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 both a surface heatproof temperature TS and an internal heatproof temperature TI of 450°C or higher, with the ratio TI / TS of the surface heatproof temperature TS and the internal heatproof temperature TI being 0.95 or greater.

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. 2024-232551, 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, because these components 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, due to the increased performance and miniaturization of electronic and electrical equipment components, they are molded into complex shapes, requiring 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. In addition, the manufacturing process of 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. For this reason, high heat resistance is also required for copper materials. Note that if the copper material exhibits high heat resistance at a heating temperature of 400°C, deformation can be sufficiently suppressed.

[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 the conductivity. Furthermore, there was the problem that adding elements other than Fe and P would increase manufacturing costs. In addition, when the hardness was high, there was a problem that deformation would occur when complex molding processes were performed. 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 larger this difference becomes, resulting in deformation when molding processes are performed. Furthermore, due to the difference in the structure of the surface and the interior, the heat resistance temperature of the surface and the interior differs, which leads to problems such as deformation when both heat and load are applied in the joining process, deformation during the assembly process of parts, handling, and vibration during use.

[0007] The present invention has been made in view of the circumstances described above, and aims to provide a copper alloy plastic workable material that has excellent conductivity and hardness, a uniform structure, and can suppress deformation during joining, processing, and handling, without adding large amounts of elements other than Fe and P, and electrical and electronic equipment components made from this copper alloy plastic workable material.

[0008] In order to solve the above problems, the copper alloy wrought material of Aspect 1 of the present invention has a composition in which the content of Fe is in the range of 0.08% by mass or more and 0.17% by mass or less, the content of P is in the range of 0.025% by mass or more and 0.06% by mass or less, and the balance is Cu and inevitable impurities, the conductivity is 75% IACS or more, and the Vickers hardness of the surface at room temperature is 130 HV or more, and the heat-resistant temperature T Ｓ of the surface layer and the heat-resistant temperature T Ｉ of the interior are 450 °C or higher, and the ratio T Ｓ of the heat-resistant temperature T Ｉ of the surface layer to the heat-resistant temperature T Ｉ / T Ｓ of the interior is 0.95 or higher. The heat-resistant temperature in the present invention is measured in accordance with JCBA T325:2013.

[0009] According to the copper alloy wrought material of Aspect 1 of the present invention, since the content of Fe is in the range of 0.08% by mass or more and 0.17% by mass or less, the content of P is in the range of 0.025% by mass or more and 0.06% by mass or less, and the balance is Cu and inevitable impurities, intermetallic compounds such as Fe or Fe-P precipitate in the copper matrix phase, so that the strength can be improved while maintaining excellent electrical conductivity and thermal conductivity.

[0010] Specifically, since the conductivity is 75% IACS or more, the electrical conductivity and thermal conductivity are sufficiently excellent. Also, since the Vickers hardness of the surface at room temperature is 13 + 0 HV or more, deformation during processing can be suppressed, and processing can be performed with good dimensional accuracy. And the heat-resistant temperature T Ｓ of the surface layer and the heat-resistant temperature T Ｉ of the interior are 450 °C or higher, and the ratio T Ｓ of the heat-resistant temperature T Ｉ of the surface layer to the heat-resistant temperature T Ｉ / T Ｓ of the interior is 0.95 or higher, so the heat-resistant temperature is uniform between the surface layer and the interior of the copper alloy wrought material and the structure is homogenized, and deformation during joining, processing, and handling can be suppressed.

[0011] 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.

[0012] 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 surface Vickers hardness H of the copper alloy plastic workpiece after heat treatment held at 400°C for 5 minutes is 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 Ｉ / H Ｓ It is characterized by having a Vickers hardness of 0.95 or higher. According to the copper alloy plastically deformed material of embodiment 3 of the present invention, the Vickers hardness of the surface layer after heat treatment held at 400°C for 5 minutes is 0.95 or higher. 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 Ｉ / H Ｓ Since the hardness is set at 0.95 or higher, it remains sufficiently hard even after heat treatment, and the hardness is uniform throughout, further suppressing deformation during joining, processing, and handling.

[0013] The copper alloy plastically formed material of aspect 4 of the present invention is characterized in that it is a rolled sheet with a thickness in the range of 0.1 mm to 10 mm, in any one of the copper alloy plastically formed materials of aspects 1 to 3 of the present invention. According to the copper alloy plastically formed material of aspect 4 of the present invention, since it is a rolled sheet with 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, punching.

[0014] The copper alloy plastic workpiece of aspect 5 of the present invention is characterized by having a metal plating layer on its surface, in addition to being a copper alloy plastic workpiece of any one of aspects 1 to 4 of the present invention. The copper alloy plastic workpiece of aspect 5 of the present invention is particularly suitable as a material for electronic and electrical equipment components such as terminals, busbars, lead frames, and heat dissipation members because it has a metal plating layer on its surface.

[0015] The component for electronic and electrical equipment according to aspect 6 of the present invention is characterized by being made of a copper alloy plastic processed material according to any one of aspects 1 to 5 of the present invention. According to the component for electronic and electrical equipment according to aspect 6 of the present invention, since it is manufactured using the above-mentioned copper alloy plastic processed material, it can exhibit excellent properties as a terminal, busbar, lead frame, heat dissipation member, etc.

[0016] This makes it possible to provide a copper alloy plastic workable material that has excellent conductivity and hardness, a uniform structure, and can suppress deformation during joining, processing, and handling, without adding large amounts of elements other than Fe and P, as well as electrical and electronic equipment components made from this copper alloy plastic workable material.

[0017] This is a flowchart of the manufacturing method for the copper alloy plastically deformed material according to this embodiment.

[0018] The following describes a copper alloy plastically formed material and electrical and electronic equipment components according to one embodiment of the present invention. The copper alloy plastically formed material in this embodiment 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. In addition, the copper alloy plastically formed material in this embodiment may further contain Zn in the range of 0.005% by mass or more and 0.1% by mass or less.

[0019] Furthermore, in the plastically deformed copper alloy material of this embodiment, the electrical conductivity is 75% IACS or higher, and the surface Vickers hardness at room temperature is 130 HV or higher. In addition, in the plastically deformed copper alloy material of this embodiment, the heat resistance temperature of the surface layer is T Ｓ and internal heat resistance temperature T Ｉ The temperature is 450°C or higher, and the heat resistance temperature of the surface layer is T Ｓand internal heat resistance temperature T Ｉ T Ｉ / T Ｓ The threshold is considered to be 0.95 or higher.

[0020] In this embodiment, the Vickers hardness H of the surface layer of the copper alloy plastically deformed material after heat treatment held at 400°C for 5 minutes is Ｓ and internal Vickers hardness H Ｉ It is preferable that the voltage is 130 HV or higher.

[0021] Furthermore, in the copper alloy plastically deformed material of this embodiment, the Vickers hardness H of the surface layer after heat treatment held at 400°C for 5 minutes is Ｓ and internal Vickers hardness H Ｉ Ratio H Ｉ / H Ｓ It is preferable that the value is 0.95 or higher.

[0022] Furthermore, in the copper alloy plastically deformed material of this embodiment, it is preferable that the material is a rolled sheet with a thickness in the range of 0.1 mm to 10 mm.

[0023] Furthermore, in the copper alloy plastically deformed material of this embodiment, it is preferable to have a metal plating layer on the surface.

[0024] 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.

[0025] (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%.

[0026] 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.

[0027] (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%.

[0028] 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 0.03% 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 0.05% by mass or less.

[0029] (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, it is possible to suppress a decrease in electrical conductivity and thermal conductivity. 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.

[0030] 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.

[0031] (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.

[0032] 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.

[0033] (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.

[0034] (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.

[0035] (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.

[0036] (Heat-resistant temperature T of the surface layer Ｓ and internal heat resistance temperature T Ｉ In this embodiment of the copper alloy plastically deformed material, the heat resistance temperature of the surface layer is T Ｓ and internal heat resistance temperature TＩ The temperature is said to be 450°C or higher, and the heat resistance temperature of the surface layer is T Ｓ and internal heat resistance temperature T Ｉ T Ｉ / T Ｓ The value is set to 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. Furthermore, the heat resistance temperature in this embodiment was measured in accordance with JCBA T325:2013 "Heat resistance evaluation for lead frame applications," and the heating temperature at which the hardness decreased to 80% of the value before heating was read from the graph of the obtained isochronous softening curve.

[0037] As described above, in the copper alloy plastically deformed material of this embodiment, the heat resistance temperature of the surface layer T Ｓ and internal heat resistance temperature T Ｉ The temperature is 450°C or higher, and the heat resistance temperature of the surface layer is T Ｓ and internal heat resistance temperature T Ｉ T Ｉ / T Ｓ Since the heat resistance temperature is set to 0.95 or higher, the heat resistance temperature is uniform between the surface and interior of the plastically deformed copper alloy material, resulting in a uniform structure, which makes it possible to suppress deformation during joining, processing, and handling. Note that the heat resistance temperature of the surface layer of the plastically deformed copper alloy material in this embodiment is T Ｓ and internal heat resistance temperature T Ｉ The temperature is preferably 460°C or higher, and more preferably 470°C or higher. The heat resistance temperature of the surface layer of the plastically deformed copper alloy material is not particularly limited. Ｓ and internal heat resistance temperature T Ｉ It is effectively below 700°C. Also, the heat resistance temperature of the surface layer is T. Ｓ and internal heat resistance temperature T Ｉ T Ｉ / T Ｓ It is more preferably 0.97 or higher, and even more preferably 0.98 or higher. The heat resistance temperature of the surface layer is T. Ｓ and internal heat resistance temperature T Ｉ T Ｉ / T Ｓ The upper limit will effectively be 1.05 or less.

[0038] (Vickers hardness H of the surface layer after heat treatment held at 400°C for 5 minutes) Ｓ and internal Vickers hardness H Ｉ In this embodiment of the plastically deformed copper alloy material, the Vickers hardness of the surface layer after heat treatment held at 400°C for 5 minutes is H Ｓ and internal Vickers hardness H Ｉ It is preferable that the Vickers hardness of the surface layer H is 130 HV or higher. Also, the Vickers hardness of the surface layer after heat treatment held at 400°C for 5 minutes is preferable. Ｓ and internal Vickers hardness H Ｉ Ratio H Ｉ / H Ｓ It is preferable that the value is 0.95 or higher.

[0039] In this embodiment of the plastically deformed copper alloy material, the Vickers hardness H of the surface layer after heat treatment held at 400°C for 5 minutes is Ｓ and internal Vickers hardness H Ｉ If the Vickers hardness is 130 HV or higher, sufficient hardness is ensured throughout the entire plastically deformed copper alloy material even after heat treatment, further suppressing deformation during processing, use, and handling. Furthermore, the Vickers hardness of the surface layer after heat treatment held at 400°C for 5 minutes is HV. Ｓ and internal Vickers hardness H Ｉ Ratio H Ｉ / H Ｓ When the value is 0.95 or higher, there is no significant difference in hardness between the surface and the interior even after heat treatment, 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 after heat treatment held at 400°C for 5 minutes is measured. Ｓ and internal Vickers hardness H Ｉ It is more preferably 132 HV or higher, and more preferably 135 HV or higher. While not particularly limited, the Vickers hardness of the surface layer after heat treatment held at 400°C for 5 minutes is H. Ｓ and internal Vickers hardness H Ｉ The Vickers hardness of the surface layer after heat treatment held at 400°C for 5 minutes is H. Ｓand internal Vickers hardness H Ｉ Ratio H Ｉ / H Ｓ It is more preferably 0.97 or higher, and even more preferably 0.98 or higher. Note that the Vickers hardness H of the surface layer after heat treatment held at 400°C for 5 minutes. Ｓ and internal Vickers hardness H Ｉ Ratio H Ｉ / H Ｓ 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 step S04) After the oxide film removal step S03, rough machining is performed to process the material into a predetermined shape. Although the temperature conditions in this rough machining step are not particularly limited, in order to suppress recrystallization or improve dimensional accuracy, it is preferably within the range of -200°C to 200°C for cold or warm rolling, and room temperature is particularly preferred. Regarding the machining rate, 20% or more is preferable, and 30% or more is even more preferable. Also, regarding the machining method, there is no particular limitation, and for example, rolling, drawing, extrusion, groove rolling, forging, pressing, etc. can be adopted. In this embodiment, rolling is performed.

[0049] (Intermediate heat treatment step S05) After the rough machining step S04, intermediate heat treatment is carried out to improve workability or to obtain a recrystallized structure. In this intermediate heat treatment step S05, the heat treatment temperature is preferably within the range of 500°C or more and 800°C or less, and the holding time at the heat treatment temperature is preferably within the range of 20 seconds or more and 300 seconds or less. 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, and the mechanical properties within the material will become non-uniform in the finishing machining step S07, resulting in deformation when performing forming machining. As a result, the surface heat resistance temperature T Ｓ and the internal heat resistance temperature T Ｉ will be less than 450°C, and the ratio T Ｓ of the surface heat resistance temperature T Ｉ to the internal heat resistance temperature T Ｉ / T Ｓ may be less than 0.95.

[0050] (Precipitation heat treatment step S06) After the intermediate heat treatment step S05, precipitation heat treatment is performed to precipitate intermetallic compound particles such as Fe or Fe-P in the copper matrix phase. If the heat treatment temperature in this precipitation heat treatment step S06 is less than 400°C, sufficient intermetallic compound particles such as Fe or Fe-P cannot be precipitated, the conductivity is less than 75% IACS, the surface Vickers hardness at room temperature is less than 130 HV, and the surface Vickers hardness H Ｓ and the internal Vickers hardness H ＩThe Vickers hardness may fall below 130 HV. On the other hand, if the heat treatment temperature in the precipitation heat treatment step S07 exceeds 450°C, the heat resistance temperature will fall below 450°C, and the Vickers hardness of the heat treatment held at 400°C for 5 minutes may fall below 130 HV. 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 surface Vickers hardness may be low. On the other hand, if the processing rate in the finishing process S07 exceeds 95%, the heat resistance temperature of the surface layer and the heat resistance temperature of the interior will both be less than 450°C, and the Vickers hardness of the heat treatment held at 400°C for 5 minutes may be less than 130HV. 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 Relief Heat Treatment Step S08) As necessary, strain relief heat treatment may be performed for the purpose of removing residual strain generated in the finishing process step S07. The heat treatment temperature in the strain relief heat treatment step S08 is preferably in the range of 200°C or higher and 700°C or lower, and the holding time at the heat treatment temperature is preferably in the range of 1 second or longer and 24 hours or shorter. When performing heat treatment at a high temperature, it is preferable to shorten the holding time, and when performing heat treatment at a low temperature, it is preferable to lengthen the holding time.

[0055] Through the above steps, the copper alloy wrought material of the present embodiment will be produced. Note that a plating process step for forming a metal plating layer may be performed. Further, the component for electronic and electrical equipment of the present embodiment is manufactured by subjecting the above-described copper alloy wrought material to press working, punching, bending, etc.

[0056] According to the copper alloy wrought material of the present embodiment configured as described above, since 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 composed of Cu and inevitable impurities, by precipitating intermetallic compounds such as Fe or Fe-P in the copper matrix phase in the precipitation heat treatment step S06, the strength can be improved while maintaining excellent electrical conductivity and thermal conductivity.

[0057] Further, since the conductivity is 75% IACS or higher, the electrical conductivity and thermal conductivity are sufficiently excellent. Furthermore, since the Vickers hardness of the surface at room temperature is 130 HV or higher, deformation during processing can be suppressed, and processing can be performed with good dimensional accuracy. And the heat resistance temperature T Ｓ of the surface layer and the heat resistance temperature T Ｉ of the interior are 450°C or higher, and the ratio T Ｓ of the heat resistance temperature T Ｉ of the surface layer to the heat resistance temperature T Ｉ of the interior is 0.95 or higher, so the heat resistance temperature is uniform between the surface layer and the interior of the copper alloy wrought material and the structure is homogenized, making it possible to suppress deformation during joining, processing, and handling.

[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 after heat treatment held at 400°C for 5 minutes is 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 Ｉ / H Ｓ When the hardness is set to 0.95 or higher, the material remains sufficiently hard even after heat treatment, and the hardness is uniform throughout, further suppressing deformation during joining, processing, and handling.

[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: electrical conductivity, surface Vickers hardness at room temperature, heat resistance temperature of the surface and interior, and surface and interior Vickers hardness after heat treatment held at 400°C for 5 minutes.

[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] (Heat resistance temperature) The heat resistance temperature of the surface layer is T in accordance with JCBA T325:2013. Ｓ and internal heat resistance temperature T Ｉ The heat resistance temperature of the surface layer was measured. Ｓ The measurement was taken in the area from the surface up to 25% of the thickness, and the internal heat resistance temperature T Ｉ The measurement was taken in a region representing 25% of the thickness, centered on the thickness center. The evaluation results are shown in Table 2.

[0072] (Vickers hardness after heat treatment held at 400°C for 5 minutes) A ​​sample for evaluation measurement was placed in a heat treatment furnace and subjected to heat treatment at 400°C for 5 minutes in an inert gas atmosphere, followed by water cooling. The Vickers hardness of the heat-treated sample 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, Fe and P were not added, the surface Vickers hardness at room temperature was less than 130 HV, and the heat resistance temperature of the surface layer was T Ｓ and internal heat resistance temperature T Ｉ The temperature was less than 450°C. In Comparative Example 2, the Fe content was less than 0.08% by mass, the conductivity was less than 75% IACS, and the heat resistance temperature of the surface layer was less than 450°C. Ｓ and internal heat resistance temperature T Ｉ The temperature was less than 450°C. In Comparative Example 3, the Fe content exceeded 0.17% by mass, and the conductivity was less than 75% IACS.

[0078] In Comparative Example 4, the P content was less than 0.01% by mass, the conductivity was less than 75% IACS, and the heat resistance temperature of the surface layer was T Ｓ and internal heat resistance temperature T Ｉ The temperature was less than 450°C. In Comparative Example 5, the P content exceeded 0.07% by mass, and the conductivity was less than 75% IACS.

[0079] In Comparative Example 6, the precipitation heat treatment was performed at a temperature of 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 a temperature exceeding 450°C, resulting in a surface layer heat resistance temperature T Ｓ and internal heat resistance temperature T Ｉ The temperature was less than 450°C. In Comparative Example 8, the finishing process was less than 50%, and the surface Vickers hardness at room temperature was less than 130 HV. In Comparative Example 9, the finishing process was more than 95%, and the heat resistance temperature of the surface layer was less than 450°C. Ｓ and internal heat resistance temperature T Ｉ The temperature fell below 450°C.

[0080] In Comparative Example 10, the internal heat resistance temperature T Ｉ The temperature becomes less than 450°C, and the heat resistance temperature of the surface layer T Ｓ and internal heat resistance temperature T Ｉ T Ｉ / T Ｓ The value was less than 0.95. In Comparative Example 11, the heat resistance temperature of the surface layer T Ｓ and internal heat resistance temperature T Ｉ The temperature is less than 450°C, and the heat resistance temperature of the surface layer is T Ｓ and internal heat resistance temperature T ＩT Ｉ / T Ｓ The value fell below 0.95.

[0081] In contrast, in Examples 1 to 15 of the present invention, the conductivity is 75% IACS or higher, the surface Vickers hardness at room temperature is 130 HV or higher, and the heat resistance temperature of the surface layer is T Ｓ and internal heat resistance temperature T Ｉ The temperature is 450°C or higher, and the heat resistance temperature of the surface layer is T Ｓ and internal heat resistance temperature T Ｉ T Ｉ / T Ｓ The value was 0.95 or higher.

[0082] As described above, it has been confirmed that, according to the present invention, it is possible to provide a copper alloy plastic workable material that has excellent conductivity and hardness, a uniform structure, and can suppress deformation during joining, processing, and handling, without adding large amounts of elements other than Fe and P, as well as electrical and electronic equipment components made from this copper alloy plastic workable material.

Claims

1. The composition has an Fe content of 0.08% to 0.17% by mass, a P content of 0.025% to 0.06% by mass, with the remainder being Cu and unavoidable impurities, an electrical conductivity of 75% IACS or higher, a surface Vickers hardness of 130 HV or higher at room temperature, and a surface heat resistance temperature T Ｓ and internal heat resistance temperature T Ｉ Each of these is 450°C or higher, and the heat resistance temperature of the surface layer is T Ｓ and internal heat resistance temperature T Ｉ T Ｉ / T Ｓ A copper alloy plastically deformable material characterized by having a coefficient of 0.95 or higher.

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 after heat treatment at 400°C for 5 minutes Ｓ and Vickers hardness H of the interior Ｉ are 130 HV or more, and the ratio H Ｓ of the Vickers hardness H of the surface layer Ｉ to the Vickers hardness H of the interior Ｉ is 0.95 or more, the copper alloy wrought material according to claim 1, characterized by this. Ｓ ​ 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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