可以居实际应用之需要而被单独或个别组合地采用。 Step 208: Place the ball mill vessel on a ball mill (eg, a planetary ball mill) for high energy ball milling. According to a preferred embodiment of the present invention, the ball milling medium is preferably anhydrous ethanol or diethyl ether in an amount of 1% to 15.5% by mass, and the grinding ball may be a stainless steel ball or a cemented carbide ball having a diameter of 6 to 10 mm. (e.g., WC-Co ball), the ball to material ratio (mass ratio) is preferably 10: 1 to 30: 1, the ball mill rotation speed is preferably 100 to 400 rpm, and the ball milling time is preferably 150 hours or less. It will be understood that the various processing parameters and conditions described above may also be employed individually or individually in combination for practical application.

此外，在放电等离子体烧结的步骤 106之前，可以先将中间粉末设置于一模具内，该模具可以根据真空灭弧室需要的铜铬触头的形状设计。这样，在上述步骤 106的放电等离子体烧结结束后就可以得到最终的铜铬触头，无需后续的力 p工或处理。示例 1 : Cu-Cr触头材料的制备 Further, prior to the step 106 of spark plasma sintering, the intermediate powder may be first placed in a mold which may be designed according to the shape of the copper-chromium contacts required for the vacuum interrupter. Thus, after the discharge plasma sintering of the above step 106 is completed, the final copper-chromium contact can be obtained without subsequent force or processing. Example 1 : Preparation of Cu-Cr contact material

根据本发明提供的方法，将盾量百分比为 50:50的 Cu粉和 Cr粉充分混合后，放入不锈钢球磨罐中，并加入直径为 10mm的硬质合金球，球料比（质量比）为 30: 1。此外，添加 15.5% (质量比）的无水乙醇作为球磨介质，装入南京大学仪器厂生产的 QM-BP型行星式球磨机中进行球磨。球磨时间分别为 60小时。在烘干后，将球磨得到的粉末进行放电等离子体烧结得到纳米级 Cu-Cr 合金触头材料。烧结温度设定为 900°C。粉末和烧结得到的块体材料显微组织见图 3和图 4。粉末和烧结得到的块体材料的显微组织显示：利用本发明提供的方法可制备成分分布均勾，晶粒尺寸达到纳米尺度的材料。示例 2： Cu-Cr纳米触头材料的制备 According to the method provided by the present invention, the Cu powder and the Cr powder having a shield percentage of 50:50 are thoroughly mixed, placed in a stainless steel ball mill jar, and a cemented carbide ball having a diameter of 10 mm is added, and the ratio of the ball to the mass (mass ratio) For 30: 1. In addition, 15.5% (by mass) of anhydrous ethanol was added as a ball milling medium, and it was placed in a QM-BP planetary ball mill manufactured by Nanjing University Instrument Factory for ball milling. The ball milling time was 60 hours. After drying, the ball milled powder was subjected to spark plasma sintering to obtain a nano-sized Cu-Cr alloy contact material. The sintering temperature was set to 900 °C. The microstructure of the bulk material obtained from the powder and sintering is shown in Figures 3 and 4. The microstructure of the bulk material obtained by powdering and sintering shows that a material having a uniform composition distribution and a nanometer size can be prepared by the method provided by the present invention. Example 2: Preparation of Cu-Cr nanocontact material

根据本发明提供的方法，分别将质量百分比为 50:50、 75:25和 90: 10的 Cu 粉和 Cr粉充分混合，放入不锈钢球磨罐中，并加入直径为 10mm的硬质合金球，球料比（质量比）为 30: 1。添加 15.5% Ϊ质量比）的无水乙醇作为球磨介质，装入南京大学仪器厂生产的 QM-BP型行星式球磨机中进行球磨。球磨 According to the method provided by the present invention, the Cu powder and the Cr powder having the mass percentages of 50:50, 75:25 and 90:10 are respectively thoroughly mixed, placed in a stainless steel ball mill jar, and a cemented carbide ball having a diameter of 10 mm is added. The ball to material ratio (mass ratio) is 30:1. Anhydrous ethanol containing 15.5% by mass of hydrazine was added as a ball milling medium to a QM-BP planetary ball mill manufactured by Nanjing University Instrument Factory for ball milling. Ball mill

- 6 - 细 2 时间分别为 100h。烧结温度为 900 °C。在烘干后，将球磨得到的粉末进行 SPS 烧结得到納米晶 Cu-Cr合金触头材料。粉末和烧结得到的块体材料显微组织见图 5。最终获得的材料的机械性能和物理性能如表 1所示。表 1 不同 Cu: Cr比例制备的材料的性能 - 6 - Fine 2 The time is 100h. The sintering temperature was 900 °C. After drying, the ball milled powder is subjected to SPS sintering to obtain a nanocrystalline Cu-Cr alloy contact material. The microstructure of the bulk material obtained from the powder and sintering is shown in Fig. 5. The mechanical properties and physical properties of the finally obtained materials are shown in Table 1. Table 1 Properties of materials prepared with different ratios of Cu:Cr

综上，本发明至少能实现以下的技术效果或优点：

In summary, the present invention can at least achieve the following technical effects or advantages:

1.合金成分控制简单，不需要高温熔炼，成分偏析少、分布均匀。 1. The alloy composition is simple to control, does not require high-temperature melting, and has less segregation of components and uniform distribution.

2.通过高能球磨可获得晶粒尺寸从纳米级别到微米级别的粉末，且尺度可控。 2. Powders with grain sizes ranging from nanometers to micrometers can be obtained by high energy ball milling with dimensional controllable.

3.SPS烧结时间短，晶粒来不及长大，仍能保持原来的尺度，可获得细小、均匀、致密度高的材料。工艺参数简单，生产效率较高。 3. The sintering time of SPS is short, the grain can not grow up, and the original scale can be maintained, and the material with small, uniform and high density can be obtained. The process parameters are simple and the production efficiency is high.

4.可根据触头的形状设计相应的模具， SPS 烧结后可一次成型，无需后续力口工。 4. The corresponding mold can be designed according to the shape of the contact. SPS can be molded once after sintering, without the need for follow-up force.

本领域技术人员可显见，可对本发明的上述示例性实施例进行各种修改和变型而不偏离本发明的精神和范围。因此，旨在使本发明覆盖落在所附权利要求书及其等效技术方案范围内的对本发明的修改和变型。 It will be apparent to those skilled in the art that various modifications and changes can be made in the above-described embodiments of the present invention without departing from the spirit and scope of the invention. Therefore, it is intended that the present invention cover the modifications and modifications of the invention

Claims

权利要求书 Claim

1. 一种铜铬合金的制备方法，其特征在于，包括： A method for preparing a copper-chromium alloy, comprising:

将预设比例的铜粉末和铬粉末进行混合； Mixing a predetermined proportion of copper powder and chromium powder;

对混合后的粉末进行研磨，以获得平均粒径在 10纳米到 200微米之间的复合粉末；以及 The mixed powder is ground to obtain a composite powder having an average particle diameter of between 10 nm and 200 μm;

对所述复合粉末进行放电等离子体烧结。 The composite powder was subjected to discharge plasma sintering.

2. 如权利要求 1所述的制备方法，其特征在于，在所述将预设比例的铜和铬的粉末混合的步骤进一步包括：添加辅助粉末，所述辅助粉末的元素是 Zr、 Bi、2. The preparation method according to claim 1, wherein the step of mixing the powder of the predetermined ratio of copper and chromium further comprises: adding an auxiliary powder, the elements of the auxiliary powder being Zr, Bi,

W 、 Ni、 Fe、 Nb和 V中的一种或多种。 One or more of W, Ni, Fe, Nb, and V.

3. 如权利要求 1所述的制备方法，其特征在于，所述研磨为高能球磨。 3. The production method according to claim 1, wherein the grinding is high energy ball milling.

4. 如权利要求 1所述的制备方法，其特征在于，在所述研磨步骤之后且在所述放电等离子体烧结步骤之前，该制备方法进一步包括：对所述复合粉末进行烘干的步骤。 The preparation method according to claim 1, wherein the preparation method further comprises: a step of drying the composite powder after the grinding step and before the discharge plasma sintering step.

5. 如权利要求 3所述的制备方法，其特征在于，所述高能球磨的步骤进一步包括： 5. The method according to claim 3, wherein the step of high energy ball milling further comprises:

将所述混合后的粉末连同球磨介质一起加入球磨容器； Adding the mixed powder together with a ball milling medium to a ball mill vessel;

对所述球磨容器抽真空； Vacuuming the ball mill vessel;

在所述球磨容器中加入保护气体；以及 Adding a shielding gas to the ball mill vessel;

将所述球磨容器置于球磨机上进行高能球磨。 The ball mill vessel is placed on a ball mill for high energy ball milling.

6. 如权利要求 5所述的制备方法，其特征在于，所述保护气体为高純氩气。 The method according to claim 5, wherein the shielding gas is high purity argon gas.

7. 如权利要求 5所述的制备方法，其特征在于，所述球磨介质为 1%~15.5% 质量比的无水乙醇或***。 The preparation method according to claim 5, wherein the ball milling medium is anhydrous ethanol or diethyl ether in a mass ratio of 1% to 15.5%.

8. 如权利要求 5 所述的制备方法，其特征在于，所述球磨机的转速为 100~400rpm。 The preparation method according to claim 5, wherein the ball mill has a rotation speed of 100 to 400 rpm.

9. 如权利要求 5所述的制备方法，其特征在于，所述高能球磨步骤的时间小于等于 150小时。 The preparation method according to claim 5, wherein the high-energy ball milling step has a time of less than or equal to 150 hours.

10. 如权利要求 1所述的制备方法，其特征在于，所述放电等离子体烧结的烧结环境为真空或保护气体。 The method according to claim 1, wherein the sintering environment in which the discharge plasma is sintered is a vacuum or a shielding gas.

11. 如权利要求 1所述的制备方法，其特征在于，烧结温度为 600 1000 °c。The method according to claim 1, wherein the sintering temperature is 600 1000 °c.

12. 如权利要求 1的制备方法，其特征在于，所述放电等离子体烧结的烧结环境为压力为 30~100MPa。 The method according to claim 1, wherein the sintering environment in which the discharge plasma is sintered has a pressure of 30 to 100 MPa.

13. 如权利要求 1的制备方法，其特征在于，烧结温度的升温速度为 50 350 °C/分钟，保温时间为 1~10分钟。 The method according to claim 1, wherein the sintering temperature is raised at a rate of 50 350 ° C / min and the holding time is 1 to 10 minutes.

14. 如权利要求 1所述的制备方法，其特征在于，在所述预设比例中，铬的质量比为 5 % ~ 75 %。 The method according to claim 1, wherein in the predetermined ratio, the mass ratio of chromium is 5 % to 75%.

15. 一种通过以上任一权利要求所述的制备方法制得的铜铬触头，应用于真空灭弧室。 A copper-chromium contact produced by the preparation method according to any of the preceding claims, applied to a vacuum interrupter.