Preparation method of copper-phosphorus alloy

Abstract

The invention relates to the field of alloy smelting, and discloses a copper-phosphorus alloy preparation method, which comprises the following steps of: performing conversion adjustment on a first induction frequency and a second induction frequency of a vacuum induction furnace to enable a copper-phosphorus melt in the vacuum induction furnace to generate oscillation in a frequency conversion process between the first induction frequency and the second induction frequency, and then casting to obtain the copper-phosphorus alloy, the frequency difference between the first induction frequency and the second induction frequency is at least 1500 Hz, and the respective hold time of the first induction frequency and the second induction frequency is 1-10 s. According to the preparation method, the uniformity of the copper-phosphorus alloy can be improved at low cost.

Description

Technical Field

[0001] The invention relates to the field of alloy smelting, and in particular to a method for preparing a copper-phosphorus alloy. Background Art

[0002] At present, most domestic and foreign companies use vacuum induction melting technology to produce copper-phosphorus alloy ingots. Since the density of phosphorus is lower than that of copper, the uniformity of phosphorus is improved by adding copper-phosphorus intermediate alloys. However, simply adding copper-phosphorus intermediate alloys cannot fully meet the use requirements, and during the casting process, copper-phosphorus alloys are prone to shrinkage cavities. Among the current methods, some use tilting smelting furnaces to improve uniformity, and some use the method of adding risers to reduce shrinkage cavities. However, in actual operation, the tilt angle of the tilted smelting furnace may be difficult to achieve due to the large furnace load and mold position restrictions, affecting the homogenization effect. Risers are generally used to improve the utilization rate of ingots, but the riser manufacturing process is complicated and difficult to clean.

[0003] CN202010955038 discloses a smelting method for preparing a copper-phosphorus alloy using a copper-phosphorus master alloy, comprising: melting a copper raw material under vacuum conditions and performing a first standing, then introducing a protective gas, then adding a copper-phosphorus master alloy, tilting a melting device, and then performing a second standing and casting. This method solves the problem of phosphorus segregation in the preparation process of the copper-phosphorus alloy by specifically selecting the timing and conditions for adding the copper-phosphorus master alloy, and adopting a tilting method in the subsequent process, and utilizing the synergistic coupling effect between the two. It also improves the uniformity of phosphorus in the copper-phosphorus ingot, controls the total phosphorus content, improves the quality of the copper-phosphorus anode, and meets the chip production requirements. However, the tilting melting device may fail to reach the corresponding tilting angle due to excessive furnace loading or limited position, affecting the effect.

[0004] CN201010581922 discloses a method for preparing a phosphor copper anode for an integrated circuit. The method comprises the following steps: using high-purity graphite as a crucible and a mold material, melting a high-purity copper ingot with a purity of 99.99% or more in a high-vacuum medium-frequency induction melting furnace, adding a phosphor copper master alloy containing 6 to 16 wt% phosphorus at 1150 to 1300°C, wherein the weight ratio of the phosphor copper master alloy to the high-purity copper ingot is 1:50 to 600, and heat-keeping the ingot at 1150 to 1300°C for 20 to 30 minutes, and then standing the ingot for 20 minutes, and then pouring the ingot into a graphite mold to obtain a phosphor copper alloy ingot. After the ingot riser is cut off, the obtained phosphor copper alloy ingot is subjected to multi-directional forging and rolling, and subjected to recrystallization treatment at 300 to 600°C for 0.5 to 12 hours, and then subjected to surface treatment to mechanically process the phosphor copper anode for an integrated circuit. The phosphor copper anode prepared by this method has the characteristics of low impurity content, low oxygen content, uniform phosphorus content distribution, fine and uniform grains, etc. However, this method improves uniformity by setting a riser and subsequent heat treatment, which increases the riser and subsequent heat treatment, increases the processing steps, and increases the cost.

[0005] Therefore, the technical problem to be solved by the present invention is: how to improve the uniformity of copper-phosphorus alloy at low cost. Summary of the invention

[0006] The main purpose of the present invention is to provide a method for preparing a copper-phosphorus alloy. By changing the induction frequency of a vacuum induction furnace, the vacuum induction furnace is switched and adjusted between a first induction frequency and a second induction frequency, and the stirring force given by electromagnetic to the copper-phosphorus alloy melt in the vacuum induction furnace is changed, thereby producing a vibration effect on the copper-phosphorus alloy melt, so that the component distribution of the copper-phosphorus alloy is more uniform.

[0007] To achieve the above objectives, the technical solutions adopted in this application are:

[0008] A method for preparing a copper-phosphorus alloy comprises the following steps: by converting and adjusting a first induction frequency and a second induction frequency of a vacuum induction furnace, a copper-phosphorus melt in the vacuum induction furnace is caused to oscillate during a frequency conversion process between the first induction frequency and the second induction frequency, and then the copper-phosphorus alloy is cast; the frequency difference between the first induction frequency and the second induction frequency is at least 1500 Hz, and the first induction frequency and the second induction frequency are maintained for 1 to 10 seconds respectively.

[0009] Since the induction frequency will produce a stirring force on the copper-phosphorus solution, and the stirring force is inversely proportional to the square of the induction frequency, by changing the induction frequency of the vacuum induction furnace, maintaining the induction frequency of the vacuum induction furnace at 300-700 Hz for a period of time, and then maintaining the induction frequency of the vacuum induction furnace at 1800-2500 Hz for a period of time, the stirring force of the vacuum induction furnace on the copper-phosphorus melt will produce an effect of rapidly increasing or rapidly decreasing, causing the copper-phosphorus melt to produce changing eddy currents, thereby producing an oscillation effect on the copper-phosphorus alloy melt, thereby making the copper element and phosphorus element in the copper-phosphorus melt more evenly mixed.

[0010] In the scheme of the present invention, the maintenance time of the first induction frequency can be selected as 1s, 2s, 3s, 4s, 5s, 6s, 7s, 8s, 9s, 10s, and the maintenance time of the second induction frequency can be selected as 1s, 2s, 3s, 4s, 5s, 6s, 7s, 8s, 9s, 10s.

[0011] Preferably, the frequency difference between the first induction frequency and the second induction frequency is 1500-2200 Hz.

[0012] In the solution of the present invention, the frequency difference between the first induction frequency and the second induction frequency is preferably 1500 Hz, 1600 Hz, 1700 Hz, 1800 Hz, 1900 Hz, 2000 Hz, 2100 Hz, or 2200 Hz.

[0013] Preferably, the first induction frequency is 300-700 Hz; the second induction frequency is 1800-2500 Hz.

[0014] In the solution of the present invention, the first induction frequency can be selected as 300Hz, 350Hz, 400Hz, 450Hz, 500Hz, 550Hz, 600Hz, 650Hz, 700Hz; the second induction frequency can be selected as 1800Hz, 1900Hz, 2000Hz, 2100Hz, 2200Hz, 2300Hz, 2400Hz, 2500Hz.

[0015] More preferably, the first induction frequency and the second induction frequency can be interchanged, that is, the first induction frequency is 1800-2500 Hz, and the second induction frequency is 300-700 Hz.

[0016] Preferably, the number of conversions between the first induction frequency and the second induction frequency is 3 to 10 times.

[0017] In the solution of the present invention, the number of conversions between the first induction frequency and the second induction frequency can be selected to be 3 times, 4 times, 5 times, 6 times, 7 times, 8 times, 9 times, or 10 times.

[0018] Preferably, the copper-phosphorus melt is prepared by the following steps:

[0019] Step a: placing copper in a vacuum induction furnace and heating it to obtain copper melt;

[0020] Step b: introducing a protective gas into the vacuum induction furnace until the gas pressure in the vacuum induction furnace is 20-50 kPa, adding a copper-phosphorus master alloy, keeping the temperature and standing to obtain a copper-phosphorus melt; the copper-phosphorus master alloy has a phosphorus content of 5-15wt%, and the balance is copper; the copper-phosphorus melt has a phosphorus content of 0.04-0.065wt%, and the balance is copper.

[0021] In the scheme of the present invention, the protective gas is introduced into the vacuum induction furnace until the gas pressure in the vacuum induction furnace can be selected to be 20kPa, 25kPa, 30kPa, 35kPa, 40kPa, 45kPa, or 50kPa.

[0022] The phosphorus content of the copper-phosphorus master alloy may be selected to be 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, or 15wt%.

[0023] The phosphorus content in the copper-phosphorus melt can be selected to be 0.04wt%, 0.05wt%, or 0.065wt%.

[0024] Preferably, the heating temperature of step a is 1100-1300° C., the heating time is 15-45 min, and the vacuum degree is 0.01-1 Pa.

[0025] In the scheme of the present invention, the heating temperature can be selected as 1100°C, 1150°C, 1200°C, 1250°C, or 1300°C.

[0026] The heating time can be selected as 15min, 20min, 25min, 30min, 35min, 45min.

[0027] The vacuum degree can be selected as 0.01Pa, 0.1Pa, 0.2Pa, 0.3Pa, 0.4Pa, 0.5Pa, 0.6Pa, 0.7Pa, 0.8Pa, 0.9Pa, and 1Pa.

[0028] Preferably, the insulation temperature of step b is 1100-1300° C. and the standing time is 10-50 min.

[0029] In the solution of the present invention, the insulation temperature can be selected as 1100°C, 1150°C, 1200°C, 1250°C, 1300°C;

[0030] The standing time can be selected as 10min, 15min, 20min, 25min, 30min, 35min, 40min, 45min, 50min.

[0031] Preferably, the method comprises the following steps:

[0032] Step 1: adjusting the induction frequency of the vacuum induction furnace to a first induction frequency to treat the copper-phosphorus molten liquid in the vacuum induction furnace, maintaining the first induction frequency for 1 to 10 seconds, and then adjusting the induction frequency of the vacuum induction furnace to a second induction frequency, maintaining the second induction frequency for 1 to 10 seconds; repeating the above operation at least 3 times to obtain a copper-phosphorus alloy molten liquid;

[0033] The phosphorus content in the copper-phosphorus melt is 0.04-0.065wt%, and the balance is copper;

[0034] Steps: Casting to obtain copper-phosphorus alloy.

[0035] Preferably, the step 2 is specifically as follows: casting the copper-phosphorus alloy melt and cooling the bottom of the copper-phosphorus alloy solution, the cooling temperature is 10-50°C, and the cooling time is 1-8 minutes; reducing the copper-phosphorus alloy melt to below 100°C within 11 hours to obtain the copper-phosphorus alloy.

[0036] Preferably, the step 2 is specifically as follows: 70-95wt% of the copper-phosphorus alloy melt is cast once to obtain a primary casting liquid, the bottom of the primary casting liquid is cooled at a cooling temperature of 10-50°C for a cooling time of 1-8min; the remaining copper-phosphorus alloy melt is cast on the primary casting liquid, and the copper-phosphorus alloy melt is cooled to below 100°C within 11h to obtain the copper-phosphorus alloy. This parameter has little effect on the preparation method, and the preparation method can be realized within this parameter.

[0037] In the scheme of the present invention, 70wt%, 75wt%, 80wt%, 85wt%, 90wt% and 95wt% of the copper-phosphorus alloy melt can be cast once to obtain a primary casting liquid.

[0038] The cooling temperature can be selected as 10℃, 20℃, 30℃, 40℃, 50℃.

[0039] The cooling time can be selected as 1min, 2min, 3min, 4min, 5min, 6min, 7min, 8min.

[0040] The copper-phosphorus alloy melt can be reduced to below 100°C within 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, or 11h.

[0041] Compared with the prior art, this solution has the following beneficial effects:

[0042] The copper-phosphorus alloy preparation method of the present invention changes the induction frequency of the vacuum induction furnace, maintains the induction frequency of the vacuum induction furnace at a first induction frequency for a period of time, and then maintains the induction frequency of the vacuum induction furnace at a second induction frequency for a period of time, and changes the stirring force given to the copper-phosphorus alloy melt in the vacuum induction furnace by electromagnetic induction in a manner of continuously switching between the first induction frequency and the second induction frequency, thereby generating an oscillation effect on the copper-phosphorus alloy melt, thereby achieving a stronger stirring effect on the copper-phosphorus alloy melt, and making its component distribution more uniform.

[0043] Moreover, by controlling the number and time of adjusting the vacuum induction furnace, the temperature of the vacuum induction furnace is avoided from changing and the induction frequency of the stirring force is kept within a suitable range, thereby improving the uniformity of the copper-phosphorus alloy and avoiding phosphorus segregation. No additional devices are needed to improve the uniformity of phosphorus and reduce costs.

[0044] Secondly, the copper-phosphorus alloy melt is cast in two times, which reduces the shrinkage cavity of the copper-phosphorus alloy. Moreover, this method does not require the use of a riser, is simple to operate, and has a low cost. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application is clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the present application implemented as generally shown here can be arranged and designed in various different configurations.

[0046] The copper-phosphorus melts used in the following examples and comparative examples were all prepared by the following steps:

[0047] Step a: adjusting the vacuum degree of the vacuum induction furnace to 0.5 Pa, placing copper in the vacuum induction furnace for heating, the heating time is 30 minutes, the heating temperature is 1200° C., and obtaining a copper melt;

[0048] Step b: introducing a protective gas into the vacuum induction furnace until the gas pressure in the vacuum induction furnace is 30 kPa, adding a copper-phosphorus master alloy with a phosphorus content of 10 wt % and a balance of copper, and keeping it at a holding temperature of 1200° C. for 30 min to obtain a copper-phosphorus melt with a phosphorus content of 0.05 wt % and a balance of copper.

[0049] Example 1

[0050] A method for preparing a copper-phosphorus alloy comprises the following steps:

[0051] Step 1: The induction frequency of the vacuum induction furnace is adjusted to 500 Hz to treat the copper-phosphorus molten liquid in the vacuum induction furnace, and the first induction frequency is maintained for 5 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 2000 Hz, and the second induction frequency is maintained for 5 seconds; the above operation is repeated 7 times to obtain a copper-phosphorus alloy molten liquid;

[0052] Step 2: Casting the copper-phosphorus alloy melt, cooling the copper-phosphorus alloy melt, the cooling temperature is 30° C., and cooling for 9 hours to obtain a copper-phosphorus alloy cooled to 98° C.

[0053] Example 2

[0054] This embodiment is basically the same as Embodiment 1, except that: Step 1: adjusting the induction frequency of the vacuum induction furnace to 500 Hz, maintaining 500 Hz for 1 second, and then adjusting the induction frequency of the vacuum induction furnace to 2000 Hz, maintaining 2000 Hz for 1 second; repeating the above operation 7 times to obtain a copper-phosphorus alloy melt.

[0055] Example 3

[0056] This embodiment is basically the same as Embodiment 1, except that: Step 1: adjusting the induction frequency of the vacuum induction furnace to 500 Hz, maintaining 500 Hz for 10 s, and then adjusting the induction frequency of the vacuum induction furnace to 2000 Hz, maintaining 2000 Hz for 10 s; repeating the above operation 7 times to obtain a copper-phosphorus alloy melt.

[0057] Example 4

[0058] This embodiment is basically the same as Embodiment 1, except that: Step 1: adjusting the induction frequency of the vacuum induction furnace to 700 Hz, maintaining 700 Hz for 5 s, and then adjusting the induction frequency of the vacuum induction furnace to 2500 Hz, maintaining 2500 Hz for 5 s; repeating the above operation 7 times to obtain a copper-phosphorus alloy melt.

[0059] Example 5

[0060] This embodiment is basically the same as Embodiment 1, except that: Step 1: adjusting the induction frequency of the vacuum induction furnace to 300 Hz, maintaining 300 Hz for 5 s, and then adjusting the induction frequency of the vacuum induction furnace to 2300 Hz, maintaining 2300 Hz for 5 s; repeating the above operation 7 times to obtain a copper-phosphorus alloy melt.

[0061] Example 6

[0062] This embodiment is basically the same as Embodiment 1, except that: Step 1: The induction frequency of the vacuum induction furnace is adjusted to 2000 Hz to treat the copper-phosphorus melt in the vacuum induction furnace, and the first induction frequency is maintained for 5 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 500 Hz, and the second induction frequency is maintained for 5 seconds; the above operation is repeated 7 times to obtain a copper-phosphorus alloy melt.

[0063] Example 7

[0064] This embodiment is basically the same as Embodiment 1, except that: Step 1: The induction frequency of the vacuum induction furnace is adjusted to 500 Hz to treat the copper-phosphorus melt in the vacuum induction furnace, and the first induction frequency is maintained for 5 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 2000 Hz, and the second induction frequency is maintained for 5 seconds; the above operation is repeated 3 times to obtain a copper-phosphorus alloy melt.

[0065] Example 8

[0066] This embodiment is basically the same as Embodiment 1, except that: Step 1: The induction frequency of the vacuum induction furnace is adjusted to 500 Hz to treat the copper-phosphorus melt in the vacuum induction furnace, and the first induction frequency is maintained for 5 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 2000 Hz, and the second induction frequency is maintained for 5 seconds; the above operation is repeated 10 times to obtain a copper-phosphorus alloy melt.

[0067] Example 9

[0068] This embodiment is basically the same as Embodiment 1, except that: Step 1: The induction frequency of the vacuum induction furnace is adjusted to 500 Hz to treat the copper-phosphorus melt in the vacuum induction furnace, and the first induction frequency is maintained for 5 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 2000 Hz, and the second induction frequency is maintained for 5 seconds; the above operation is repeated 15 times to obtain a copper-phosphorus alloy melt.

[0069] Example 10

[0070] This embodiment is basically the same as Embodiment 1, except that: Step 2: The copper-phosphorus alloy melt is cast, and the bottom of the copper-phosphorus alloy melt is cooled by water cooling at a cooling temperature of 30°C. The copper-phosphorus alloy is cooled to 98°C after cooling for 9 hours.

[0071] Embodiment 11

[0072] This embodiment is basically the same as embodiment 1, except that: Step 2: The copper-phosphorus alloy melt is cast, and the periphery of the copper-phosphorus alloy melt is cooled by water cooling at a cooling temperature of 30°C. The copper-phosphorus alloy is cooled to 98°C after cooling for 9 hours.

[0073] Example 12

[0074] This embodiment is basically the same as embodiment 1, except that: Step 2: 85wt% of the copper-phosphorus alloy melt is cast once to obtain a primary casting liquid, and the bottom of the primary casting liquid is cooled by water cooling at a cooling temperature of 30°C for 4 minutes; then the remaining copper-phosphorus alloy melt is cast on the primary casting liquid, and the cooling is continued at a cooling temperature of 30°C for 9 hours to obtain a copper-phosphorus alloy cooled to 98°C.

[0075] Comparative Example 1

[0076] This comparative example is basically the same as Example 1, except that: Step 1: The induction frequency of the vacuum induction furnace is adjusted to 500 Hz to treat the copper-phosphorus solution in the vacuum induction furnace, and the first induction frequency is maintained for 30 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 2000 Hz, and the second induction frequency is maintained for 5 seconds; the above operation is repeated 7 times to obtain a copper-phosphorus alloy melt.

[0077] Comparative Example 2

[0078] This comparative example is basically the same as Example 1, except that: Step 1: The induction frequency of the vacuum induction furnace is adjusted to 500 Hz to treat the copper-phosphorus solution in the vacuum induction furnace, and the first induction frequency is maintained for 5 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 2000 Hz, and the second induction frequency is maintained for 30 seconds; the above operation is repeated 7 times to obtain a copper-phosphorus alloy melt.

[0079] Comparative Example 3

[0080] This comparative example is basically the same as Example 1, except that: Step 1: The induction frequency of the vacuum induction furnace is adjusted to 700 Hz to treat the copper-phosphorus solution in the vacuum induction furnace, and the first induction frequency is maintained for 5 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 1200 Hz, and the second induction frequency is maintained for 5 seconds; the above operation is repeated 7 times to obtain a copper-phosphorus alloy melt.

[0081] Comparative Example 4

[0082] This comparative example is basically the same as Example 1, except that: Step 1: the induction frequency of the vacuum induction furnace is adjusted to 700 Hz to treat the copper-phosphorus solution in the vacuum induction furnace, and the first induction frequency is maintained for 5 seconds, and then the induction frequency of the vacuum induction furnace is adjusted to 1800 Hz, and the second induction frequency is maintained for 5 seconds; the above operation is repeated 7 times to obtain a copper-phosphorus alloy melt.

[0083] The copper-phosphorus alloy is prepared by the processing methods of Examples 1 to 12 and Comparative Examples 1 to 4, respectively. The testing method is as follows: by detecting the P element component at different radial and longitudinal points of the copper-phosphorus alloy, the phosphorus content in the copper-phosphorus alloy is detected, and the phosphorus mass percentage range is compared. If the phosphorus mass percentage range is large, the uniformity of the copper-phosphorus alloy is poor; if the phosphorus mass percentage range is small, the uniformity of the copper-phosphorus alloy is good, and the phosphorus mass percentage range reflects the uniformity of the copper-phosphorus alloy. The utilization rate of the copper-phosphorus alloy is measured by measuring the ratio of the weight of the usable copper-phosphorus alloy to the total weight of the prepared copper-phosphorus alloy.

[0084] The results are shown in Table 1:

[0085] Table 1 Test results of copper-phosphorus alloy

[0086]

[0087] Result analysis:

[0088] It can be seen from Examples 1-3 that when the first induction frequency and the second induction frequency are maintained for 1 to 10 seconds, the phosphorus content of the copper-phosphorus alloy fluctuates relatively little and has good uniformity.

[0089] It can be seen from Examples 1, 4, and 5 that the phosphorus content of the copper-phosphorus alloy fluctuates relatively little and has good uniformity. However, the copper-phosphorus alloy of Examples 4 and 5 has better uniformity than that of Example 1. Therefore, the frequency difference between the first induction frequency and the second induction frequency is at least 1500 Hz. However, since the induction frequency of the vacuum induction furnace has an upper and lower limit, the frequency difference between the first induction frequency and the second induction frequency is 1500 to 2200 Hz.

[0090] It can be seen from Examples 1 and 6 that the first induction frequency and the second induction frequency are just defined names, and the first induction frequency and the second induction frequency can be 300-700 Hz and 1800-2500 Hz, respectively.

[0091] It can be seen from Examples 1, 7, 8, and 9 that the phosphorus mass percentage range of the copper-phosphorus alloy fluctuates relatively little, and the uniformity of the copper-phosphorus alloy is relatively good. In the range of 3 to 10 times, as the number of repeated operations increases, the uniformity of the copper-phosphorus alloy gradually improves. Moreover, according to the phosphorus mass percentage range of Examples 8 and 9, after repeating the operation 10 times and 15 times, the phosphorus mass percentage range is basically the same. Therefore, for higher efficiency, step 1 is repeated 3 to 10 times.

[0092] It can be seen from Examples 1, 10, and 11 that the utilization rate of the copper-phosphorus alloy in Example 10 is significantly higher than that in Example 1. During casting, Example 10 adopts the method of cooling the bottom of the copper-phosphorus solution, so that the copper-phosphorus solution is cooled from bottom to top instead of from outside to inside, which reduces shrinkage holes and improves the utilization rate of the copper-phosphorus alloy. Moreover, according to the results of Example 11, the utilization rate of the copper-phosphorus alloy is slightly reduced by cooling the periphery of the copper-phosphorus solution.

[0093] It can be seen from Examples 1 and 12 that the utilization rate of the copper-phosphorus alloy in Example 12 is significantly improved. The reason is that secondary casting and cooling of the bottom of the primary casting liquid are adopted. Cooling the bottom of the primary casting liquid can accelerate the cooling of the primary casting liquid, and can enable the primary casting liquid to be cooled from bottom to top, thereby reducing shrinkage cavities. Secondary casting is then used to supplement the shrinkage of the top of the primary casting liquid, further reducing shrinkage cavities, thereby improving the utilization rate of the copper-phosphorus alloy.

[0094] Compared with Comparative Examples 1 and 2, Example 1 has significantly better uniformity than Comparative Examples 1 and 2. In Comparative Example 1, the maintenance time of the first induction frequency is increased to 30 s, while in Comparative Example 2, the maintenance time of the second induction frequency is increased to 30 s. Regardless of whether the maintenance time of the first induction frequency or the second induction frequency is too long, the uniformity of the copper-phosphorus alloy is poor. The reason is that the induction frequency is maintained for too long, resulting in insufficient tumbling and stirring of the copper-phosphorus alloy solution, resulting in poor uniformity.

[0095] Compared with Comparative Examples 3 and 4, Example 1 has a significantly better uniformity than Comparative Examples 3 and 4, indicating that when the frequency difference between the first induction frequency and the second induction frequency is lower than 1500Hz, the switching of the first induction frequency and the second induction frequency cannot improve the uniformity of the copper-phosphorus alloy. Moreover, according to the phosphorus mass percentage range of Comparative Examples 3 and 4, as long as the frequency difference between the first induction frequency and the second induction frequency is lower than 1500Hz, the uniformity of the copper-phosphorus alloy is similar. The reason why Example 1 has a relatively better uniformity is that since the metal solution has viscosity, the first induction frequency and the second induction frequency can only be effective when the frequency is at least 1500Hz, and the stirring effect is generated on the copper-phosphorus solution, so that the uniformity of the copper-phosphorus alloy is improved.

[0096] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for preparing a copper-phosphorus alloy, characterized in that: By converting and adjusting the first induction frequency and the second induction frequency of the vacuum induction furnace, the copper-phosphorus melt in the vacuum induction furnace is caused to oscillate during the frequency conversion process between the first induction frequency and the second induction frequency, and then the copper-phosphorus alloy is cast; the frequency difference between the first induction frequency and the second induction frequency is at least 1500 Hz, and the maintenance time of the first induction frequency and the second induction frequency is respectively 1 to 10 seconds.

2. The method for preparing a copper-phosphorus alloy according to claim 1, characterized in that: The frequency difference between the first induction frequency and the second induction frequency is 1500-2200 Hz.

3. The method for preparing a copper-phosphorus alloy according to claim 1, characterized in that: The first induction frequency is 300-700 Hz; the second induction frequency is 1800-2500 Hz.

4. The method for preparing a copper-phosphorus alloy according to claim 1, characterized in that: The frequency conversion times between the first induction frequency and the second induction frequency is 3 to 10 times.

5. The method for preparing a copper-phosphorus alloy according to claim 1, characterized in that: The copper-phosphorus melt is prepared by the following steps: Step a: placing copper in a vacuum induction furnace and heating it to obtain copper melt; Step b: introducing a protective gas into the vacuum induction furnace until the gas pressure in the vacuum induction furnace is 20-50 kPa, adding a copper-phosphorus master alloy, keeping the temperature and standing to obtain a copper-phosphorus melt; the copper-phosphorus master alloy has a phosphorus content of 5-15wt%, and the balance is copper; the copper-phosphorus melt has a phosphorus content of 0.04-0.065wt%, and the balance is copper.

6. The method for preparing a copper-phosphorus alloy according to claim 5, characterized in that: The heating temperature of step a is 1100-1300° C., the heating time is 15-45 min, and the vacuum degree is 0.01-1 Pa.

7. The method for preparing a copper-phosphorus alloy according to claim 5, characterized in that: The insulation temperature of step b is 1100-1300° C. and the standing time is 10-50 minutes.

8. The method for preparing a copper-phosphorus alloy according to claim 1, characterized in that: The steps include: Step 1: adjusting the induction frequency of the vacuum induction furnace to a first induction frequency to treat the copper-phosphorus molten liquid in the vacuum induction furnace, maintaining the first induction frequency for 1 to 10 seconds, and then adjusting the induction frequency of the vacuum induction furnace to a second induction frequency, maintaining the second induction frequency for 1 to 10 seconds; repeating the above operation 3 to 10 times to obtain a copper-phosphorus alloy molten liquid; The phosphorus content in the copper-phosphorus melt is 0.04-0.065wt%, and the balance is copper; Step 2: Casting to obtain copper-phosphorus alloy.

9. The method for preparing a copper-phosphorus alloy according to claim 8, characterized in that: The step 2 is specifically as follows: casting the copper-phosphorus alloy melt and cooling the bottom of the copper-phosphorus alloy solution at a cooling temperature of 10 to 50° C. for a cooling time of 1 to 8 minutes; reducing the copper-phosphorus alloy melt to below 100° C. within 11 hours to obtain the copper-phosphorus alloy.

10. The method for preparing a copper-phosphorus alloy according to claim 8, characterized in that: The step 2 specifically comprises: casting 70-95wt% of the copper-phosphorus alloy melt once to obtain a primary casting liquid, cooling the bottom of the primary casting liquid at a cooling temperature of 10-50°C for a cooling time of 1-8 minutes; then casting the remaining copper-phosphorus alloy melt on the primary casting liquid, reducing the temperature of the copper-phosphorus alloy melt to below 100°C within 11 hours, and obtaining a copper-phosphorus alloy.

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