A heat dissipation copper alloy foil for motor equipment and its manufacturing process

Abstract

The invention discloses a heat dissipation copper alloy foil for motor equipment and a manufacturing process thereof. The heat dissipation copper alloy foil comprises, by mass percentage, the following components: Al: 0.1% to 1%; Ni: 1% to 5%; Si: 0.1% to 0.5%; Sn: 0.1% to 1%; Zn: 1% to 3%; Y: 0.05% to 0.5%; Fe: 0.01% to 1%; Mn: 0.01% to 1%; S: 0.01% to 1%; the balance is Cu. The invention creates a copper alloy foil with excellent thermal conductivity by precisely controlling the proportions of main alloy elements such as aluminum (Al), nickel (Ni), silicon (Si), tin (Sn), zinc (Zn), yttrium (Y), iron (Fe), manganese (Mn), sulfur (S), and optionally adding magnesium (Mg) or lead (Pb). These alloy elements not only enhance the strength and corrosion resistance of the material, but also significantly improve the thermal conductivity efficiency by optimizing the microstructure and electron transmission path.

Description

Technical Field

[0001] The invention relates to the technical field of heat dissipation copper alloy foil manufacturing, and in particular to a heat dissipation copper alloy foil for motor equipment and a manufacturing process thereof. Background Art

[0002] Motor equipment will generate a lot of heat during operation. In order to maintain its stable operation, materials with good heat dissipation performance are needed to assist in heat dissipation. Heat dissipation copper alloy foil has excellent thermal conductivity and can quickly conduct the heat generated inside the motor equipment. This is crucial to preventing the motor from overheating and ensuring stable operation of the equipment. Therefore, it is widely used in the heat dissipation system of motor equipment. Heat dissipation copper alloy foil is mainly composed of copper and its alloy elements. By adjusting the type and content of alloy elements, heat dissipation copper alloy foil with excellent thermal conductivity and mechanical properties can be obtained.

[0003] The patent number CN111774572B discloses a high heat dissipation copper foil for electronic equipment and a preparation method thereof. The patent includes the following raw materials in weight proportion: 120-125 parts of methyl vinyl MQ high viscosity silicone resin, 75-87 parts of graphene powder, 1-3 parts of cadmium oxide, 2-4 parts of antimony oxide, 1-3 parts of molybdenum trioxide, 324-335 parts of copper powder, 2-4 parts of nano beryllium, 38-77 parts of nano aluminum nitride, 55-60 parts of aluminum powder, 3-5 parts of magnesium silicide, 1-3 parts of scandium oxide, 20-22 parts of nano titanium and 7-9 parts of nano zirconium. The high heat dissipation copper foil for electronic equipment has excellent Thermal conductivity can be used in various electronic devices, but this patent uses as many as 13 raw materials, and the weight ratio of each raw material is wide, which increases the complexity of raw material selection and ratio, including methyl vinyl MQ high viscosity silicone resin, graphene powder, various metal oxides and metal powders, etc. The procurement and ratio of these raw materials are relatively complicated, which may lead to high production costs, and a variety of chemical raw materials are used. The use of multiple chemical raw materials may involve complex processing processes, including mixing, sintering, calendering, etc. If handled improperly, these processes may produce harmful waste or emissions, causing certain impacts on the environment.

[0004] Therefore, it is necessary to invent a heat dissipation copper alloy foil for motor equipment and a manufacturing process thereof to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a heat dissipation copper alloy foil for motor equipment and a manufacturing process thereof, so as to solve the relatively complex procurement and proportioning of raw materials in the technology, which may lead to high production costs, and the use of a variety of chemical raw materials. The use of a variety of chemical raw materials may involve complex processing processes, including mixing, sintering, calendering, etc., which may produce harmful waste or emissions and have a certain impact on the environment.

[0006] In order to achieve the above object, the present invention provides the following technical solution: A heat dissipation copper alloy foil for motor equipment, comprising, by mass percentage:

[0007] Al: 0.1%~1%;

[0008] Ni: 1% to 5%;

[0009] Si: 0.1%~0.5%;

[0010] Sn: 0.1%~1%;

[0011] Zn: 1% to 3%;

[0012] Y: 0.05%~0.5%;

[0013] Fe: 0.01%~1%;

[0014] Mn: 0.01%~1%;

[0015] S: 0.01%~1%;

[0016] The remainder is Cu;

[0017] It also contains at least one of the following elements: Mg, whose content is 0.01% to 0.5%; or Pb, whose content is 0.01% to 0.5%.

[0018] Preferably, the manufacturing process includes the following:

[0019] Raw material preparation → hot pressing and tempering → chipping and cold rolling → rolling and degreasing and drying → surface treatment → aging treatment and performance testing → cutting and packaging.

[0020] Preferably, the raw material preparation includes selecting high-purity copper-based alloy raw materials, adding appropriate amounts of aluminum, nickel, silicon, tin, zinc and yttrium alloy elements for matching, and during the raw material preparation stage, adding appropriate amounts of magnesium or lead elements to help improve the comprehensive properties of the copper alloy foil, such as strength, toughness, corrosion resistance and thermal conductivity.

[0021] Preferably, the hot pressing adopts a roller hot press, the temperature range of the hot pressing is between 800°C and 1200°C, the internal temperature of the roller hot press is accurately controlled to ±5°C, the tempering and toughening adopts oil tempering, the tempering temperature range is between 350°C and 650°C, and during the hot pressing process, nitrogen or inert gas protection is used to optimize the microstructure of the copper alloy foil and improve the mechanical properties and processing properties of the material. At the same time, the use of nitrogen or inert gas protection can prevent the material from oxidizing at high temperature and ensure product quality.

[0022] Preferably, in the scaling and cold rolling process, multiple cold rolling and intermediate annealing treatment are used. The process starts with the drawn material after forging, and its initial billet thickness is 130 mm. After multiple cold rolling, it reaches an intermediate thickness of 11 mm. Thereafter, the billet will continue to undergo multiple cold rolling and intermediate annealing treatments to roll the billet thickness from 11 mm to 2.5 mm, which can gradually refine the grains of the material, improve the strength and toughness of the material, and at the same time ensure the thickness uniformity and surface quality of the material.

[0023] Preferably, in the cold rolling process, a 2.5 mm thick billet can be transferred to a four-roll mill for further rolling to a thickness of 0.9 mm. Subsequently, the 0.9 mm thick billet is pickled, trimmed and solution treated in an air cushion furnace and then finely rolled to 0.27 mm in the rolling mill. The subsequent pre-finished product rolling and finished product rolling are all carried out in the four-roll mill. The tolerance of the finished product rolling is basically maintained at ±2.5 μm. The finished product rolling is all rolled according to a negative tolerance of +0 / -0.01 mm. Reasonable rolling speed and tension control can further improve the surface quality and performance of the material.

[0024] Preferably, the rolling speed during cold rolling is ≤25m / min, and the front and rear tensions are maintained at 43kN. The lower rolling speed helps to ensure that the material is subjected to a more uniform and stable pressure during the rolling process, thereby avoiding problems such as internal stress concentration, crack generation or surface quality degradation of the material due to excessive speed.

[0025] Preferably, in the rolling and degreasing and drying process, continuous rolling and high-efficiency degreasing and drying equipment are used to ensure the surface cleanliness and dryness of the copper alloy foil, providing a good foundation for subsequent surface treatment processes.

[0026] Preferably, in the surface treatment process, chemical etching or electrochemical polishing technology is used, and after the surface treatment, a heat-conducting layer coating step is also included, the heat-conducting layer uses graphene, graphene oxide or a mixture thereof as a coating, and is applied to the surface of the copper alloy foil by spraying, brushing, rolling or dipping, which can improve the surface finish and corrosion resistance of the copper alloy foil. At the same time, coating the heat-conducting layer after the surface treatment, using graphene, graphene oxide or a mixture thereof as a coating, can further improve the thermal conductivity of the material to meet the needs of specific application scenarios.

[0027] Preferably, the aging treatment and performance testing include aging treatment, stretching and straightening and performance testing. The aging treatment adopts a bell furnace, the temperature in the bell furnace is raised to 400°C for 4.5 hours and kept warm for 10 hours. The stretching and straightening uses a stretching and straightening machine to further improve the edge wave phenomenon of the strip and achieve perfect flatness, which can further optimize the microstructure and mechanical properties of the copper alloy foil.

[0028] Preferably, the finished product striping and packaging includes cutting into finished copper alloy foil sheets and packaging and storage, which can ensure the safety and stability of the product during transportation and use.

[0029] In the above technical solution, the technical effects and advantages provided by the present invention are:

[0030] 1. The present invention creates a copper alloy foil with excellent thermal conductivity by precisely controlling the proportions of major alloying elements such as aluminum (Al), nickel (Ni), silicon (Si), tin (Sn), zinc (Zn), yttrium (Y), iron (Fe), manganese (Mn), sulfur (S), and optionally adding magnesium (Mg) or lead (Pb). These alloying elements not only enhance the strength and corrosion resistance of the material, but also significantly improve the thermal conductivity efficiency by optimizing the microstructure and electron transmission path;

[0031] 2. The present invention uses graphene, graphene oxide or a mixture thereof as a coating, which is applied to the surface of the copper alloy foil by spraying, brushing, rolling or dipping to form a high-efficiency heat-conducting layer. Graphene and its derivatives, with their excellent thermal conductivity and mechanical strength, further enhance the heat dissipation capacity of the foil, enabling it to more effectively conduct the heat generated by the motor equipment and ensure stable operation of the equipment;

[0032] 3. The present invention ensures that the copper alloy foil has extremely high dimensional accuracy and surface flatness through multiple cold rolling with intermediate annealing treatment and finish rolling with a four-roll rolling mill, and the rolling tolerance of the finished product is basically maintained at ±2.5μm, and is rolled according to a negative tolerance of +0 / -0.01mm, which not only meets the high-precision requirements of motor equipment for heat dissipation materials, but also improves the reliability and service life of the product. In addition, through aging treatment, stretching and straightening, and performance testing, the microstructure and mechanical properties of the copper alloy foil are further improved, internal stress is eliminated, and the toughness and fatigue resistance of the material are improved. At the same time, strict performance testing ensures that each batch of products meets the specified quality standards, thereby ensuring the heat dissipation effect and overall performance of the motor equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the manufacturing process of the copper alloy foil of the present invention;

[0034] Figure 2 It is a schematic diagram of a forged rectangular flat ingot blank of the present invention;

[0035] Figure 3 It is a schematic diagram of the structure of the roller system of the four-roller middle rolling mill of the present invention;

[0036] Figure 4 It is a schematic diagram of a coil after annealing in a bell-type annealing furnace of the present invention;

[0037] Figure 5 It is a schematic diagram of the lower half of the set roller box of the present invention. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0039] The present invention provides Figure 1-5 A heat dissipation copper alloy foil for motor equipment shown in the figure comprises, by mass percentage:

[0040] Al: 0.1%~1%;

[0041] Ni: 1% to 5%;

[0042] Si: 0.1%~0.5%;

[0043] Sn: 0.1%~1%;

[0044] Zn: 1% to 3%;

[0045] Y: 0.05%~0.5%;

[0046] Fe: 0.01%~1%;

[0047] Mn: 0.01%~1%;

[0048] S: 0.01%~1%;

[0049] The remainder is Cu;

[0050] It also contains at least one of the following elements: Mg, whose content is 0.01% to 0.5%; or Pb, whose content is 0.01% to 0.5%.

[0051] The manufacturing process includes the following:

[0052] Raw material preparation → hot pressing and tempering → chipping and cold rolling → rolling and degreasing and drying → surface treatment → aging treatment and performance testing → cutting and packaging.

[0053] Raw material preparation includes selecting high-purity copper-based alloy raw materials, adding appropriate amounts of aluminum, nickel, silicon, tin, zinc and yttrium alloy elements for matching. During the raw material preparation stage, appropriate amounts of magnesium or lead elements are also added.

[0054] Various metal raw materials are accurately weighed according to the above ratio. Aluminum has good thermal conductivity and can significantly improve the heat dissipation efficiency of copper alloy foil. The addition of nickel can improve the thermal stability and oxidation resistance of the alloy, which helps to maintain the stability of the heat dissipation performance. The addition of silicon can refine the grains of the alloy, improve the strength and hardness of the alloy, and also help to improve the heat dissipation performance. The addition of zinc can improve the strength and toughness of the alloy, so that the foil is not easy to deform or break when subjected to external force. The addition of manganese can improve the hardness and wear resistance of the alloy and extend the service life of the foil. The addition of magnesium can further improve the strength and toughness of the alloy, and also help to improve the corrosion resistance of the alloy. The addition of tin can improve the corrosion resistance of the alloy and prevent the foil from oxidation or corrosion in a humid or corrosive environment. Yttrium is a rare earth element. Its addition can significantly improve the corrosion resistance of the alloy, and also help to improve the strength and toughness of the alloy. The addition of iron and sulfur can adjust the properties of the alloy to a certain extent, such as improving the hardness, wear resistance or corrosion resistance of the alloy. At the same time, their content is controlled at a low level to avoid adverse effects on the main properties of the alloy. The addition of magnesium can further improve the strength and toughness of the alloy, and also helps to improve the corrosion resistance of the alloy, while an appropriate amount of lead can further improve the plasticity and toughness of the alloy, and also help to reduce the density and cost of the alloy.

[0055] The hot pressing adopts a roller hot press, the temperature range of hot pressing is between 800℃ and 1200℃, the internal temperature of the roller hot press is accurately controlled to ±5℃, the tempering and toughening adopts oil tempering, the tempering temperature range is between 350℃ and 650℃, and nitrogen or inert gas protection is adopted during the hot pressing process.

[0056] High temperature hot pressing treatment by roller hot press can fully plasticize and flow the material, fill the gaps in the mold, form a dense structure, and thus improve the density and strength of the material. Oil tempering treatment can effectively eliminate the residual stress in the material, improve the toughness and plasticity of the material, and make it have better impact resistance and fatigue resistance. During the hot pressing process, nitrogen or inert gas is used for protection. Nitrogen or inert gas has stable chemical properties and is not easy to react chemically with the material, which can effectively prevent the material from oxidation, corrosion and other adverse reactions at high temperatures.

[0057] In the scaling and cold rolling process, multiple cold rolling and intermediate annealing are used. The process starts with the drawn material after forging. The initial billet thickness is 130mm. After multiple cold rolling, the intermediate thickness reaches 11mm. After that, the billet will continue to undergo multiple cold rolling and intermediate annealing to roll the billet thickness from 11mm to 2.5mm. In the cold rolling process, the 2.5mm thick billet can be transferred to the four-roll mill for further rolling to 0.9mm thickness. Subsequently, the 0.9mm thick billet is pickled, trimmed and solution treated in an air cushion furnace and then continued to be finish rolled to 0.27mm in the rolling mill. The subsequent pre-finished product rolling and finished product rolling are all carried out in the four-roll mill. The tolerance of the finished product rolling is basically maintained at ±2.5μm, and the finished product rolling is rolled according to the negative tolerance of +0 / -0.01mm. The rolling speed during cold rolling is ≦25m / min, and the front and rear tensions are maintained at 43kN.

[0058] The initial billet is sent to the cold rolling mill for multiple cold rolling, and its thickness is gradually rolled from 130mm to 11mm. In this process, the number of cold rolling and the amount of reduction each time need to be precisely controlled according to the mechanical properties of the material and the capacity of the cold rolling mill. In the cold rolling process, in order to eliminate the work hardening and internal stress of the material and improve the processing performance of the material, intermediate annealing is required. This treatment is usually carried out after cold rolling to a certain thickness to ensure that the material can maintain good plasticity and toughness in the subsequent cold rolling process. After the initial cold rolling and annealing treatment, the billet will continue to undergo multiple cold rolling until its thickness reaches about 2.5mm. In this process, the number of cold rolling and the amount of reduction also need to be strictly controlled, and additional annealing may be required. The intermediate annealing treatment is performed to ensure the mechanical properties and processing properties of the material. The 2.5mm thick billet is transferred to the four-roll mill for further rolling until its thickness reaches 0.9mm. Due to its unique roll system design, the four-roll mill can provide more uniform rolling pressure and better plate shape control. After the billet is rolled to 0.9mm, it is necessary to pickle it to remove the oxide scale and oil on the surface, and then trim it to remove the irregular parts of the edge. Finally, the billet is sent to the air cushion furnace for solution treatment to further improve its mechanical properties and corrosion resistance. After the above treatment, the billet continues to be finish rolled on the four-roll mill until its thickness reaches the final 0.27mm. The specific process parameters are shown in Tables 1 and 2 below.

[0059] Table 1 Cold rolling 2.5mm-0.9mm process parameters

[0060] path 1 2 3 4 5 6 7 Thickness before rolling 2.5 2.15 1.85 1.595 1.375 1.185 1.03 Thickness after rolling 2.15 1.85 1.595 1.375 1.185 1.03 0.898 Processing rate 14.00％ 13.95％ 13.78％ 13.79％ 13.82％ 13.08％ 12.82％ Rolling force / KN 1897 2150 2163 2025 2100 1908 1839 Front tension / KN 31.2 29.3 29.2 27.3 25.2 23.4 21.5 Post tension / KN 29.5 31.6 31.4 29.5 27.4 25.5 23.5 Host current / A 630 560 455 463 352 349 285 Rolling speed m / min 14 72 88 84 85 97 101 Bending roll force / KN ﹢20 ﹢18 ﹢17 ﹢16 ﹢15 ﹢14 ﹢13

[0061] Table 2 Cold rolling 0.9mm-0.27mm process parameters

[0062]

[0063]

[0064] In the calendering and degreasing and drying process, continuous calendering and high-efficiency degreasing and drying equipment are used. In the surface treatment process, chemical etching or electrochemical polishing technology is used. After the surface treatment, a thermal conductive layer coating step is also included. The thermal conductive layer uses graphene, graphene oxide or a mixture thereof as a coating, which is applied to the surface of the copper alloy foil by spraying, brushing, rolling or dipping. The aging treatment and performance testing include aging treatment, stretching and straightening, and performance testing. The aging treatment adopts a bell furnace, and the temperature in the bell furnace is raised to 400°C for 4.5 hours and kept warm for 10 hours. A stretching and bending straightening machine is used for stretching and straightening to further improve the edge wave phenomenon of the strip and achieve perfect flatness.

[0065] Setting up continuous calendering and efficient degreasing and drying equipment can ensure the thickness, flatness and cleanliness of the foil, providing a good foundation for subsequent surface treatment and thermal conductive layer coating. Chemical etching or electrochemical polishing technology can improve the smoothness and uniformity of the foil surface, further improving the quality and performance of the product. Graphene, graphene oxide or their mixtures are selected as coatings. These materials have excellent thermal conductivity and chemical stability, which can effectively improve the thermal conductivity of copper alloy foil. Aging treatment can change the internal microstructure of the foil, further improving its mechanical properties and thermal conductivity. The diameter of the roller in the roller box of the stretch-bend straightening machine that is in direct contact with the strip surface is small (d≈16mm). The stretch-bend straightening treatment can further improve the edge wave phenomenon of the foil, so that it can achieve perfect flatness and improve the aesthetics and use effect of the product.

Claims

1. A heat dissipation copper alloy foil for motor equipment, characterized in that: Included by mass percentage: Al：0.1％～1％； Ni: 1% to 5%; Si: 0.1%~0.5%; Sn: 0.1%~1%; Zn: 1% to 3%; Y：0.05％～0.5％； Fe: 0.01%~1%; Mn: 0.01%~1%; S：0.01％～1％； The remainder is Cu; It also contains at least one of the following elements: Mg, whose content is 0.01% to 0.5%; or Pb, whose content is 0.01% to 0.5%.

2. A manufacturing process for preparing the heat dissipation copper alloy foil as claimed in claim 1, characterized in that: The manufacturing process includes the following: Raw material preparation → hot pressing and tempering → chipping and cold rolling → rolling and degreasing and drying → surface treatment → aging treatment and performance testing → cutting and packaging.

3. The manufacturing process according to claim 2, characterized in that: The raw material preparation includes selecting high-purity copper-based alloy raw materials, adding appropriate amounts of aluminum, nickel, silicon, tin, zinc and yttrium alloy elements for matching, and in the raw material preparation stage, adding appropriate amounts of magnesium or lead elements.

4. The manufacturing process according to claim 2, characterized in that: The hot pressing adopts a roller hot press, the temperature range of the hot pressing is between 800°C and 1200°C, the internal temperature of the roller hot press is accurately controlled to ±5°C, the tempering and toughening adopts oil tempering, the tempering temperature range is between 350°C and 650°C, and nitrogen or inert gas protection is adopted during the hot pressing process.

5. The manufacturing process according to claim 2, characterized in that: In the scaling and cold rolling process, multiple cold rolling and intermediate annealing are used. The process starts with the drawn material after forging, and its initial billet thickness is 130 mm. After multiple cold rolling, the intermediate thickness reaches 11 mm. After that, the billet will continue to undergo multiple cold rolling and intermediate annealing to reduce the billet thickness from 11 mm to 2.5 mm.

6. The manufacturing process according to claim 5, characterized in that: In the cold rolling process, the 2.5mm thick billet can be transferred to the four-roll mill for further rolling to 0.9mm thickness. Subsequently, the 0.9mm thick billet is pickled, trimmed and solution treated in an air cushion furnace and then continued to be finish rolled to 0.27mm in the rolling mill. The subsequent pre-finished product rolling and finished product rolling are all carried out in the four-roll mill. The tolerance of the finished product rolling is basically maintained at ±2.5μm, and the finished product rolling is rolled according to the negative tolerance of +0 / -0.01mm.

7. The manufacturing process according to claim 6, characterized in that: The rolling speed during the cold rolling is ≤25m / min, and the front and rear tensions are maintained at 43kN.

8. The manufacturing process according to claim 2, characterized in that: In the calendering and degreasing and drying process, continuous calendering and high-efficiency degreasing and drying equipment are used.

9. The manufacturing process according to claim 2, characterized in that: In the surface treatment process, chemical etching or electrochemical polishing technology is used, and after the surface treatment, a thermal conductive layer coating step is also included. The thermal conductive layer uses graphene, graphene oxide or a mixture thereof as a coating and is applied to the surface of the copper alloy foil by spraying, brushing, rolling or dipping.

10. The manufacturing process according to claim 2, characterized in that: The aging treatment and performance testing include aging treatment, stretching and straightening and performance testing. The aging treatment adopts a bell furnace, the temperature in the bell furnace is raised to 400°C for 4.5 hours and kept warm for 10 hours. The stretching and straightening uses a stretching and straightening machine to further improve the edge wave phenomenon of the strip and achieve perfect flatness.

Images