JP2006328542A - Copper-based alloy material and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a copper-based alloy material having the surface superior in abrasion resistance and corrosion resistance formed by coating the surface of the copper-based alloy material with Sn and then appropriately forming a high-hardness Cu-Sn-based intermetallic compound in the treated surface layer of the material by heat treatment, and to provide a manufacturing method therefor. <P>SOLUTION: The copper-based alloy material having superior various characteristics such as high hardness, high strength and high electroconductivity is manufactured by the steps of: coating the surface of a Cu-Ni-Sn-P copper alloy or a Cu-Ni-Sn-P- (one or more elements of subcomponents including Fe, Co, Zn, Ti and Mg) copper alloy material with Sn; and then heat-treating the material on a predetermined condition to form a Cu-Sn-based coating film made from the intermetallic compound with high hardness on the surface of the material. The manufacturing method therefor is also provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a copper-based alloy material (including copper and a copper alloy; hereinafter simply referred to as “copper-based alloy material”) and a method for producing the same. Wear resistant to surfaces that require low friction during insertion and removal, such as the surface of connectors, and those that require frequent insertion and removal, such as charging sockets for electric vehicles, and motors such as brushes. The present invention relates to a copper-based alloy material having a surface that is required for wear resistance and a surface that is required for wear resistance and corrosion resistance such as a battery terminal, and a method for producing the same.

  With the recent development of electronics, the electrical wiring of various machines has become more complex and highly integrated, and accordingly, the number of connectors has been increased. A conventional Sn-plated connector has a problem of increased friction when it is inserted and removed, making it difficult to insert and remove the connector.

  In addition, current electric vehicles require charging once or more a day, and it is necessary to ensure wear resistance of the charging socket parts. On top of that, a large current of 10 A or more flows, so that heat generation is large, and there is a problem that the plating is peeled off by a conventional method such as Sn plating.

  It has become clear that conventional surface treatment methods cannot cope with the above problems, and there is also a conventional technology for thermally diffusing the copper-based alloy material proposed by the present invention after surface treatment. However, since the conventional technology merely prevents the surface treatment layer from being peeled off due to processing or thermal influence due to the diffusion between the surface treatment layer and the material, it still cannot cope with the above problem. .

The present invention solves the above-described problems, and after the surface of the copper-based alloy material is coated with Sn or Sn alloy, heat treatment is performed, and the surface treatment layer of the material is made of a very hard Cu-Sn based metal. By appropriately forming a compound (Cu ₃ Sn, Cu ₄ Sn, etc.), for example, a copper base having a small surface friction coefficient suitable for a connector, a charging socket of an electric vehicle, etc., and having a surface excellent in wear resistance An alloy material and a manufacturing method thereof are proposed.

In the present invention, the Cu-Sn intermetallic compound (Cu ₃ Sn, Cu ₄₎ , which was difficult and impossible in the prior art, is limited by limiting the film thickness of Sn and the heat treatment conditions to be coated on a copper-based alloy material having a specific composition. (Sn etc.) is a technology developed with the knowledge that the surface hardness can be remarkably improved by positively forming, such as a connector for an automobile or a charging socket for an electric automobile. The present invention provides a copper base alloy material having a small friction coefficient and excellent wear resistance and a method for producing the same.

  That is, the present invention is "a copper-based alloy material characterized by having a high hardness intermetallic compound coating of Cu and Sn on the surface"

  In addition, the present invention includes “in weight percent, Ni: 0.1% to 15%, Sn: 0.1 to 10%, P: 0.005% to 0.5%, with the balance being Cu and inevitable impurities. A copper-based alloy material characterized by having a high-hardness intermetallic compound coating of Cu and Sn on the surface thereof,

  Further, the present invention includes "in weight percent, Ni: 0.1 to 15%, Sn: 0.1 to 10%, P: 0.005 to 0.5%, and Fe, Co, Zn, Ti" , Mg, Zr, Ca, Si, Mn, Cd, Al, Pb, Be, Te, In, Ag, B, Y, La, Cr, Ce, and Au, in a total amount A copper-based alloy material characterized by comprising 0.01 to 40%, the balance being Cu and inevitable impurities, and having a high-hardness intermetallic compound coating of Cu and Sn on the surface "

  In addition, the present invention provides a “copper characterized by forming a high-hardness intermetallic compound film of Cu and Sn on the surface of the material by coating the surface of the material of the copper-based alloy material with Sn and then performing a heat treatment. Manufacturing method of the base alloy material,

  Further, the present invention includes "in weight percent, Ni: 0.1 to 15%, Sn: 0.1 to 10%, P: 0.005 to 0.5%, with the balance being Cu and inevitable impurities. A method for producing a copper-based alloy material, characterized in that a high-hardness intermetallic compound film of Cu and Sn is formed on the surface of the material by coating the surface of the copper-based alloy material with Sn, followed by heat treatment. And

  Further, the present invention includes "in weight percent, Ni: 0.1 to 15%, Sn: 0.1 to 10%, P: 0.005 to 0.5%, and Fe, Co, Zn, Ti" , Mg, Zr, Ca, Si, Mn, Cd, Al, Pb, Be, Te, In, Ag, B, Y, La, Cr, Ce, and Au, in a total amount A high-hardness intermetallic compound of Cu and Sn is coated on the surface of the copper-based alloy material containing 0.01 to 40%, the remainder comprising Cu and inevitable impurities, and then heat-treated. The present invention provides a method for producing a copper-based alloy material characterized by forming a film.

  In the present invention, the Sn coating thickness is 0.5 to 20 μm, preferably 1 to 10 μm, and most preferably 1 to 5 μm. The heat treatment conditions after coating are as follows: the temperature is 100 to 600 ° C. and the processing time is 0. 0.5 to 24 hours is preferable, more preferably the temperature is 200 to 500 ° C. and the processing time is 0.5 to 24 hours, and most preferably the temperature is 250 to 500 ° C. and the processing time is 3 to 10 hours.

  In the present invention, the composition ratio of Ni: P is preferably in the range of 5 to 50 in terms of weight percentage.

  Next, the contents of the present invention will be specifically described. First, selection of the additive element of the copper-based alloy material according to the present invention and the reason for limiting the range of the content will be described as follows.

(1) Ni
Ni is an element that contributes to improving the strength, elasticity, heat resistance, stress relaxation resistance, and the like of the material, and further improves electrical conductivity by forming and dispersing P with a compound. In addition, the Cu—Sn diffusion layer can be effectively formed by heat treatment after the surface coating treatment. Further, a part of the added Ni diffuses to the surface treatment layer side, and an intermetallic compound such as Ni—Sn, Cu—Ni—Sn is formed at the interface or diffusion layer, and the strength, hardness, adhesion and Improve corrosion resistance.

  In order to exhibit the above effect, it is necessary to contain 0.1 wt% or more. If it exceeds 15 wt%, the electrical conductivity is remarkably lowered, which is economically disadvantageous. Therefore, the Ni content is preferably in the range of 0.1 to 15 wt%.

(2) Sn
Sn is dissolved in the raw material Cu matrix to improve the strength, elasticity and corrosion resistance. However, if the Sn content is less than 0.1 wt%, the strength and elasticity are not sufficiently improved. If the Sn content exceeds 10 wt%, the electrical conductivity and workability are significantly reduced, and the migration resistance may be further deteriorated. There is. Therefore, the Sn content is preferably in the range of 0.1 to 10 wt%.

(3) P
P forms a compound with Ni and disperses and precipitates, thereby improving electrical conductivity and improving strength, elasticity, and stress relaxation resistance. However, if the P content is less than 0.005 wt%, the above effects cannot be obtained sufficiently. If the P content exceeds 0.5 wt%, the electrical conductivity, workability and solder weather resistance are significantly reduced even in the presence of Ni. Further, the migration resistance is reduced. Accordingly, the P content is preferably in the range of 0.005 to 0.5 wt%.

(4) About the composition ratio of Ni: P In addition, in the copper-based alloy material according to the present invention, a part of the added Ni and P forms a Ni-P-based compound, which is uniformly finely dispersed and precipitated. In addition to electrical conductivity, strength, elasticity, and stress relaxation resistance can be improved. Therefore, it is preferable to limit the weight percentage ratio of Ni and P (Ni / P), and the Ni / P weight percentage composition ratio is preferably in the range of 5-50.

(5) Subcomponents As subcomponents, Fe, Co, Zn, Ti, Mg, Zr, Ca, Si, Mn, Cd, Al, Pb, Be, Te, In, Ag, B, Y, La, Cr , Ce, Au, and the like, the above characteristics are further improved by containing 0.01 to 40 wt% of one or more of the groups.

  Here, Zn not only further improves the plating weather resistance of the copper-based alloy material, but also has advantages such as being economical because the specific gravity is small and the weight of the alloy is reduced and it is inexpensive. However, since the stress corrosion cracking resistance and electrical conductivity are lowered when the amount added is increased, the Zn content is preferably in the range of 0.01 to 40 wt%.

  For other elements Fe, Co, Zn, Ti, Mg, Zr, Ca, Si, Mn, Cd, Al, Pb, Be, Te, In, Al, B, Y, La, Cr, Ce, Au, Their inclusion improves the properties such as strength and elasticity. Moreover, these subcomponents are effective in improving strength, elasticity and workability without deteriorating the electrical conductivity of the copper-based alloy material according to the present invention.

  However, from the viewpoint of electrical conductivity, molding processability, ease of production, etc., more preferable ranges are Fe: 0.01-5 wt%, Co: 0.01-5 wt%, Ti: 0.01-5 wt% Mg: 0.01-3 wt%, Zr: 0.01-3 wt%, Ca: 0.01-1 wt%, Si: 0.01-3 wt%, Mn: 0.01-10 wt%, Cd: 0. 01-5 wt%, Al: 0.01-10 wt%, Pb: 0.01-5 wt%, Be: 0.01-3 wt%, Te: 0.01-5 wt%, In: 0.01-5 wt%, Ag: 0.01-5 wt%, B: 0.01-1 wt%, Y: 0.01-5 wt%, La: 0.01-5 wt%, Cr: 0.01-5 wt%, Ce: 0.01 -5 wt%, Au: 0.01-5 wt%.

(6) About the amount of copper component in the copper-based alloy material The most commonly added element to Cu as a copper alloy that can be produced industrially is Zn, but its maximum content is 45 wt%, and Cu-Sn. In order to effectively form an intermetallic compound (Cu ₃ Sn, Cu ₄ Sn, etc.), it is necessary to contain Cu at least 55 wt% or more.

  The copper-based alloy material prepared as described above has excellent heat resistance, can sufficiently withstand thermal diffusion after coating, and can effectively form a Cu-Sn intermetallic compound by thermal diffusion. it can.

  Next, the reason for limiting the Sn coating thickness and the diffusion treatment conditions will be described.

(7) Sn coating thickness When the Sn coating thickness is less than 0.5 μm, the corrosion resistance tends to decrease, and corrosion due to H ₂ S gas may be a problem. In addition, the intermetallic compound layer becomes thin, which is disadvantageous in terms of physical properties. When the thickness of the Sn coating exceeds 20 μm, the thickness of the diffusion layer becomes too thick, and a decrease in molding processability such as cracking during processing is recognized. Further, the fatigue characteristics are reduced and economically disadvantageous. The problem of becoming.

  Therefore, the thickness of the Sn coating is preferably in the range of 0.5 to 20 μm, more preferably in the range of 1 to 10 μm, and most preferably in the range of 1 to 5 μm.

  As a method for forming the Sn coating layer, known methods such as electroplating, chemical plating, vapor deposition, and hot dipping can be applied, but electroplating and hot dipping are preferable from the viewpoint of coating adhesion, uniformity, and economy. It is.

  Further, Sn to be coated may be a Sn—Pb alloy having a Sn content of 50% or more.

(8) Heat treatment conditions Heat treatment at a temperature lower than 100 ° C is disadvantageous economically because the time required for Sn diffusion becomes too long. When the temperature exceeds 600 ° C., the material copper-based alloy material starts to soften in a short time, so that the strength and hardness decrease.

  When the heat treatment time is less than 0.5 hours, Sn diffusion is insufficient, and it becomes impossible to form an effective intermetallic compound, and when it exceeds 24 hours, it is economically disadvantageous and productivity is lowered.

  Accordingly, the heat treatment conditions are preferably a temperature of 100 to 600 ° C. and a treatment time of 0.5 to 24 hours, and a more preferred range is a temperature of 200 to 500 ° C. and a treatment time of 0.5 to 24 hours. The processing time is 3 to 10 hours at a temperature of 250 to 500 ° C.

  Further, the atmosphere during the heat treatment is economically advantageous because an inert or reducing atmosphere is not particularly required.

  By passing through the above steps, the adhesion between the intermetallic compound formed on the surface of the material and the material can be improved, and deterioration of the properties of the material due to annealing can be prevented. Furthermore, since the adhesion between the intermetallic compound and the material of the surface layer is improved, it is possible to prevent the peeling and cracking of the surface layer during bending and overhanging, and the generally difficult problem of the clad material that is said to be difficult Is also resolved.

  Further, after the heat treatment, the oxide film on the surface is more preferably removed by chemical treatment such as pickling or mechanical treatment such as buffing. By removing this film, further improvement in contact resistance value and solderability can be expected. Therefore, it is preferable to remove from the surface layer in the range of 0.01 to 0.2 μm.

  As will be apparent from the examples described later, the copper-based alloy material according to the present invention has high strength, high elasticity, and high electrical conductivity, and has excellent bending workability and overhang workability. Therefore, it is possible to manufacture a connector material that can be used for high-density automotive automobile electrical components and a charging socket material that can sufficiently handle high-current charging of an electric vehicle.

  In addition, since the copper-based alloy material produced by the method of the present invention has the above-described characteristics with excellent wear resistance and corrosion resistance, the materials for electric and electronic parts and It can be used in many fields as a structural material.

This invention copper base alloy material No. which has a chemical component (wt%) shown by Table 1 is shown. 1-2 and copper base alloy material No. for comparison. Each of Nos. 3 was rolled to 0.3 ^t mm and coated with Sn (by electroplating using a sulfuric acid bath), and then heat-treated. The heat treatment conditions were Sn film thickness 7.0 μm, heat treatment temperature 350 ° C., and treatment time 5 hours.

  Using the test materials obtained as described above, the hardness, tensile strength, spring limit value and conductivity were measured, and JIS-Z-2244, JIS-Z-2241, JIS-H-3130 and This was performed according to JIS-H-0505.

  As for bending workability, a 90 ° W bending test (CES-M-0002-6, R = 0.2 mm, rolling direction and vertical direction) was also performed, and a mark with a good crest surface at the center was marked with a circle. These were evaluated as Δ marks and those with cracks as X marks. The stretch workability was subjected to an Erichsen test and was in accordance with the JIS-Z-2247A method.

  The above measurement results are shown in Table 2. From the results in Table 2, No. 1 according to the present invention. 1, No. 1 The copper base alloy material No. 2 has a markedly improved surface hardness, an excellent balance of tensile strength, spring limit value and electrical conductivity, and also has good bending workability and overhang workability. Therefore, it is a copper-based alloy material having very excellent characteristics for applications such as connectors and charging sockets. On the other hand, No. out of the component composition range of the present invention. It can be seen that the comparative alloy No. 3 is softened during heat treatment, and the hardness and tensile strength of the alloy are significantly reduced.

  Invention alloy No. As for Example 1, when the conditions of plating thickness and heat treatment temperature were changed, as in Example 1, the hardness, tensile strength, spring limit value, conductivity, bending workability, and overhang workability were measured. The results are shown in Table 3.

  From the results of Table 3, the surface hardness is remarkably improved by performing the heat treatment after the surface treatment. For example, when the plating thickness is 3.5 μm, 7.0 μm and the heat treatment temperature is 250, 350 ° C., the surface hardness and the base material hardness An improvement in the spring limit is also observed.

  However, if it deviates from the conditions according to the present invention, the characteristics of the surface and the material cannot be expressed sufficiently. For example, when the plating thickness is 7 μm and the heat treatment temperature is 700 ° C., the material hardness, tensile strength, spring limit value and bending workability are significantly deteriorated due to the softening during the heat treatment. It can be seen that the bending workability is significantly deteriorated.

Therefore, the copper alloy according to the present invention has excellent characteristics that can be sufficiently applied to uses such as connectors and charging sockets.

Claims (7)

The surface of a copper-based alloy material containing Ni: 0.1 to 15%, Sn: 0.1 to 10%, P: 0.005 to 0.5%, with the balance being Cu and inevitable impurities in weight% And a copper-based alloy material having an intermetallic compound layer of Cu and Sn. The surface of a copper-based alloy material containing Ni: 0.1 to 15%, Sn: 0.1 to 10%, P: 0.005 to 0.5%, with the balance being Cu and inevitable impurities in weight% A copper-based alloy material having an intermetallic compound layer of Ni-Sn and / or Cu-Ni-Sn and having an intermetallic compound layer of Cu and Sn on the outermost surface. The surface of a copper-based alloy material containing Ni: 0.1 to 15%, Sn: 0.1 to 10%, P: 0.005 to 0.5%, with the balance being Cu and inevitable impurities in weight% And a copper-based alloy material having a Cu—Ni—Sn intermetallic compound layer. In wt%, Ni: 0.1-15%, Sn: 0.1-10%, P: 0.005-0.5%, Fe, Co, Zn, Ti, Mg, Zr, Ca , Si, Mn, Cd, Al, Pb, Be, Te, In, Ag, B, Y, La, Cr, Ce, Au, in a total amount of 0.01 to 40% A copper-based alloy material having an intermetallic compound layer of Cu and Sn on the surface of a copper-based alloy material that contains Cu and inevitable impurities. In wt%, Ni: 0.1-15%, Sn: 0.1-10%, P: 0.005-0.5%, Fe, Co, Zn, Ti, Mg, Zr, Ca , Si, Mn, Cd, Al, Pb, Be, Te, In, Ag, B, Y, La, Cr, Ce, Au, in a total amount of 0.01 to 40% It has an intermetallic compound layer of Ni-Sn and / or Cu-Ni-Sn on the surface of the copper-based alloy material that contains Cu and inevitable impurities, and the Cu and Sn intermetallic compound layer on the outermost surface A copper-based alloy material. In wt%, Ni: 0.1-15%, Sn: 0.1-10%, P: 0.005-0.5%, Fe, Co, Zn, Ti, Mg, Zr, Ca , Si, Mn, Cd, Al, Pb, Be, Te, In, Ag, B, Y, La, Cr, Ce, Au, in a total amount of 0.01 to 40% A copper-based alloy material comprising a Cu-Ni-Sn intermetallic compound layer on the surface of a copper-based alloy material that contains Cu and inevitable impurities. A tensile strength of 504N / mm ² or more, and wherein the spring limit value is 442N / mm ² or more, a copper-based alloy material according to claims 1-6.