COPPER ALLOY AND MANUFACTURING METHOD THEREOF

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Taiwan Application Serial Number 113144944, filed Nov. 21, 2024, which is herein incorporated by reference in its entirety.

BACKGROUND

Field of Invention

The present disclosure relates to a copper alloy and a manufacturing method thereof. More particularly, the present disclosure relates to the copper alloy having a high tensile strength, a high heat transfer coefficient, and a high electrical conductivity, and the manufacturing method thereof.

Description of Related Art

In light of the global trend toward energy conservation and carbon reduction, charging devices have been widely used in many fields. Therefore, issues such as improving charging power and thermal management are highly regarded by related industries.

For example, in the field of electric vehicle, if the thermal conductivity of the charging terminal materials of charging plugs is poor, the accumulated heat energy converted from the power loss caused by resistance during high-power charging will further cause the charging plugs to be heated up excessively, making it unsuitable for use in the fields of connectors and heat sinks.

Furthermore, due to the temperature rise effect, the aforementioned connectors and heat sinks are also prone to risks of exceeding the safe operating temperature range, as well as potential fire hazards.

In view of the above, there is a need to develop a copper alloy and a manufacturing method thereof to overcome the above problems.

SUMMARY

The manufacturing method of the copper alloy of the present disclosure utilizes an initial copper billet containing silicon and iron to enhance the heat transfer coefficient and the electrical conductivity of the obtained copper alloy. Also, a precipitation and refinement processing is performed to precipitate the Fe₃Si precipitate phase and strengthen the alloy grain boundaries, thereby enhancing the tensile strength of the copper alloy.

At least one example of the present disclosure provides a manufacturing method of a copper alloy. The manufacturing method includes the following steps. An initial copper billet is provided, wherein based on a total weight of the initial copper billet as 100 weight percent, the initial copper billet includes 9.6 weight percent to 10.4 weight percent of iron, 0.3 weight percent to 0.5 weight percent of silicon, a remaining weight percent of copper, and inevitable impurities. The initial copper billet is heated to homogenize the initial copper billet, so as to obtain a homogeneous copper billet. The homogeneous copper billet is subjected to a precipitation and refinement processing such that the homogeneous copper billet produces a precipitate including Fe₃Si precipitate phase, so as to obtain the copper alloy, wherein a radius of the precipitate is less than 30 nm, and a mean grain size of the copper alloy is less than 700 nm.

In at least one example of the present disclosure, the initial copper billet is free from nickel and rare earth elements.

In at least one example of the present disclosure, the initial copper billet is free from beryllium and cobalt elements.

In at least one example of the present disclosure, the initial copper billet is free from manganese element.

In at least one example of the present disclosure, the initial copper billet is free from magnesium element.

In at least one example of the present disclosure, the initial copper billet includes 9.73 weight percent to 10.31 weight percent of iron.

In at least one example of the present disclosure, the initial copper billet includes 0.32 weight percent to 0.47 weight percent of silicon.

In at least one example of the present disclosure, a heating temperature in a step of heating the initial copper billet is 900° C. to 940° C., and a heating temperature holding time in the step of heating the initial copper billet is 4 hours to 6 hours.

In at least one example of the present disclosure, the precipitation and refinement processing includes the following steps. The above-mentioned homogeneous copper billet is quenched, so as to obtain a quenched copper billet, wherein a step of quenching the homogeneous copper billet causes the homogeneous copper billet to begin to precipitate the Fe₃Si precipitate phase.

The above-mentioned quenched copper billet is rolled, so as to obtain a rolled copper, wherein a step of rolling the quenched copper billet causes the quenched copper billet to continuously precipitate the Fe₃Si precipitate phase and refine the Fe₃Si precipitate phase. The above-mentioned rolled copper is aged, so as to obtain the copper alloy, wherein a step of aging the rolled copper causes the rolled copper to continuously precipitate the Fe₃Si precipitate phase.

In at least one example of the present disclosure, the quenching is performed by water quenching.

In at least one example of the present disclosure, the step of rolling the above-mentioned quenched copper billet further includes the following steps. The above-mentioned quenched copper billet is hot rolled, so as to obtain a hot-rolled copper. The above-mentioned hot-rolled copper is cold rolled, so as to obtain the rolled copper.

In at least one example of the present disclosure, a hot rolling temperature in a step of hot rolling the above-mentioned quenched copper billet is 900° C. to 930° C., and a hot-rolling reduction ratio in the step of hot rolling the above-mentioned quenched copper billet is at least 60%.

In at least one example of the present disclosure, a cold-rolling reduction ratio in a step of cold rolling the above-mentioned hot-rolled copper is at least 90%.

In at least one example of the present disclosure, the cold rolling is performed at room temperature.

In at least one example of the present disclosure, an aging temperature in the step of aging the above-mentioned rolled copper is 450° C. to 500° C., and an aging temperature holding time in the step of aging the above-mentioned rolled copper is 3 hours to 4 hours.

At least one example of the present disclosure provides a copper alloy made by the above-mentioned manufacturing method, wherein a tensile strength of the copper alloy is greater than or equal to 520 MPa, and a heat transfer coefficient of the copper alloy is greater than or equal to 290 W/m·K.

In at least one example of the present disclosure, an electrical conductivity of the copper alloy is greater than or equal to 57% IACS.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure can be more fully understood by reading the following detailed description of the embodiments, with reference made to the accompanying drawings.

FIG. 1 is a flow chart of a manufacturing method of a copper alloy according to some embodiments of the present disclosure.

FIG. 2A was a micrograph under a field emission transmission electron microscope of Experimental Example 2 according to the present disclosure.

FIG. 2B was a distribution graph of the iron element in the block of FIG. 2A.

FIG. 2C was a distribution graph of the silicon element in the block of FIG. 2A

DETAILED DESCRIPTION

The manufactures and uses of embodiments of the present disclosure are discussed in detail below. However, it is to be understood that the embodiments provide many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are illustrative only and are not intended to limit the scope of the present disclosure.

In the present disclosure, the range expressed by “one value to another value” is a summary expression that avoids enumerating all the values in the range one by one in the specification. Therefore, the description of a specific range covers any value within that numerical range and a smaller numerical range bounded by any numerical value within that numerical range. It is the same as the arbitrary numerical value and the smaller numerical range is expressly written in the specification.

Currently, a copper alloy including rare earth elements is known. However, the tensile strength of this copper alloy is only between 280 MPa and 330 MPa, making it unsuitable for connector applications. Furthermore, rare earth elements are not only expensive but also strategic materials, making them difficult to obtain.

Currently, a bimetallic composite material including a copper alloy plate and a steel plate is known. However, the heat transfer coefficient of this bimetallic composite material is only between 220 W/m·K and 230 W/m·K, making it unsuitable for applications in connectors and heat sinks.

Currently, a bronze alloy containing beryllium is known. However, beryllium in the bronze alloy is toxic, so many countries have begun to legislate to restrict its use. Furthermore, this bronze alloy is not in line with the trend of future sustainable development.

FIG. 1 is a flow chart of a manufacturing method 100 of a copper alloy according to some embodiments of the present disclosure. An initial copper billet is provided, as shown in a step 110 of FIG. 1. Based on a total weight of the initial copper billet as 100 weight percent, the initial copper billet includes 9.6 weight percent to 10.4 weight percent of iron, 0.3 weight percent to 0.5 weight percent of silicon, a remaining weight percent of copper, and inevitable impurities. It should be noted that the “inevitable impurities” mentioned herein can be trace elements such as phosphorus, sulfur, tin, or zinc without additional addition of the above trace elements. Because the initial copper billet of the present disclosure mainly includes copper, iron, and silicon, the disclosed copper alloy may also be referred to as “copper-iron-silicon alloy (Cu—Fe—Si).”

In some embodiments, the initial copper billet includes 9.8, 10, or 10.2 weight percent of iron. In some embodiments, the initial copper billet includes 0.35, 0.4, or 0.45 weight percent of silicon. Silicon will form a Fe₃Si precipitate phase with iron. In other words, the silicon element promotes the iron precipitate in the copper matrix, thereby reducing the residual iron element in the copper matrix and increasing the purity of the copper matrix. As a result, the heat transfer coefficient and the electrical conductivity of the obtained copper alloy are enhanced. Specifically, because the heat transfer coefficient and the electrical conductivity of copper are better than those of iron, the precipitate of the Fe₃Si precipitate phase in the copper billet is beneficial to enhancing the heat transfer coefficient and the electrical conductivity of the obtained copper alloy.

If a content of iron of the initial copper billet was less than 9.6 weight percent and/or a content of silicon of the initial copper billet was less than 0.3 weight percent, the subsequent precipitate of the Fe₃Si precipitate phase would be insufficient, thereby failing to form the disclosed copper alloy having the high heat transfer coefficient and the high electrical conductivity. If the content of iron of the initial copper billet was greater than 10.4 weight percent and/or the content of silicon of the of the initial copper billet was greater than 0.5 weight percent, the heat transfer coefficient and the electrical conductivity of the subsequently obtained copper alloy would be poor.

It is worth noting that the above-mentioned initial copper billet is free from (excludes) nickel and rare earth elements. Therefore, compared to conventional copper alloy containing the rare earth elements, the disclosed copper alloy has a lower manufacturing cost. In some embodiments, the initial copper billet is free from (excludes) beryllium and/or cobalt elements. Therefore, compared to conventional copper alloy containing the beryllium element, the disclosed copper alloy meets the trend of future sustainable development. In some embodiments, the initial copper billet is free from (excludes) manganese element. In some embodiments, the initial copper billet is free from (excludes) magnesium element.

After the step 110, the initial copper billet is heated to homogenize the initial copper billet, so as to obtain a homogeneous copper billet, as shown in a step 120 of FIG. 1. The purpose of homogenization is to make copper, iron, and silicon alloy elements redistribute evenly within the copper billet through high-temperature diffusion, which is beneficial to the subsequent precipitation and refinement processing.

In some specific examples, a heating temperature in the step of heating the above-mentioned initial copper billet may be selectively 900° C. to 940° C., for example, 910° C., 920° C., or 930° C., but is not limited thereto. If the heating temperature was less than 900° C., the microstructure of the homogeneous copper billet may be uneven, thereby failing to form the disclosed copper alloy having the specific tensile strength, the specific heat transfer coefficient, and the specific electrical conductivity. If the heating temperature was greater than 940° C., there is no beneficial effect on forming the disclosed copper alloy. Therefore, when the heating temperature is in the above range, it is beneficial to forming the disclosed copper alloy having the specific tensile strength, the specific heat transfer coefficient, and the specific electrical conductivity.

In some specific examples, a heating temperature holding time in the step of heating the above-mentioned initial copper billet may be selectively 4 hours to 6 hours, for example, 5 hours, but is not limited thereto. If the heating temperature holding time was less than 4 hours, the microstructure of the homogeneous copper billet may be uneven, thereby failing to form the disclosed copper alloy having the specific tensile strength, the specific heat transfer coefficient, and the specific electrical conductivity. If the heating temperature holding time was greater than 6 hours, there is no beneficial effect on forming the disclosed copper alloy. Therefore, when the heating temperature holding time is in the above range, it is beneficial to forming the disclosed copper alloy having the specific tensile strength, the specific heat transfer coefficient, and the specific electrical conductivity.

After the step 120, the above-mentioned homogeneous copper billet is subjected to a precipitation and refinement processing such that the homogeneous copper billet produces a precipitate including the Fe₃Si precipitate phase, so as to obtain the copper alloy, as shown in a step 130 and a step 140 of FIG. 1. In the present examples, the precipitate of the copper alloy includes the Fe₃Si precipitate phase and other Fe precipitate phase. A radius of the Fe precipitate phase is greater than a radius of the Fe₃Si precipitate phase. In some specific examples, the radius of the precipitates (i.e., the Fe₃Si precipitate phase and the other Fe precipitate phase) of the copper alloy is less than 30 nm. In some specific examples, a mean grain size of the copper alloy is less than 700 nm. The “mean grain size” refers to the average radius of the grains excluding the precipitates (the Fe₃Si precipitate phase and the other Fe precipitate phase).

The step 130 includes the steps 132, 134, and 136. After the step 120, the above-mentioned homogeneous copper billet is quenched, as shown in the step 132 of FIG. 1. The quenching step cools the hot homogeneous copper billet to room temperature. In some specific examples, the quenching is performed by water quenching. The quenching step causes the homogeneous copper billet to begin to precipitate the Fe₃Si precipitate phase, which is beneficial to enhancing the heat transfer coefficient and the electrical conductivity of the obtained copper alloy.

After the step 132, the above-mentioned quenched copper billet is rolled, so as to obtain a rolled copper, as shown in the step 134 of FIG. 1. The rolling step causes the quenched copper billet to continuously precipitate the Fe₃Si precipitate phase and refine (fragment) the Fe₃Si precipitate phase. In other words, the radius of the Fe₃Si precipitate phase of the quenched copper billet is greater than the radius of the Fe₃Si precipitate phase of the rolled copper. The refinement (smaller in size) of the Fe₃Si precipitate phase is beneficial to enhancing the mechanical strength (such as, tensile strength) of the copper alloy.

In some embodiments, the step of rolling the above-mentioned quenched copper billet further includes the following steps. The above-mentioned quenched copper billet is hot rolled, so as to obtain a hot-rolled copper; and the above-mentioned hot-rolled copper is cold rolled, so as to obtain a rolled copper. Specifically, during the hot rolling step, the microstructure of the quenched copper billet is deformed, so that the Fe₃Si precipitate phase in the quenched copper billet is continuously precipitated and refined. During the cold rolling step, the Fe₃Si precipitate phase in the hot-rolled copper can be further refined.

In some specific examples, a hot rolling temperature in the step of hot rolling the above-mentioned quenched copper billet may be selectively 900° C. to 930° C., for example, 910° C. or 920° C., but is not limited thereto. In some specific examples, a hot-rolling reduction ratio in the step of hot rolling the above-mentioned quenched copper billet may be selectively 60%, for example, 65%, 70%, or 75%, but is not limited thereto. When the hot rolling temperature and the hot-rolling reduction ratio are in the above-mentioned ranges and conditions, it is beneficial to forming the disclosed copper alloy having the specific tensile strength, the specific heat transfer coefficient, and the specific electrical conductivity.

The disclosed cold rolling step is performed at room temperature. The cold rolling step can not only refine the Fe₃Si precipitate phase in the hot-rolled copper, but also enhance the dispersibility of the Fe₃Si precipitate phase. Therefore, the cold rolling step is beneficial to strengthening the mechanical strength of the copper alloy. In some specific examples, a cold-rolling reduction ratio in the step of cold rolling the above-mentioned hot-rolled copper may be selectively at least 90%, for example, 92%, 94%, or 96%, but is not limited thereto. When the cold-rolling reduction ratio is in the above-mentioned range, it is beneficial to forming the disclosed copper alloy having the specific tensile strength, the specific heat transfer coefficient, and the specific electrical conductivity.

After the step 134, the above-mentioned rolled copper is aged, so as to obtain the disclosed copper alloy, as shown in the step 136 of FIG. 1. The aging step causes the rolled copper to continuously precipitate the Fe₃Si precipitate phase.

In some specific examples, an aging temperature in the step of aging the above-mentioned rolled copper may be selectively 450° C. to 500° C., for example, 460° C., 470° C., 480° C., or 490° C., but is not limited thereto. In some specific examples, an aging temperature holding time in the step of aging the above-mentioned rolled copper may be selectively 3 hours to 4 hours, for example, 3.5 hours, but is not limited thereto. When the aging temperature and the aging temperature holding time are in the above-mentioned ranges, it is beneficial to forming the disclosed copper alloy having the specific tensile strength, the specific heat transfer coefficient, and the specific electrical conductivity.

The step 134 (the rolling step) and the step 136 (the aging step) in the method 100 can precipitate (refine) the Fe₃Si precipitate phase and produce a grain boundary strengthening effect, which is beneficial to obtaining the copper alloy having the specific tensile strength.

In the present examples, the tensile strength of the copper alloy made by the above-mentioned manufacturing method is greater than or equal to 520 MPa, for example, 530 MPa or 540 MPa. In some specific examples, the heat transfer coefficient of the copper alloy is greater than or equal to 290 W/m·K, for example, 300 W/m·K or 310 W/m·K. In some specific examples, the electrical conductivity of the copper alloy is greater than or equal to 57% IACS (International Annealed Copper Standard), for example, 60% IACS or 62% IACS.

In the present disclosure, the effects of precipitation strengthening and grain boundary strengthening are achieved by adding silicon and iron elements in the initial copper billet and various process steps, thereby enhancing the tensile strength, the heat transfer coefficient, and the electrical conductivity of the copper alloy. Specifically, in the disclosed manufacturing method of the copper alloy, the Fe₃Si precipitate phase is continuously refined so that the radius of the Fe₃Si precipitate phase becomes smaller and smaller, thereby achieving the effects of precipitation strengthening and grain boundary strengthening. The disclosed copper alloy has good tensile strength, good heat transfer coefficient, and good electrical conductivity, which is beneficial for subsequent applications, for example, application in the fields of connectors and heat sinks, but is not limited thereto.

In the electric vehicle field, the copper alloy of the present disclosure can be used as terminal materials for charging plugs, connectors, and heat sinks. The copper alloy of the present disclosure has a good heat transfer coefficient, effectively reduces heat accumulation, improves usage safety, and increases charging stability.

The following Experimental Examples and Comparative Example are used to describe the applications of the present disclosure, but they are not intended to limit the present disclosure. Those skilled in the art may make various changes and alterations herein without departing from the spirit and scope of the present disclosure.

EXPERIMENTAL EXAMPLE 1

In Experimental Example 1, based on a total weight of the initial copper billet as 100 weight percent, the initial copper billet included 10.31 weight percent of iron, 0.32 weight percent of silicon, a remaining weight percent of copper, and inevitable impurities. The initial copper billet composition of Experimental Example 1 was shown in Table 1 below.

TABLE 1
Composition
(weight percent)	Fe	Si	Cu

Experimental Example 1	10.31	0.32	remaining weight
(Cu—Fe—Si)			percent
Experimental Example 2	9.73	0.35	remaining weight
(Cu—Fe—Si)			percent
Experimental Example 3	9.91	0.47	remaining weight
(Cu—Fe—Si)			percent
Comparative Example 1	9.68	no addition	remaining weight
(Cu—Fe)			percent

In Experimental Example 1, the initial copper billet was heated to homogenize the initial copper billet, so as to obtain the homogeneous copper billet, wherein the heating temperature was 900° C. and the heating temperature holding time was 5 hours. Then, the above-mentioned homogeneous copper billet was subjected to the precipitation and refinement processing, wherein the precipitation and refinement processing included quenching the above-mentioned homogeneous copper billet to cool it to room temperature, so as to obtain the quenched copper billet. Next, the above-mentioned quenched copper billet was rolled to obtain the rolled copper. In the step of rolling the above-mentioned quenched copper billet, it included hot rolling the above-mentioned quenched copper billet to obtain the hot-rolled copper, and cold rolling the above-mentioned hot-rolled copper at room temperature to obtain the rolled copper, wherein the hot rolling temperature was 900° C., the hot-rolling reduction ratio was 60%, and the cold-rolling reduction ratio was 90%. Thereafter, the above-mentioned rolled copper was aged, so as to obtain the copper alloy of Experimental Example 1, wherein the aging temperature was 450° C. and the aging temperature holding time was 3 hours.

The evaluation results of the copper alloy of Experimental Example 1 were shown in Table 2 below. The tensile strength was 543.7 MPa, the heat transfer coefficient was 290.2 W/m·K, and the electrical conductivity was 57.6% IACS.

	TABLE 2
	Tensile	Heat transfer	Electrical
	strength	coefficient	conductivity
	(MPa)	(W/m · K)	(% IACS)

	Experimental	543.7	290.2	57.6
	Example 1
	(Cu—Fe—Si)
	Experimental	528.2	304.0	60.7
	Example 2
	(Cu—Fe—Si)
	Experimental	522.5	309.2	62.4
	Example 3
	(Cu—Fe—Si)
	Comparative	474.1	265.3	54.8
	Example 1
	(Cu—Fe)

EXPERIMENTAL EXAMPLE 2 AND EXPERIMENTAL EXAMPLE 3

The initial copper billet compositions of Experimental Example 2 and Experimental Example 3 were shown in Table 1 above. The process conditions for the copper alloys of Experimental Example 2 and Experimental Example 3 were the same as those of Experimental Example 1. The evaluation results of the copper alloys of Experimental Example 2 and Experimental Example 3 were shown in Table 2 above.

FIG. 2A was a micrograph 210 under a field emission transmission electron microscope (FETEM) of Experimental Example 2 according to the present disclosure. FIG. 2B was a distribution graph 220 of the iron element in the block 212 of FIG. 2A. FIG. 2C was a distribution graph 230 of the silicon element in the block 212 of FIG. 2A.

It could be known from the distribution graph 220 of the iron element and distribution graph 230 of the silicon element that the distributions of the two elements largely overlapped. Therefore, it could be determined that the precipitate in the micrograph 210 was the Fe₃Si precipitate phase.

COMPARATIVE EXAMPLE 1

The initial copper billet composition of Comparative Example 1 was shown in Table 1 above, wherein the initial copper billet of Comparative Example 1 was free of (excluded) silicon element. The process conditions for the copper alloy of Comparative Example 1 were different from those of Experimental Example 1 to Experimental Example 3.

Specifically, after the initial copper billet of Comparative Example 1 was provide, the above-mentioned initial copper billet was heated to obtain the homogeneous copper billet, wherein the heating temperature was 900° C. and the heating temperature holding time was 5 hours. Then, the above-mentioned homogeneous copper billet was quenched to cool it to room temperature, so as to obtain the copper alloy of Comparative Example 1. In other words, the process conditions for Comparative Example 1 excluded the rolling step and the aging step in Experimental Example 1 to Experimental Example 3.

Referring to Table 3 below, it showed the results of the precipitate radius and the mean grain size of Experimental Example 2 and Comparative Example 1.

	TABLE 3
		Precipitate radius	Mean grain size
	Copper alloy	(nm)	(nm)

	Experimental	29.2	659
	Example 2
	(Cu—Fe—Si)
	Comparative	31.7	953
	Example 1
	(Cu—Fe)

In Table 3, the “precipitate radius” and the “mean grain size” were measured by using transmission electron microscope (TEM).

Referring to Table 3, in Experimental Example 2, the “precipitate radius” referred to the radius of the Fe₃Si precipitate phase and the Fe precipitate phase. In Comparative Example 1, the “precipitate radius” referred to the radius of the Fe precipitate phase. In Experimental Example 2, the “mean grain size” referred to the average radius of the grains excluding the Fe₃Si precipitate phase and the Fe precipitate phase. In Comparative Example 1, the “mean grain size” referred to the average radius of the grains excluding the Fe precipitate phase.

It could be known from Table 3 that both the precipitate radius and the mean grain size of Experimental Example 2 were less than those of Comparative Example 1. Because the process steps in Experimental Example 2 had the rolling step (including the hot rolling step and the cold rolling step) and the aging step, the Fe₃Si precipitate phase with a finer radius than the Fe precipitate phase was produced, which could increase the difficulty of dislocation movement and the grain boundary strength, thereby achieving the effects of precipitation strengthening and grain boundary strengthening. Therefore, the tensile strength of the copper alloy of Experimental Example 2 was better than that of Comparative Example 1.

It could be known from Table 2 that the tensile strength, the heat transfer coefficient, and the electrical conductivity of the copper alloy of Comparative Example 1 were all inferior to those of Experimental Example 1 to Experimental Example 3. The copper alloys of Experimental Example 1 to Experimental Example 3 all had the tensile strength greater than 520 MPa, the heat transfer coefficient greater than 290 W/m·K, and the electrical conductivity greater than 57% IACS.

Referring to Table 4 below, which were a comparison table showing properties of the existing C7025 copper alloy and the copper alloys of Experimental Examples 1 to 3.

TABLE 4
	Existing C7025	Copper alloys of Experimental
Comparison	copper alloy	Examples 1 to 3

Tensile strength (MPa)	627	≥522.5
Heat transfer	168.9	≥290.2
coefficient (W/m · K)
Electrical	37.5	≥57.6
conductivity(% IACS)

It could be known from Table 4 that, compared to the existing C7025 copper alloy (containing nickel and manganese elements) currently used for charging terminals, the copper alloys of Experimental Example 1 to Experimental Example 3 all had better heat transfer coefficient and electrical conductivity. Therefore, the copper alloys of Experimental Example 1 to Experimental Example 3 could not only reduce the risk of damage caused by the temperature rise effect, but also could adapt to use in future ultra-high power charging environments. It could effectively reduce heat accumulation and prevent resistance increase caused by the temperature rise effect, thereby enhancing operational safety. Under future scenarios with higher current loads, it further improves overall charging safety and efficiency.

In summary, the present disclosure forms Fe₃Si precipitate phase by adding silicon and iron elements to the initial copper billet, thereby reducing the residual iron element in the copper matrix and increasing the purity of the copper matrix. As a result, the heat transfer coefficient and the electrical conductivity of the obtained copper alloy are enhanced. Also, the precipitation and refinement processing is performed to precipitate the Fe₃Si precipitate phase and strengthen the alloy grain boundaries, thereby enhancing the tensile strength of the copper alloy. The copper alloy of the present disclosure could be applied to electric vehicle connectors (for example, charging terminals of charging plugs), heat sinks of high-power products, or semiconductor lead frames, but is not limited thereto. The copper alloy of the present disclosure has the good heat transfer coefficient, effectively reduces heat energy accumulation, improves usage safety, and lays the foundation for future ultra-high-power charging technologies.

It could be understood that while the present disclosure illustrates the copper alloy and the manufacturing method thereof by specific composition, specific manufacturing method, and specific evaluation approaches as examples, anyone skilled in the art would recognize that the present disclosure is not limited to these examples. Other compositions, alternative manufacturing methods, or different evaluation approaches may also be employed without departing from the spirit and scope of the present disclosure.

The present disclosure has been disclosed as hereinabove, however it is not used to limit the present disclosure. Those skilled in the art may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be subject to the scope of the claims attached in the application.