阅读说明：本技术 一种高功率器件用高强高导铜铬合金及其制备方法 (High-strength high-conductivity copper-chromium alloy for high-power device and preparation method thereof ) 是由 晏弘 王铭 于 2020-12-23 设计创作，主要内容包括：本发明公开了一种高功率器件用高强高导铜铬合金,所述合金所含元素及各元素的重量百分数为：Cr 0.2-1％,Mg 0.01-0.1％,Al 0.01-0.1％,Ag 0.01-0.1％,余量为铜和不可避免的杂质。所述高强高导铜合金的制备方法包括如下步骤：(1)称取原材料；(2)真空熔炼形成铜铬合金熔体；(3)浇铸成扁锭；(4)冷轧成板材；(5)时效处理。本发明铜铬合金具有强度高、导电性好、导热性好的特点,该铜铬合金主要用于集成电路,特别是超大规模集成电路框架、高功率电子器件以及多种电子产品的接插件。(The invention discloses a high-strength high-conductivity copper-chromium alloy for a high-power device, which comprises the following elements in percentage by weight: 0.2 to 1 percent of Cr, 0.01 to 0.1 percent of Mg, 0.01 to 0.1 percent of Al, 0.01 to 0.1 percent of Ag, and the balance of copper and inevitable impurities. The preparation method of the high-strength and high-conductivity copper alloy comprises the following steps: (1) weighing raw materials; (2) vacuum smelting to form a copper-chromium alloy melt; (3) casting into a flat ingot; (4) cold rolling into a plate; (5) and (5) aging treatment. The copper-chromium alloy has the characteristics of high strength, good electrical conductivity and good thermal conductivity, and is mainly used for integrated circuits, in particular very large scale integrated circuit frames, high-power electronic devices and connectors of various electronic products.)

1. The high-strength high-conductivity copper-chromium alloy for the high-power device is characterized by comprising the following elements in percentage by weight: 0.2 to 1 percent of Cr, 0.01 to 0.1 percent of Mg, 0.01 to 0.1 percent of Al, 0.01 to 0.1 percent of Ag, and the balance of copper and inevitable impurities.

2. The high strength high conductivity copper chromium alloy of claim 1 wherein the high purity chromium metal block provides the element Cr; the high-purity magnesium metal block provides Mg element; electrolyzing aluminum to provide Al element; the high-purity silver metal block provides Ag element; TU2 oxygen-free copper provided the remaining copper element.

3. The preparation method of the high-strength high-conductivity copper alloy according to claim 1, wherein the preparation method comprises the following steps:

(1) raw materials: weighing raw materials, wherein the raw materials comprise the following chemical components in percentage by weight: 0.2 to 1 percent of Cr, 0.01 to 0.1 percent of Mg, 0.01 to 0.1 percent of Al, 0.01 to 0.1 percent of Ag, and the balance of copper and inevitable impurities;

(2) vacuum smelting: putting the raw materials weighed in the step (1) into a vacuum induction furnace, wherein the vacuum degree is 6.0-3.0 multiplied by 10^-2Pa, the temperature is 1200-1500 ℃, the temperature is kept for 20-30 minutes, so that the raw materials are completely melted, and the copper-chromium alloy melt is formed by vacuum melting;

(3) casting: casting the copper-chromium alloy melt obtained in the step (2) into a flat ingot, and rapidly cooling the flat ingot to room temperature by water to achieve the purpose of solution treatment;

(4) cold rolling: cold-rolling the slab ingot obtained in the step (3) into a plate with the thickness of 0.2-0.4 mm;

(5) aging treatment: and (4) carrying out aging treatment on the plate obtained in the step (4) at the temperature of 350-450 ℃ for 5-15 hours to obtain the copper-chromium alloy.

Technical Field

The invention relates to the technical field of metal materials, in particular to a high-strength high-conductivity copper-chromium alloy for a high-power device and a preparation method thereof.

Background

Lead frame materials for integrated circuits and semiconductors at home and abroad are classified into two major types, iron-nickel alloy (Fe42Ni) and copper alloy. The iron-nickel alloy has high strength and softening temperature, but low electric conductivity and thermal conductivity, and is mainly used for ceramic and glass packaging. Copper alloy lead frames have been consumed in 90% of the total amount since the twenty-first century because of its excellent electrical conductivity and low cost.

Copper alloys used for lead frames, terminals of electronic devices, connectors, and the like are required to have high strength and high conductivity, and electronic components are required to have high-density packaging property and high reliability because the number of leads on the terminals and connectors is increased and the pitch is reduced rapidly. Therefore, a material used for electronic devices is also required to have excellent processability.

Of these alloys, copper age-hardening alloys are typical representatives of the processes: ingot casting, hot rolling, solution treatment, cold rolling and aging treatment. The processing technology is complex, and the performance of the product is directly influenced.

In order to improve the performance of the product, a number of patents propose methods of adding different trace elements: in order to refine the crystal grains of the copper alloy and further achieve the effect of simultaneously improving the strength and the toughness of the copper alloy, Y is added in an amount which is less than 0.05 percent. In addition, the addition of Y also promotes the oxidation resistance of the copper alloy. In order to improve the strength and the conductivity of the copper alloy, the method adds 0.05 percent of Zr in the smelting process of the copper alloy, and has obvious improvement effect. In addition, the patent also discloses that Co and Sn microelements are added simultaneously to comprehensively improve the strength and the conductivity of the copper alloy. Although the addition of these trace elements improves the properties of the alloy to some extent, the addition of these trace elements is not sufficient to make the properties of the alloy dramatically improved without changing the processing technique of the alloy, and cannot achieve sufficient levels in terms of strength, conductivity, and the like.

Disclosure of Invention

In order to solve the problems in the prior art, the applicant of the present invention provides a high-strength high-conductivity copper-chromium alloy for high power devices and a preparation method thereof. The copper-chromium alloy has the characteristics of high strength, good electrical conductivity and good thermal conductivity, and is mainly used for integrated circuits, in particular very large scale integrated circuit frames, high-power electronic devices and connectors of various electronic products.

The technical scheme of the invention is as follows:

a high-strength high-conductivity copper-chromium alloy for high-power devices comprises the following elements in percentage by weight: 0.2 to 1 percent of Cr, 0.01 to 0.1 percent of Mg, 0.01 to 0.1 percent of Al, 0.01 to 0.1 percent of Ag, and the balance of copper and inevitable impurities.

Providing Cr element by the high-purity chromium metal block; the high-purity magnesium metal block provides Mg element; electrolyzing aluminum to provide Al element; the high-purity silver metal block provides Ag element; TU2 oxygen-free copper provided the remaining copper element.

A preparation method of the high-strength high-conductivity copper alloy comprises the following steps:

(1) raw materials: weighing raw materials, wherein the raw materials comprise the following chemical components in percentage by weight: 0.2 to 1 percent of Cr, 0.01 to 0.1 percent of Mg, 0.01 to 0.1 percent of Al, 0.01 to 0.1 percent of Ag, and the balance of copper and inevitable impurities;

(2) vacuum smelting: putting the raw materials weighed in the step (1) into a vacuum induction furnace, wherein the vacuum degree is 6.0-3.0 multiplied by 10^-2Pa, the temperature is 1200-1500 ℃, the temperature is kept for 20-30 minutes, so that the raw materials are completely melted, and the copper-chromium alloy melt is formed by vacuum melting;

(3) casting: casting the copper-chromium alloy melt obtained in the step (2) into a flat ingot, and rapidly cooling the flat ingot to room temperature by water to achieve the purpose of solution treatment;

(4) cold rolling: cold-rolling the slab ingot obtained in the step (3) into a plate with the thickness of 0.2-0.4 mm;

(5) aging treatment: and (4) carrying out aging treatment on the plate obtained in the step (4) at the temperature of 350-450 ℃ for 5-15 hours to obtain the copper-chromium alloy.

The beneficial technical effects of the invention are as follows:

in the invention, trace Cr element is added into a Cu matrix. Cr atoms tend to enter the crystal lattice of Cu to cause certain crystal lattice distortion, so that the solid solution strengthening effect is generated, the strength of the Cu alloy is obviously improved, and meanwhile, the toughness of the alloy is not greatly lost.

The invention adds Mg element and Ag element into Cu alloy. Mg can remove oxygen in the alloy, reduce defects, promote the condition of reducing the smelting vacuum degree, and improve the conductivity. Mg also plays a role in preventing softening and improving strength. The main function of Ag is to improve the conductivity of Cu alloy.

The invention adds Al element into Cu alloy. Several alloying elements act together to make the alloy have high strength and good electric and thermal conductivity.

The alloy composition of the invention is reasonable, the cost is lower, the prepared copper-chromium alloy has the advantages of high strength, good electrical conductivity, good thermal conductivity and the like, and the copper-chromium alloy can be used for integrated circuits and high-power devices, in particular large-scale and ultra-large-scale integrated circuit frames and connectors of various high-power electronic devices and electronic products. The preparation raw material of the copper-chromium alloy reduces the content of noble metals of silver and chromium, reduces the cost, improves the heat conduction, the electric conduction and the strength, eliminates the hot rolling procedure in the preparation method, simplifies the processing procedure and further reduces the cost.

Detailed Description

The present invention will be described in detail with reference to examples.

Example 1

The copper-chromium alloy comprises the following chemical components in percentage by weight: 0.2% of Cr (chromium), 0.03% of Mg (magnesium), 0.03% of Al (aluminum), 0.01% of Ag (silver), and the balance of copper and inevitable impurities.

The preparation method of the copper-chromium alloy comprises the following steps:

(1) raw materials: according to the weight percentage of the chemical components, weighing high-purity chromium metal blocks, high-purity magnesium metal blocks, electrolytic aluminum, high-purity silver metal blocks and TU2 oxygen-free copper in corresponding weight by calculation;

(2) smelting: adding the weighed high-purity chromium metal block, high-purity magnesium metal block, electrolytic aluminum, high-purity silver metal block and TU2 oxygen-free copper into a vacuum induction furnace, and adjusting the vacuum degree of the induction furnace to 6.0 multiplied by 10^-2Pa, then heating to 1250 ℃, and preserving heat for 25 minutes to completely melt the raw materials to form an alloy melt;

(3) pouring: casting the alloy melt obtained in the step (2) into a casting film, and rapidly cooling the casting film to room temperature by using water to achieve the purpose of solution treatment, so as to obtain a cast ingot with the thickness of 40mm and the width of 105 mm;

(4) cold rolling: cold-rolling the cast ingot obtained in the step (3) into a plate with the thickness of 0.3 mm;

(5) aging treatment: and (3) carrying out aging treatment on the cold-rolled plate at 400 ℃ for 12 hours to obtain the final copper-chromium alloy. The results of the performance tests are shown in table 1.

Example 2

The copper-chromium alloy comprises the following chemical components in percentage by weight: 0.4% of Cr (chromium), 0.06% of Mg (magnesium), 0.06% of Al (aluminum), 0.01% of Ag (silver), and the balance of copper and inevitable impurities.

The preparation method of the copper-chromium alloy comprises the following steps:

(1) raw materials: according to the weight percentage of the chemical components, weighing high-purity chromium metal blocks, high-purity magnesium metal blocks, electrolytic aluminum, high-purity silver metal blocks and TU2 oxygen-free copper in corresponding weight by calculation;

(2) smelting: adding the weighed high-purity chromium metal block, high-purity magnesium metal block, electrolytic aluminum, high-purity silver metal block and TU2 oxygen-free copper into an induction furnace, and adjusting the vacuum degree of the induction furnace to 4.0 multiplied by 10^-2Pa, then heating to 1250 ℃ and preserving heat for 30 minutes to completely melt the raw materials to form an alloy melt;

(3) pouring: casting the alloy melt obtained in the step (2) into a casting film, and rapidly cooling the casting film to room temperature by using water to achieve the purpose of solution treatment, so as to obtain a cast ingot with the thickness of 40mm and the width of 105 mm;

(4) cold rolling: cold-rolling the cast ingot obtained in the step (3) into a plate with the thickness of 0.4 mm;

(5) aging treatment: and (3) aging the cold-rolled plate at 420 ℃ for 10 hours to obtain the final copper-chromium alloy. The results of the performance tests are shown in table 1.

Example 3

The copper-chromium alloy comprises the following chemical components in percentage by weight: 0.5% of Cr (chromium), 0.06% of Mg (magnesium), 0.06% of Al (aluminum), 0.03% of Ag (silver), and the balance of copper and inevitable impurities.

The preparation method of the copper-chromium alloy comprises the following steps:

(1) according to the weight percentage of the chemical components, weighing high-purity chromium metal blocks, high-purity magnesium metal blocks, electrolytic aluminum, high-purity silver metal blocks and TU2 oxygen-free copper in corresponding weight by calculation;

(2) smelting: adding the weighed high-purity chromium metal block, high-purity magnesium metal block, electrolytic aluminum, high-purity silver metal block and TU2 oxygen-free copper into an induction furnace, and adjusting the vacuum degree of the induction furnace to 3.0 multiplied by 10^-2Pa, then heating to 1250 ℃, and preserving heat for 25 minutes to completely melt the raw materials to form an alloy melt;

(3) pouring: casting the alloy melt obtained in the step (2) into a casting film, and rapidly cooling (water cooling) to room temperature to achieve the purpose of solution treatment, so as to obtain a cast ingot with the thickness of 40mm and the width of 105 mm;

(4) cold rolling: cold-rolling the cast ingot obtained in the step (3) into a plate with the thickness of 0.2 mm;

(5) aging treatment: and (3) carrying out aging treatment on the cold-rolled plate at 450 ℃ for 10 hours to obtain the final copper-chromium alloy. The results of the performance tests are shown in table 1.

CN1769507, a high-strength and high-conductivity copper alloy, was used as a comparative example, and the property pairs are shown in Table 1.

TABLE 1

As can be seen from table 1, the present invention applies: 1. the Ag content is reduced, Mg and Al are used for replacing, the raw material cost is reduced, the oxygen defect is reduced, and the vacuum degree condition of low smelting can be used; 2. the elongation is improved, and the alloy with better plastic toughness is obtained; 3. the strength is maintained substantially consistent, but the conductivity is improved; 4. has better heat conductivity coefficient. 5. The performance is improved by using high-purity metal raw materials. Therefore, the alloy of the present invention is particularly suitable for high power devices.