Vacuum hot-pressing copper-based composite material preparation process

Abstract

The invention relates to the technical field of copper-based composite material preparation, and discloses a vacuum hot-pressing copper-based composite material preparation process which comprises the following steps: step 1, pre-treating tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder, adding the tungsten powder, the molybdenum powder, the chromium powder, the tin powder and the zinc powder into the copper powder, mixing and stirring to obtain a mixed material; then copper-based composite powder is prepared through vacuum ball milling; 2, the copper-based composite powder and pure copper powder are subjected to cold press molding; and thirdly, the copper-based composite material blank formed through cold pressing is loaded into a heat-resistant stainless steel 310S mold. The copper-based composite powder and the pure copper powder are subjected to cold press molding, the cold press molding pressure is small, the efficiency is high, the cold press molding method is suitable for batch production, the heat-resistant stainless steel 310S mold is arranged, so that a copper-based composite material blank can be conveniently loaded, and the heat-resistant stainless steel 310S mold is reasonable in structural design, suitable for batch hot pressing, high in production efficiency, low in cost, stable in quality and suitable for large-scale production. The method is suitable for batch production.

Description

Technical Field

[0001] The invention relates to the technical field of copper-based composite material preparation, and more specifically to a vacuum hot-pressing copper-based composite material preparation process. Background Art

[0002] The preparation technology of copper-based composite materials is a versatile, porous and highly customizable technology that can not only improve the performance of materials, but also enhance the wear resistance, corrosion resistance, electrical conductivity, heat transfer, etc. of materials. Therefore, it is widely used in metal manufacturing, electronic equipment, aerospace and other fields. The preparation methods of copper-based composite materials are generally divided into hot pressing, powder metallurgy and electrodeposition.

[0003] At present, hot pressing is a common method for preparing copper-based composite materials. Under the action of high temperature and high pressure, various materials are pressed together with copper powder to make them tightly combined to form a new material with multiple properties. However, when hot pressing copper-based composite materials, it is not convenient to cold press copper-based composite materials. When only pressing by high temperature and high pressure, the pressure is large and the production efficiency is low, which needs to be improved. Summary of the invention

[0004] In order to overcome the above-mentioned defects of the prior art, the present invention provides a vacuum hot-pressing copper-based composite material preparation process to solve the problems existing in the above-mentioned background technology.

[0005] The present invention provides the following technical solution: a vacuum hot-pressing copper-based composite material preparation process, comprising the following steps:

[0006] Step 1: pre-treat tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder, then add tungsten powder, molybdenum powder, chromium powder, tin powder and zinc powder to copper powder for mixing, and then vacuum ball mill to prepare copper-based composite powder;

[0007] Step 2: cold pressing the copper-based composite powder and the pure copper powder;

[0008] Step 3: Place the cold-pressed copper-based composite material blank into a heat-resistant stainless steel 310S mold;

[0009] Step 4: Place the heat-resistant stainless steel 310S mold containing the copper-based composite material blank into a vacuum hot pressing furnace, and after vacuuming - heating - heat preservation - taking out of the furnace, the one-time forming of the copper-based composite material is achieved.

[0010] Furthermore, in step one, the pretreatment method is to first screen the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder respectively, control the particles of the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder within a specific range, and then chemically etch, ultrasonically clean and dry the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder to eliminate oxides or impurities on the surface and inside of the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder.

[0011] Furthermore, in step 1, the mixing time of the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder is 40-50 minutes, and the stirring speed is 10-30r / min.

[0012] Furthermore, in step 1, the ball milling speed is 100-300 r / min, the ball milling time is 8 hours, the ball milling is performed for 30 minutes with a rest period of 15 minutes, and the pressure in the ball milling tank is 0-1P.

[0013] Furthermore, in step 2, the copper-based composite powder and the pure copper powder are cold pressed at a pressure of 500-700 MPa, and the density of the copper-based composite powder and the pure copper powder is 7.5-8.0 g / cm, and then the pressure is maintained for 15 seconds.

[0014] Furthermore, in step 2, the cold pressing mold comprises a female mold, an upper punch and a lower punch. During cold pressing, the lower punch is located below the inner cavity of the female mold, the upper punch is located above the inner cavity of the female mold, and the copper-based composite powder and the pure copper powder are located between the upper punch and the lower punch inside the female mold. The copper-based composite powder and the pure copper powder can be cold pressed into a copper-based composite material blank.

[0015] Furthermore, in step three, the heat-resistant stainless steel 310S mold includes a female mold and a punch, the female mold is located between two punches, and the copper-based composite material blank is located inside the female mold between the two punches.

[0016] Furthermore, in step 4, the vacuum hot pressing furnace is evacuated to 0.01 Pa, the heating temperature is 800-1050° C., the unit pressure is 50-100 MPa, and the insulation time is 60-180 min.

[0017] Furthermore, in step 4, after the copper-based composite material is fired, it needs to be post-processed such as burr removal and polishing to achieve the required surface quality.

[0018] Technical effects and advantages of the present invention:

[0019] 1. The present invention performs cold pressing on the copper-based composite powder and the pure copper powder. The cold pressing has low pressure and high efficiency, and is convenient for cold pressing the copper-based composite material, and is suitable for mass production.

[0020] 2. The present invention is convenient for loading copper-based composite material blanks by providing a heat-resistant stainless steel 310S mold. The heat-resistant stainless steel 310S mold has a reasonable structural design, is suitable for batch hot pressing, has high production efficiency, low cost, stable quality, and is suitable for batch production.

[0021] 3. The present invention pre-treats tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder to eliminate oxides or impurities on the surface and inside of tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder, thereby ensuring good quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a process flow chart of the vacuum hot-pressing copper-based composite material preparation process.

[0023] Figure 2 It is a schematic diagram of the structure of the copper-based composite material blank of the present invention.

[0024] Figure 3 It is a schematic diagram of the cold pressing mold structure of the present invention.

[0025] Figure 4 It is a schematic diagram of the heat-resistant stainless steel 310S mold structure of the present invention. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. In addition, the forms of the various structures described in the following embodiments are only examples. The vacuum hot-pressing copper-based composite material preparation process involved in the present invention is not limited to the various structures described in the following embodiments. All other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0027] Embodiment 1:

[0028] like Figure 1-4 As shown, a vacuum hot-pressing copper-based composite material preparation process comprises the following steps:

[0029] Step 1: pre-treat tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder, then add tungsten powder, molybdenum powder, chromium powder, tin powder and zinc powder to copper powder for mixing, and then vacuum ball mill to prepare copper-based composite powder;

[0030] Step 2: cold pressing the copper-based composite powder and the pure copper powder;

[0031] Step 3: Place the cold-pressed copper-based composite material blank into a heat-resistant stainless steel 310S mold;

[0032] Step 4: Put the heat-resistant stainless steel 310S mold containing the copper-based composite material blank into a vacuum hot pressing furnace, and through vacuuming - heating - heat preservation - out of the furnace, the copper-based composite material is formed in one go;

[0033] In step one, the pretreatment method is to first screen the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder respectively, control the particles of the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder within a specific range, and then chemically etch, ultrasonically clean and dry the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder to eliminate oxides or impurities on the surface and inside of the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder. In step one, the mixing and stirring time of tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder is 40-50min, the stirring speed is 10-30r / min, the ball milling speed in step one is 100-300r / min, the ball milling time is 8 hours, and the ball milling time is 15min after every 30min of operation. The pressure in the ball milling tank is 0-1P.

[0034] In this embodiment, oxides or impurities on the surface and inside of tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder can be eliminated by chemical etching, ultrasonic cleaning and drying, thereby ensuring the good quality of tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder. Then, through mixing, stirring and vacuum ball milling, copper powder is fully mixed with tungsten powder, molybdenum powder, chromium powder, tin powder and zinc powder to form a copper-based mixed powder, which is convenient for the subsequent cold pressing of copper-based composite powder and pure copper powder.

[0035] Embodiment 2:

[0036] like Figure 1-4 As shown, in step 2, the copper-based composite powder and the pure copper powder are cold pressed at a pressure of 500-700 MPa, and the density of the copper-based composite powder and the pure copper powder is 7.5-8.0 g / cm, and then the pressure is maintained for 15 seconds. In step 2, the cold pressing mold includes a female mold, an upper punch and a lower punch. During cold pressing, the lower punch is located below the inner cavity of the female mold, and the upper punch is located above the inner cavity of the female mold. The copper-based composite powder and the pure copper powder are located between the upper punch and the lower punch inside the female mold. The copper-based composite powder and the pure copper powder can be cold pressed into a copper-based composite material blank.

[0037] In this embodiment, the copper-based composite powder and pure copper powder are cold pressed into a copper-based composite material. During the cold pressing, the copper-based composite powder and the pure copper powder are located between the upper punch and the lower punch inside the female mold. The copper-based composite powder and the pure copper powder can be cold pressed into a copper-based composite material blank through the upper punch and the lower punch, which is convenient for subsequent mold installation and vacuum hot pressing.

[0038] Embodiment three:

[0039] like Figure 1-4As shown, in step three, the heat-resistant stainless steel 310S mold includes a female mold and a punch, the female mold is located between the two punches, and the copper-based composite material blank is located inside the female mold between the two punches. In step four, the vacuum hot pressing furnace is evacuated to 0.01pa, the heating temperature is 800-1050°C, the unit pressure is 50-100MP, and the insulation time is 60-180min. In step four, after the copper-based composite material is taken out of the furnace, it needs to be post-processed such as burr cleaning and polishing to achieve the required surface quality.

[0040] In this embodiment, the heat-resistant stainless steel 310S mold formed by the female mold, the upper punch and the lower punch is convenient for holding the copper-based composite material blank. The setting of the vacuum hot pressing furnace is convenient for hot pressing the copper-based composite material, so as to realize one-time forming of the copper-based composite material and achieve the required density, strength and mechanical properties. Through post-processing such as burr cleaning and polishing, the copper-based composite material can achieve the required surface quality.

[0041] In Example 1, the weight ratio of each raw material component is: tungsten powder is 19 to 20 parts, molybdenum powder is 15 to 18 parts, chromium powder is 21 to 25 parts, tin powder is 9 to 12 parts, zinc powder is 11 to 13 parts, and copper powder is 120 to 150 parts. Then, each raw material is screened in turn by a screening machine so that the particle size of each raw material is controlled within a specific range. During pretreatment, tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder are chemically etched, ultrasonically cleaned and dried respectively. Then, the pretreated tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder are stirred and mixed by a mixing device. The stirring speed of the mixing device is controlled at 10-30r / min, and the mixing is continued. The raw materials are mixed for 40-50 minutes to make them fully mixed and more evenly mixed. Then, tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder are discharged into the vacuum ball mill. The ball-to-material ratio is 0.9-1.1. The particle size of the grinding balls is divided into three sizes, with large-sized grinding balls accounting for 30%, medium-sized grinding balls accounting for 40%, and small-sized grinding balls accounting for 30%. The speed of three different particle size grinding balls is 100-300r / min, the ball milling time is 8 hours, and the interval is 15 minutes every 30 minutes. The tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder can be fully ground into smaller particles to improve the uniformity and formability of subsequent pressing.

[0042] In Example 2, the copper-based composite powder and the pure copper powder are placed between the upper punch and the lower punch inside the female mold, and a pressure of 500-700 MPa is applied by the upper punch and the lower punch to cold-press the copper-based composite powder and the pure copper powder. After the density of the copper-based composite powder and the pure copper powder is cold-pressed to 7.5-8.0 g / cm, the pressure is maintained for 15 seconds, and the copper-based composite powder and the pure copper powder can be cold-pressed into a copper-based composite material blank.

[0043] In Example 3, the cold-pressed copper-based composite material blank is contained in a heat-resistant stainless steel 310S mold so that the copper-based composite material blank is located inside the female mold between the two punches. In the same way, multiple copper-based composite material blanks can be contained in multiple heat-resistant stainless steel 310S molds respectively, and then multiple heat-resistant stainless steel 310S molds containing copper-based composite material blanks are placed in a vacuum hot pressing furnace. After vacuuming, the inside of the vacuum hot pressing furnace is made to be 0.01pa, and then the copper-based composite material blank is heated by the vacuum hot pressing furnace at a heating temperature of 800-1050°C, and a unit pressure of 50-100MP is applied, and then the heat preservation is carried out for 60-180min, so as to realize one-time forming of the copper-based composite material and achieve the required density, strength and mechanical properties. Then, the copper-based composite material is taken out of the furnace and cooled. After cooling, the copper-based composite material is post-processed by burr cleaning, polishing and the like so as to achieve the required surface quality.

[0044] In summary, if Figure 1-4 As shown, the vacuum hot-pressing copper-based composite material preparation process, during the preparation, first tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder are sieved respectively, the particles of tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder are controlled within a specific range, and then chemical etching, ultrasonic cleaning and drying are performed to eliminate oxides or impurities on the surface and inside of tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder, and then tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder are mixed and stirred, and then vacuum ball milled to prepare copper-based composite powder, and then the copper-based composite powder and pure copper powder are cold pressed (such as Figure 2 After cold pressing, the cold pressed copper-based composite blank is placed in a heat-resistant stainless steel 310S mold (as shown in FIG. Figure 3 As shown), then put it into the vacuum hot pressing furnace, and go through the process of vacuuming - heating - keeping warm - taking it out of the furnace (as shown Figure 4 As shown), the copper-based composite material can be formed in one go to achieve the required density, strength and mechanical properties. After the copper-based composite material is taken out of the furnace, it needs to be post-processed such as burr cleaning and polishing to achieve the required surface quality.

[0045] Finally, a few points should be explained: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, which may refer to mechanical connection or electrical connection, or internal communication between two components, or direct connection. "upper", "lower", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may change;

[0046] Secondly: In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0047] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A vacuum hot-pressing copper-based composite material preparation process, characterized in that: The following steps are involved: Step 1: pre-treat tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder, then add tungsten powder, molybdenum powder, chromium powder, tin powder and zinc powder to copper powder for mixing, and then vacuum ball mill to prepare copper-based composite powder; Step 2: cold pressing the copper-based composite powder and the pure copper powder; Step 3: Place the cold-pressed copper-based composite material blank into a heat-resistant stainless steel 310S mold; Step 4: Place the heat-resistant stainless steel 310S mold containing the copper-based composite material blank into a vacuum hot pressing furnace, and after vacuuming - heating - heat preservation - taking out of the furnace, the one-time forming of the copper-based composite material is achieved.

2. A vacuum hot-pressing copper-based composite material preparation process according to claim 1, characterized in that: The pretreatment method in step one is to first screen the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder respectively, control the particles of the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder within a specific range, and then chemically etch, ultrasonically clean and dry the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder to eliminate oxides or impurities on the surface and inside of the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder.

3. The vacuum hot-pressing copper-based composite material preparation process according to claim 1, characterized in that: In step 1, the mixing time of the tungsten powder, molybdenum powder, chromium powder, tin powder, zinc powder and copper powder is 40-50 minutes, and the stirring speed is 10-30r / min.

4. The vacuum hot-pressing copper-based composite material preparation process according to claim 1, characterized in that: In step 1, the ball milling speed is 100-300 r / min, the ball milling time is 8 hours, the ball milling is performed for 30 minutes with a rest period of 15 minutes, and the pressure in the ball milling tank is 0-1P.

5. The vacuum hot-pressing copper-based composite material preparation process according to claim 1, characterized in that: In step 2, the copper-based composite powder and the pure copper powder are cold pressed at a pressure of 500-700 MPa, and the density of the copper-based composite powder and the pure copper powder is 7.5-8.0 g / cm, and then the pressure is maintained for 15 seconds.

6. The vacuum hot-pressing copper-based composite material preparation process according to claim 1, characterized in that: In step 2, the mold for cold pressing includes a female mold, an upper punch and a lower punch. During cold pressing, the lower punch is located below the inner cavity of the female mold, and the upper punch is located above the inner cavity of the female mold. The copper-based composite powder and the pure copper powder are located between the upper punch and the lower punch inside the female mold. The copper-based composite powder and the pure copper powder can be cold pressed into a copper-based composite material blank.

7. The vacuum hot-pressing copper-based composite material preparation process according to claim 1, characterized in that: In step three, the heat-resistant stainless steel 310S mold includes a female mold and a punch, the female mold is located between two punches, and the copper-based composite material blank is located inside the female mold between the two punches.

8. The vacuum hot-pressing copper-based composite material preparation process according to claim 1, characterized in that: In step 4, the vacuum hot pressing furnace is evacuated to 0.01 Pa, the heating temperature is 800-1050° C., and the insulation time is 60-180 min.

9. The vacuum hot-pressing copper-based composite material preparation process according to claim 1, characterized in that: In step 4, after the copper-based composite material is taken out of the furnace, it needs to be post-processed such as burr removal and polishing to achieve the required surface quality.

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