Copper alloy plastic working material and component for electronic / electrical equipment

Abstract

The present invention is characterized by having: a composition having a Fe content in the range of 0.08-0.17 mass% and a P content in the range of 0.025-0.06 mass%, with the remainder being Cu and unavoidable impurities; a conductivity of 75% IACS or greater and a Vickers surface hardness of 130 HV or greater at room temperature; and a Vickers surface hardness of 40 HV or greater at 400°C.

Description

Copper alloy plastically formed materials, and components for electronic and electrical equipment.

[0001] The present invention relates to a copper alloy plastically formed material suitable for use as a material for, for example, electric vehicles (EVs), aircraft (EVTOLs, electric vertical take-off and landing aircraft, etc.), home appliances, semiconductor components such as lead frames, printed circuit boards, heat sinks, switchgear components, busbars, connectors, and other electrical and electronic equipment components, as well as electrical and electronic equipment components made from this copper alloy plastically formed material. This application claims priority based on Japanese Patent Application No. 2024-232538, filed in Japan on December 27, 2024, the contents of which are incorporated herein by reference.

[0002] Traditionally, copper materials with high conductivity and thermal conductivity have been used for electronic and electrical equipment components such as terminals, busbars, lead frames, and heat dissipation members, as they require both electrical conductivity and heat dissipation properties. Specifically, a conductivity of 75% IACS or higher is sufficient to exhibit adequate electrical conductivity and heat dissipation properties. Furthermore, in recent years, the increased performance and miniaturization of electronic and electrical equipment components have led to complex shapes and the demand for high dimensional accuracy. For this reason, high mechanical properties and a uniform structure are also required; for example, a Vickers hardness of 130 HV or higher is required. Moreover, the manufacturing process for these electronic and electrical equipment components involves bonding processes that apply heat and load, such as die bonding and wire bonding. If the copper material cannot withstand the heat and load of the bonding process, it will deform and its operational reliability will decrease. Therefore, high heat resistance is also required for copper materials. It should be noted that high heat resistance at a heating temperature of 400°C is sufficient to suppress deformation.

[0003] For the various copper alloy applications mentioned above, Cu-Fe-P alloys containing Fe and P have conventionally been widely used. Cu-Fe-P alloys are precipitation-strengthened alloys in which intermetallic compounds such as Fe or Fe-P are deposited in a copper matrix. They are widely used in various applications due to their excellent strength, electrical conductivity, and thermal conductivity. However, within this composition range, there are limitations to the mechanical properties, and if the mechanical properties are forcibly improved, the heat resistance decreases. Therefore, there is a problem in that there are limitations to both mechanical properties and heat resistance.

[0004] Therefore, techniques have been proposed to improve mechanical properties and heat resistance by adding elements other than Fe and P. For example, Patent Document 1 discloses a technique for adding Co, Ni, and Mg in addition to Fe and P; Patent Document 2 discloses a technique for adding Sn, as well as Co, Al, Cr, Mg, Mn, Ca, Pb, Ni, Ti, Zr, Si, and Ag in addition to Fe and P; and Patent Document 3 discloses a technique for adding Co and Ni in addition to Fe and P.

[0005] Japanese Unexamined Patent Publication No. 2004-232069 (A) Japanese Unexamined Patent Application No. 2016-044330 (A) Japanese Unexamined Patent Application No. 2013-095934 (A)

[0006] Incidentally, in Patent Documents 1 to 3, there was a risk that adding elements other than Fe and P in excess would significantly reduce conductivity. Furthermore, adding elements other than Fe and P increased manufacturing costs. In Patent Documents 1 and 3, the hardness was evaluated at room temperature after heating to 400°C as an evaluation of heat resistance. However, in the actual joining process of electronic and electrical equipment components, deformation occurs under both heat and load. This is because, unlike applying load at room temperature, dynamic recovery and recrystallization occur when load is applied during heating. Therefore, the evaluation of heat resistance that can withstand joining needs to be done during heating.

[0007] Furthermore, when the hardness was high, there was a problem of deformation occurring during complex molding processes. This is because, in conventional manufacturing processes, dislocations introduced in the rolling process performed before the final heat treatment process are not uniformly removed in the final heat treatment process, and the subsequent final rolling process results in uneven mechanical properties within the material. Specifically, there is a difference in hardness between the surface and the interior of the material, and the higher the rolling ratio in the final rolling process, the greater this difference becomes, leading to deformation during molding.

[0008] The present invention has been made in view of the circumstances described above, and aims to provide a copper alloy plastic processed material that has excellent conductivity and hardness, and can suppress deformation even when a load is applied at high temperatures, without adding large amounts of elements other than Fe and P, and electrical and electronic equipment components made from this copper alloy plastic processed material.

[0009] To solve the above problems, the copper alloy plastic workpiece according to embodiment 1 of the present invention has a composition in which the Fe content is in the range of 0.08% by mass or more and 0.17% by mass or less, the P content is in the range of 0.025% by mass or more and 0.06% by mass or less, and the remainder is Cu and unavoidable impurities, the conductivity is 75% IACS or more, the surface Vickers hardness at room temperature is 130 HV or more, and the surface Vickers hardness at 400°C is 40 HV or more.

[0010] According to the copper alloy plastic deformation material of embodiment 1 of the present invention, the composition has an Fe content in the range of 0.08% by mass or more and 0.17% by mass or less, a P content in the range of 0.025% by mass or more and 0.06% by mass or less, and the remainder being Cu and unavoidable impurities. As a result, intermetallic compounds such as Fe or Fe-P are precipitated in the copper matrix, which improves strength while maintaining excellent electrical and thermal conductivity.

[0011] Specifically, since its conductivity is 75% IACS or higher, it has excellent electrical and thermal conductivity. Furthermore, since its surface Vickers hardness at room temperature is 130 HV or higher, deformation during processing can be suppressed, allowing for processing with good dimensional accuracy. In addition, since its surface Vickers hardness at 400°C is 40 HV or higher, deformation can be suppressed even when a load is applied at high temperatures.

[0012] The copper alloy plastic workpiece of aspect 2 of the present invention is characterized in that, in the copper alloy plastic workpiece of aspect 1 of the present invention, it further contains Zn in a range of 0.005% by mass or more and 0.1% by mass or less. According to the copper alloy plastic workpiece of aspect 2 of the present invention, since it further contains Zn in a range of 0.005% by mass or more and 0.1% by mass or less, the solder heat release resistance can be improved.

[0013] The copper alloy plastic workpiece of embodiment 3 of the present invention is a copper alloy plastic workpiece of embodiment 1 or embodiment 2 of the present invention, wherein the Vickers hardness H of the surface layer in cross-section is Ｓ and internal Vickers hardness H Ｉ All of these have a Vickers hardness of 130 HV or higher, and the surface Vickers hardness is H Ｓand the Vickers hardness H inside Ｉ and the ratio H to Ｓ / H Ｉ is 0.95 or more. According to the copper alloy wrought product of Aspect 3 of the present invention, the Vickers hardness H of the surface layer in the cross section Ｓ and the Vickers hardness H inside Ｉ are both 130 HV or more, and the ratio H of the Vickers hardness H of the surface layer Ｓ and the Vickers hardness H inside Ｉ to Ｓ / H Ｉ is 0.95 or more, so it is sufficiently hard and has a uniform hardness throughout, and deformation during processing can be further suppressed, and it can be processed stably with good dimensional accuracy.

[0014] The copper alloy wrought product of Aspect 4 of the present invention is a rolled plate having a thickness within the range of 0.1 mm or more and 10 mm or less in any one of the copper alloy wrought products of Aspects 1 to 3 of the present invention. According to the copper alloy wrought product of Aspect 4 of the present invention, since it is a rolled plate having a thickness within the range of 0.1 mm or more and 10 mm or less, for example, various shaped parts can be formed with good dimensional accuracy by punching.

[0015] The copper alloy wrought product of Aspect 5 of the present invention has a metal plating layer on the surface in any one of the copper alloy wrought products of Aspects 1 to 4 of the present invention. According to the copper alloy wrought product of Aspect 5 of the present invention, since it has a metal plating layer on the surface, it is particularly suitable as a material for parts for electronic and electrical equipment such as terminals, bus bars, lead frames, and heat radiating members.

[0016] The part for electronic and electrical equipment of Aspect 6 of the present invention is made of any one of the copper alloy wrought products of Aspects 1 to 5 of the present invention. According to the part for electronic and electrical equipment of Aspect 6 of the present invention, since it is manufactured using the above copper alloy wrought product, it can exhibit excellent characteristics as terminals, bus bars, lead frames, heat radiating members, etc.

[0017] It is possible to provide a copper alloy wrought material that is excellent in conductivity and hardness without adding a large amount of elements other than Fe and P and can suppress deformation even when a load is applied at a high temperature, and a component for an electric and electronic device made of this copper alloy wrought material.

[0018] It is a flowchart of the manufacturing method of the copper alloy wrought material which is this embodiment.

[0019] Hereinafter, a copper alloy wrought material according to an embodiment of the present invention and a component for an electric and electronic device will be described. The copper alloy wrought material in this embodiment has a composition in which the Fe content is in the range of 0.08 mass% or more and 0.17 mass% or less, the P content is in the range of 0.025 mass% or more and 0.06 mass% or less, and the balance is Cu and inevitable impurities. In the copper alloy wrought material in this embodiment, Zn may be further contained in the range of 0.005 mass% or more and 0.1 mass% or less.

[0020] And in the copper alloy wrought material of this embodiment, the conductivity is 75% IACS or more, and the Vickers hardness of the surface at room temperature is 130 HV or more. Further, in the copper alloy wrought material of this embodiment, the Vickers hardness of the surface at 400 ° C. is 40 HV or more.

[0021] In the copper alloy wrought material of this embodiment, the Vickers hardness H of the surface layer in the cross section Ｓ and the Vickers hardness H of the inside Ｉ are both preferably 130 HV or more.

[0022] Furthermore, in the copper alloy wrought material of this embodiment, the Vickers hardness H of the surface layer Ｓ and the Vickers hardness H of the inside Ｉ The ratio H of Ｓ / H Ｉ is preferably 0.95 or more.

[0023] Also, in the copper alloy wrought material of this embodiment, a rolled plate having a thickness in the range of 0.1 mm or more and 10 mm or less is preferable.

[0024] Furthermore, in the copper alloy plastically deformed material of this embodiment, it is preferable to have a metal plating layer on the surface.

[0025] The reasons for specifying the component composition and various properties of the copper alloy plastically deformed material of this embodiment as described above are explained below.

[0026] (Fe) Fe dissolves in the copper matrix and generates Fe or Fe-P precipitate particles. These Fe or Fe-P precipitate particles 12 are dispersed in the matrix 11, improving strength, hardness, and heat resistance without reducing electrical conductivity. If the Fe content is less than 0.08 mass%, the strength, hardness, and heat resistance cannot be sufficiently improved. On the other hand, if the Fe content exceeds 0.17 mass%, the electrical conductivity and thermal conductivity decrease. Therefore, in this embodiment, the Fe content is set within the range of 0.08 mass% to 0.17 mass%.

[0027] Furthermore, in order to ensure that the above-mentioned effects are reliably achieved, it is preferable to set the lower limit of the Fe content to 0.09 mass% or more, and more preferably to 0.10 mass% or more. In addition, in order to further suppress the decrease in electrical conductivity and thermal conductivity, it is preferable to set the upper limit of the Fe content to 0.16 mass% or less, and more preferably to 0.15 mass% or less.

[0028] (P) P is an element that has a deoxidizing effect. Also, as described above, together with Fe, it forms Fe-P precipitate particles, improving strength, hardness, and heat resistance without reducing conductivity. Here, if the P content is less than 0.025 mass%, the strength, hardness, and heat resistance cannot be sufficiently improved. On the other hand, if the P content exceeds 0.06 mass%, the conductivity and thermal conductivity decrease. Therefore, in this embodiment, the P content is set within the range of 0.025 mass% to 0.06 mass%.

[0029] Furthermore, in order to ensure that the above-mentioned effects are reliably achieved, it is preferable that the lower limit of the P content be 0.030% by mass or more, and more preferably 0.035% by mass or more. In addition, in order to further suppress the decrease in electrical conductivity and thermal conductivity, it is preferable that the upper limit of the P content be 0.055% by mass or less, and more preferably 0.050% by mass or less.

[0030] (Zn) In the copper alloy plastic work material of this embodiment, Zn may be added in addition to Fe and P. Adding Zn can improve solder heat release resistance. Here, it is preferable that the Zn content be 0.005% by mass or more. On the other hand, by setting the Zn content to 0.1% by mass or less, the decrease in electrical conductivity and thermal conductivity can be further suppressed. Therefore, in this embodiment, when Zn is added to improve solder heat release resistance, it is preferable that the Zn content be within the range of 0.005% by mass or more and 0.1% by mass or less.

[0031] Furthermore, in order to ensure that the above-mentioned effects are reliably achieved, it is even more preferable to set the lower limit of the Zn content to 0.008% by mass or more, and more preferably to 0.01% by mass or more. In addition, in order to further suppress the decrease in electrical conductivity and thermal conductivity, it is even more preferable to set the upper limit of the Zn content to 0.08% by mass or less, and more preferably to 0.05% by mass or less. Furthermore, if Zn is not intentionally added, the Zn content may be less than 0.005% by mass.

[0032] (Unavoidable impurities: Co, Al, Cr, Mg, Mn, Ca, Pb, Ni, Ti, Zr, Si, As, Sn) Co, Al, Cr, Mg, Mn, Ca, Pb, Ni, Ti, Zr, Si, As, Sn are unavoidable impurities contained in the above-mentioned copper alloy plastic processing material. Here, if the content of the unavoidable impurities Co, Al, Cr, Mg, Mn, Ca, Pb, Ni, Ti, Zr, Si, As, Sn is high, the electrical conductivity and thermal conductivity may decrease. In addition, if these elements are intentionally added, the manufacturing cost will increase.

[0033] Therefore, in this embodiment, it is preferable to limit the total content of unavoidable impurities Co, Al, Cr, Mg, Mn, Ca, Pb, Ni, Ti, Zr, Si, As, and Sn to 0.1% by mass or less. Furthermore, it is even more preferable that the total content of unavoidable impurities Co, Al, Cr, Mg, Mn, Ca, Pb, Ni, Ti, Zr, Si, As, and Sn be 0.09% by mass or less, and even more preferable that be 0.08% by mass or less.

[0034] (Other unavoidable impurities) In addition to the Fe, P, Zn and Co, Al, Cr, Mg, Mn, Ca, Pb, Ni, Ti, Zr, Si, As, and Sn mentioned above, other unavoidable impurities include, for example, Sr, Ba, rare earth elements, Be, H, Li, B, N, O, F, Na, S, Cl, K, Ga, Ge, Se, Br, Rb, Tc, Ru, Rh, Pd, Ag, Cd, In, Sb, Te, I, Cs, Hf, Ta, Re, Os, Ir, Pt, Au, Hg, Tl, Bi, etc. These unavoidable impurities may be present in amounts that do not affect the properties. Since these unavoidable impurities may reduce conductivity, it is preferable that their total amount be 0.1% by mass or less, more preferably 0.05% by mass or less, even more preferably 0.03% by mass or less, and even more preferably 0.01% by mass or less.

[0035] (Conductivity) In the copper alloy plastic processed material of this embodiment, the conductivity is 75% IACS or higher, making it particularly suitable as a material for electrical and electronic equipment components such as busbars. Preferably, the conductivity of the copper alloy plastic processed material of this embodiment is 78% IACS or higher, and more preferably 80% IACS or higher. Although not particularly limited, the conductivity at room temperature is substantially 95% IACS or lower.

[0036] (Vickers hardness of the surface at room temperature) In the copper alloy plastic workpiece of this embodiment, the surface Vickers hardness at room temperature is 130 HV or higher. This allows for suppression of deformation of the copper alloy plastic workpiece even when processed under load, enabling processing with good dimensional accuracy. Preferably, the surface Vickers hardness of the copper alloy plastic workpiece of this embodiment is 135 HV or higher, and more preferably 140 HV or higher. Although not particularly limited, the surface Vickers hardness at room temperature is substantially 190 HV or lower.

[0037] (Vickers hardness of the surface at 400°C) In the copper alloy plastic deformation material of this embodiment, the surface Vickers hardness at 400°C is set to 40 HV or higher. That is, in the copper alloy plastic deformation material of this embodiment, the Vickers hardness is evaluated while heated and held at 400°C. In this way, in the copper alloy plastic deformation material of this embodiment, sufficient hardness at 400°C is ensured, so deformation of the copper alloy plastic deformation material can be suppressed even when a load is applied at high temperatures. Therefore, for example, this copper alloy plastic deformation material can be joined well under high temperature conditions. The surface Vickers hardness of the copper alloy plastic deformation material of this embodiment at 400°C is preferably 43 HV or higher, and more preferably 45 HV or higher. Although not particularly limited, the surface Vickers hardness at 400°C is substantially 70 HV or lower.

[0038] (Vickers hardness H of the surface layer in cross-section) Ｓ and internal Vickers hardness H Ｉ ) In this embodiment of the plastically deformed copper alloy material, the Vickers hardness H of the surface layer in the cross-section Ｓ and internal Vickers hardness H Ｉ It is preferable that the Vickers hardness of the surface layer be 130 HV or higher. Ｓ and internal Vickers hardness H Ｉ Ratio H Ｓ / H ＩIt is preferable that the ratio is 0.95 or higher. In this embodiment, the "surface layer" refers to the region from the surface of the plastically deformed copper alloy material up to 25% of its thickness, and the "interior" refers to the region of 25% of the thickness centered on the thickness center of the plastically deformed copper alloy material.

[0039] In this embodiment of the plastically deformed copper alloy material, the Vickers hardness H of the surface layer in the cross-section Ｓ and internal Vickers hardness H Ｉ If the Vickers hardness of the surface layer is 130 HV or higher, sufficient hardness is ensured throughout the entire plastically deformed copper alloy material. Even when processed under load, deformation of the plastically deformed copper alloy material can be further suppressed, and processing can be performed with even greater dimensional accuracy. Ｓ and internal Vickers hardness H Ｉ Ratio H Ｓ / H Ｉ When the value is 0.95 or higher, there is no significant difference in hardness between the surface and the interior, resulting in a uniform structure, and it becomes possible to process copper alloy plastically deformed materials more stably.

[0040] Furthermore, the Vickers hardness H of the surface layer in the cross-section. Ｓ and internal Vickers hardness H Ｉ It is more preferably 135 HV or higher, and even more preferably 140 HV or higher. The Vickers hardness of the surface layer is not particularly limited, but is HV. Ｓ and internal Vickers hardness H Ｉ It is effectively below 200 HV. Also, the Vickers hardness of the surface is H Ｓ and internal Vickers hardness H Ｉ Ratio H Ｓ / H Ｉ It is more preferably 0.97 or higher, and even more preferably 0.98 or higher. Ｓ and internal Vickers hardness H Ｉ Ratio H Ｓ / H Ｉ The upper limit will effectively be 1.05 or less.

[0041] (Thickness of Rolled Sheet) In this embodiment of the plastically formed copper alloy material, it is preferable that the rolled sheet has a thickness of 0.1 mm or more and 10 mm or less. By performing press working, punching, etc. on a rolled sheet with a thickness of 0.1 mm or more and 10 mm or less, various shapes of electronic and electrical equipment parts can be manufactured. Furthermore, it is even more preferable that the lower limit of the thickness of the plastically formed copper alloy material (rolled sheet) in this embodiment be 0.12 mm or more, and more preferably 0.15 mm or more. Furthermore, it is even more preferable that the upper limit of the thickness of the plastically formed copper alloy material (rolled sheet) in this embodiment be 10 mm or less, and more preferably 3 mm or less.

[0042] (Metal Plating Layer) In the copper alloy plastic processed material of this embodiment, it is preferable that a metal plating layer is formed on the surface. The formation of a metal plating layer on the surface improves bonding with other components, making it particularly suitable as a material for electronic and electrical equipment parts. For example, Ag plating, Ag alloy plating, Sn plating, Sn alloy plating, etc., can be applied as the metal plating layer.

[0043] Next, an example of a method for manufacturing a copper alloy plastically deformed material according to this embodiment will be described with reference to the flow chart shown in Figure 1.

[0044] In the method for manufacturing a copper alloy plastically deformed material according to this embodiment, as shown in Figure 1, the process includes a melting and casting step S01, a homogenization / solution treatment step S02, an oxide film removal step S03, a rough machining step S04, an intermediate heat treatment step S05, a precipitation heat treatment step S06, a finishing step S07, and a strain removal step S08.

[0045] (Melting and Casting Process S01) First, the copper raw material is melted to obtain molten copper, to which the aforementioned elements are added to adjust the composition and produce molten copper alloy. Individual elements or master alloys can be used for the addition of various elements. Alternatively, raw materials containing the aforementioned elements may be melted together with the copper raw material. Recycled and scrap materials of this alloy may also be used. Here, the molten copper is preferably so-called 4NCu with a purity of 99.99% by mass or higher, or so-called 5NCu with a purity of 99.999% by mass or higher. Then, the composition-adjusted molten copper alloy is poured into a mold to produce an ingot. When considering mass production, it is preferable to use a continuous casting method or a semi-continuous casting method.

[0046] (Homogenization / Solution Treatment Process S02) Next, the obtained ingot is subjected to heat treatment to homogenize it. It is preferable to heat the ingot to a temperature of 400°C or higher and 1050°C or lower. There are no particular restrictions on the holding time in the homogenization process S02, but it is preferable to hold it for 1 hour or more and 24 hours or less. It is preferable to carry out this homogenization / solution treatment process S02 in a non-oxidizing or reducing atmosphere. Furthermore, in order to improve the efficiency of rough rolling and to homogenize the structure, which will be described later, hot working may be performed after the homogenization / solution treatment process S02. In this case, there are no particular restrictions on the processing method, and for example, rolling, drawing, extrusion, groove rolling, forging, pressing, etc., can be used. Furthermore, it is preferable that the hot working temperature be within the range of 400°C or higher and 1080°C or lower.

[0047] (Oxide film removal step S03) Next, the oxide film present on the surface after the homogenization / solution treatment step S02 is removed. Surface grinding is preferable to remove the oxide film. There are no particular restrictions on the amount of grinding, as long as the oxide film is sufficiently removed.

[0048] (Rough Machining Process S04) After the oxide film removal process S03, rough machining is performed to process the material into a predetermined shape. There are no particular limitations on the temperature conditions in this rough machining process, but in order to suppress recrystallization or to improve dimensional accuracy, it is preferable to use a temperature within the range of -200°C to 200°C, which is used for cold or warm rolling, and room temperature is particularly preferred. The processing rate is preferably 20% or more, and more preferably 30% or more. There are no particular limitations on the processing method, and for example, rolling, drawing, extrusion, groove rolling, forging, pressing, etc. can be used. In this embodiment, rolling is performed.

[0049] (Intermediate heat treatment step S05) After the rough machining step S04, an intermediate heat treatment is performed to soften the material for improved workability or to create a recrystallized structure. Preferably, the heat treatment temperature in this intermediate heat treatment step S05 is within the range of 500°C to 800°C, and the holding time at the heat treatment temperature is within the range of 20 seconds to 300 seconds. If there is a machining step after the intermediate heat treatment step S05, the introduced dislocations will not be uniformly removed in the precipitation heat treatment step S06 described later, resulting in uneven mechanical properties within the material in the finishing machining step S07, and deformation will occur when molding is performed. As a result, the surface Vickers hardness at 400°C may be less than 40 HV.

[0050] (Precipitation heat treatment step S06) After the intermediate heat treatment step S05, a precipitation heat treatment is performed to precipitate intermetallic compound particles such as Fe or Fe-P in the copper matrix. If the heat treatment temperature in this precipitation heat treatment step S06 is less than 400°C, it may not be possible to sufficiently precipitate intermetallic compound particles such as Fe or Fe-P, and the conductivity may become low. On the other hand, if the heat treatment temperature in the precipitation heat treatment step S07 exceeds 450°C, the heat resistance may become insufficient, and the Vickers hardness at 400°C may become low. Therefore, it is preferable that the heat treatment temperature in the precipitation heat treatment step S06 be within the range of 400°C to 450°C, and the holding time at the heat treatment temperature be within the range of more than 1 hour to 24 hours.

[0051] This deposition heat treatment step S06 improves conductivity. The heating rate and cooling rate can be set as appropriate, but it is preferable that the heating rate be 1°C / min or more and the cooling rate be 0.1°C / min or more up to 300°C.

[0052] (Finishing Process S07) A finishing process is performed to process the copper material after the precipitation heat treatment process S06 into a predetermined shape. If the processing rate in this finishing process S08 is less than 50%, the Vickers hardness of the surface at room temperature may be low. On the other hand, if the processing rate in the finishing process S07 exceeds 95%, the heat resistance will be insufficient, and the Vickers hardness at 400°C may be low. Therefore, it is preferable that the processing rate in the finishing process S07 be within the range of 50% to 95%.

[0053] The temperature conditions in this finishing process S07 are not particularly limited, but it is preferable to set them within the range of -200°C to 200°C for cold or warm rolling in order to suppress recrystallization or softening, and room temperature is particularly preferred. Furthermore, there are no particular limitations on the processing method, and for example, rolling, wire drawing, extrusion, groove rolling, forging, pressing, etc., can be used. In this embodiment, however, rolling is performed.

[0054] (Strain Removal Heat Treatment Process S08) If necessary, strain removal heat treatment may be performed to remove residual strain generated in the finishing process S07. The heat treatment temperature in the strain removal heat treatment process S08 is preferably in the range of 200°C to 700°C, and the holding time at the heat treatment temperature is preferably in the range of 1 second to 24 hours. When heat treatment is performed at a high temperature, it is preferable to shorten the holding time, and when heat treatment is performed at a low temperature, it is preferable to lengthen the holding time.

[0055] Through the above process, the copper alloy plastically formed material of this embodiment is produced. A plating process to form a metal plating layer may also be performed. Furthermore, the electronic and electrical equipment components of this embodiment are manufactured by applying processes such as press working, punching, and bending to the aforementioned copper alloy plastically formed material.

[0056] According to the copper alloy plastic processed material of this embodiment, which has the above configuration, the composition is such that the Fe content is in the range of 0.08 mass% to 0.17 mass%, the P content is in the range of 0.025 mass% to 0.06 mass%, and the remainder is Cu and unavoidable impurities. Therefore, by precipitating intermetallic compounds such as Fe or Fe-P in the copper matrix in the deposition heat treatment step S06, it is possible to improve strength while maintaining excellent electrical conductivity and thermal conductivity.

[0057] Furthermore, since its electrical conductivity is 75% IACS or higher, it has excellent electrical and thermal conductivity. In addition, since its surface Vickers hardness at room temperature is 130 HV or higher, deformation during processing can be suppressed, and processing can be done with good dimensional accuracy. Moreover, since its surface Vickers hardness at 400°C is 40 HV or higher, deformation can be suppressed even when a load is applied at high temperatures.

[0058] In the copper alloy plastically deformed material of this embodiment, if Zn is further included in the range of 0.005% by mass or more and 0.1% by mass or less, the Zn solid-solves in the copper matrix, improving the solder heat-resistant peelability.

[0059] In this embodiment of the plastically deformed copper alloy material, the Vickers hardness H of the surface layer in the cross-section Ｓ and internal Vickers hardness H Ｉ The Vickers hardness of the surface layer is 130HV or higher. Ｓ and internal Vickers hardness H Ｉ Ratio H Ｓ / H Ｉ When the value is 0.95 or higher, the entire copper alloy plastically deformed material is sufficiently hard and has a uniform hardness, which further suppresses deformation during processing and allows for stable processing with good dimensional accuracy.

[0060] In the copper alloy plastically formed material of this embodiment, if the rolled sheet has a thickness in the range of 0.1 mm to 10 mm, various shapes of parts can be formed with high dimensional accuracy by, for example, press working or punching.

[0061] In this embodiment of the plastically formed copper alloy material, when a metal plating layer is present on the surface, it can connect well with other components and is particularly suitable as a material for electronic and electrical equipment components such as terminals, busbars, lead frames, and heat dissipation members.

[0062] According to this embodiment of electronic and electrical equipment components, since they are manufactured using the copper alloy plastic processed material of this embodiment, they can exhibit excellent properties as terminals, busbars, lead frames, heat dissipation members, etc.

[0063] Although embodiments of the present invention, namely a plastically formed copper alloy material and components for electronic and electrical equipment, have been described above, the present invention is not limited thereto and can be modified as appropriate without departing from the technical spirit of the invention. For example, although one example of a method for manufacturing a plastically formed copper alloy material was described in the above-described embodiment, the method for manufacturing a plastically formed copper alloy material is not limited to this embodiment, and existing manufacturing methods may be appropriately selected and used for production.

[0064] The results of the verification experiments conducted to confirm the effects of the present invention are described below.

[0065] In the melting and casting process, a copper raw material consisting of oxygen-free copper with a purity of 99.99% by mass or higher was prepared, charged into an alumina crucible, and melted in a high-frequency melting furnace under an Ar gas atmosphere. Fe and P were added to the resulting molten copper. Zn was also added as needed. These elements were added using a Cu mother alloy. This produced a molten copper alloy with the component composition shown in Table 1, which was then poured into a carbon mold to produce an ingot. The ingot size was approximately 25 mm thick x 70 mm wide x 100 mm long.

[0066] Next, as part of the homogenization and hot rolling processes, the obtained ingots were heated at 900°C for 1 hour in an Ar gas atmosphere, and then surface-machined to remove the oxide film. After the rough rolling process, an intermediate heat treatment process was carried out at the temperatures and times listed in Table 1. Furthermore, as a precipitation heat treatment process, the ingots were held at the heat treatment temperatures listed in Table 1 for a predetermined time between 2 and 24 hours. After the heat treatment, the ingots were furnace-cooled to 300°C, followed by air cooling or water cooling. Subsequently, polishing was performed to remove the oxide film formed on the surface after the heat treatment. As a finishing process, cold rolling was carried out until the thickness listed in Table 1 was achieved, and the samples were prepared for evaluation and measurement.

[0067] The following measurements were taken for the copper alloy plastic deformation materials of the present invention and comparative examples obtained: electrical conductivity, surface Vickers hardness at room temperature, surface Vickers hardness at 400°C, and surface and interior Vickers hardness in cross-section.

[0068] (Composition) The content of various elements was measured using inductively coupled plasma atomic emission spectroscopy. The measurement results are shown in Table 1.

[0069] (Conductivity) A test specimen measuring 10 mm wide x 60 mm long was taken from the sample for evaluation, and its electrical resistance was determined using the four-terminal method. The dimensions of the test specimen were measured using a micrometer, and its volume was calculated. The conductivity was then measured from the measured electrical resistivity and the calculated volume. The test specimen was taken so that its longitudinal direction was parallel to the rolling direction. The measurement results are shown in Table 2.

[0070] (Surface Vickers Hardness) Vickers hardness was measured with a test load of 0.98 N in accordance with the micro-Vickers hardness test method specified in JIS Z 2244. The measurement surface was the surface (rolled surface). The evaluation results are shown in Table 2.

[0071] (Vickers hardness of the surface at 400°C) In accordance with the micro-Vickers hardness test method specified in JIS Z 2255, the Vickers hardness was measured with a test load of 0.98 N while the material was heated and held at 400°C. The measurement surface was the surface (rolled surface). The evaluation results are shown in Table 2.

[0072] (Vickers hardness of the cross-section) The Vickers hardness of the sample used for evaluation measurement was measured in a cross-section parallel to the rolling direction, in accordance with the micro-Vickers hardness test method specified in JIS Z 2244, with a test load of 0.98 N. "Vickers hardness of the surface layer H Ｓ "The Vickers hardness of the interior is measured in the area from the surface up to 25% of the thickness." Ｉ The measurement was taken in a region representing 25% of the thickness, centered on the thickness's core. The measurement results are shown in Table 2.

[0073]

[0074]

[0075]

[0076]

[0077] In Comparative Example 1, no Fe or P was added, and the surface Vickers hardness at room temperature was less than 130 HV, and the surface Vickers hardness at 400°C was less than 40 HV. In Comparative Example 2, the Fe content was less than 0.08% by mass, the conductivity was less than 75% IACS, and the surface Vickers hardness at 400°C was less than 40 HV. In Comparative Example 3, the Fe content exceeded 0.17% by mass, the conductivity was less than 75% IACS, and the surface Vickers hardness at 400°C was less than 40 HV. In Comparative Example 4, the P content was less than 0.025% by mass, the conductivity was less than 75% IACS, and the surface Vickers hardness at 400°C was less than 40 HV. In Comparative Example 5, the P content exceeded 0.06% by mass, and the conductivity was less than 75% IACS.

[0078] In Comparative Example 6, the precipitation heat treatment was performed at less than 400°C, resulting in an electrical conductivity of less than 75% IACS. In Comparative Example 7, the precipitation heat treatment was performed at more than 450°C, resulting in a surface Vickers hardness of less than 40 HV at 400°C. In Comparative Example 8, the finishing process was performed at less than 50%, resulting in a surface Vickers hardness of less than 130 HV at room temperature and a surface Vickers hardness of less than 40 HV at 400°C. In Comparative Example 9, the finishing process was performed at more than 95%, resulting in a surface Vickers hardness of less than 40 HV at 400°C. In Comparative Example 10, the surface Vickers hardness at room temperature was less than 130 HV, and the surface Vickers hardness at 400°C was less than 40 HV. In Comparative Example 11, the surface Vickers hardness at 400°C was less than 40 HV.

[0079] In contrast, in Examples 1 to 15 of the present invention, the conductivity was 75% IACS or higher, the surface Vickers hardness at room temperature was 130 HV or higher, and the surface Vickers hardness at 400°C was 40 HV or higher.

[0080] As described above, it has been confirmed that, according to the present invention, it is possible to provide a copper alloy plastic processed material that has excellent conductivity and hardness, and can suppress deformation even when a load is applied at high temperatures, without adding large amounts of elements other than Fe and P, and electrical and electronic equipment components made from this copper alloy plastic processed material.

Claims

1. A copper alloy plastically deformable material characterized by having a composition in which the Fe content is in the range of 0.08% by mass or more and 0.17% by mass or less, the P content is in the range of 0.025% by mass or more and 0.06% by mass or less, with the remainder being Cu and unavoidable impurities, having an electrical conductivity of 75% IACS or more, a surface Vickers hardness of 130 HV or more at room temperature, and a surface Vickers hardness of 40 HV or more at 400°C.

2. The copper alloy plastic workpiece according to claim 1, further characterized by containing Zn in a range of 0.005% by mass or more and 0.1% by mass or less.

3. Vickers hardness H of the surface layer in cross-section Ｓ and internal Vickers hardness H Ｉ All of these have a Vickers hardness of 130 HV or higher, and the surface Vickers hardness is H Ｓ and internal Vickers hardness H Ｉ Ratio H Ｓ / H Ｉ The copper alloy plastically deformed material according to claim 1, characterized in that the ratio is 0.95 or higher.

4. The copper alloy plastically deformed material according to claim 1, characterized in that it is a rolled sheet with a thickness in the range of 0.1 mm to 10 mm.

5. The copper alloy plastic workpiece according to claim 1, characterized in that it has a metal plating layer on its surface.

6. An electronic / electrical equipment component characterized by being made of a copper alloy plastically processed material as described in any one of claims 1 to 5.

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