Method for preparing beryllium-copper master alloy by recycling waste beryllium material

Abstract

The invention discloses a method for preparing beryllium-copper master alloy by recycling waste beryllium materials, and belongs to the technical field of beryllium-copper alloy, the method comprises the following steps: S1, sequentially carrying out acid pickling, water washing, ultrasonic cleaning, spin-drying and drying on waste beryllium chips and beryllium-copper leftover materials; s2, according to the beryllium content in the beryllium-copper master alloy, weighing the dried beryllium scraps and beryllium-copper leftover materials, and putting the beryllium scraps and the beryllium-copper leftover materials into a cake pressing machine for pressing to obtain columnar materials; and S3, the columnar material is placed in a copper crucible in a vacuum suspension smelting furnace, and water cooling, vacuumizing, argon filling, power regulation and control smelting, staged cooling, vacuum breaking and surface cleaning are sequentially carried out. The beryllium-copper master alloy prepared through the method is stable in beryllium content control and low in impurity content, recycling of beryllium waste and beryllium-copper leftover materials is achieved, and the production cost of the beryllium-copper alloy is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of beryllium copper alloys, and in particular relates to a method for preparing a beryllium copper master alloy by recycling waste beryllium materials. Background Art

[0002] Beryllium copper alloy refers to a solid solution copper-based alloy containing 0.2-2.8wt% beryllium. It is the "king of elasticity" among copper alloys. After solution aging heat treatment, it can obtain products with high strength and high conductivity. High-strength cast beryllium bronze alloy, after heat treatment, not only has high strength and high hardness, but also has the advantages of wear resistance and corrosion resistance. It has excellent casting properties. Beryllium bronze alloy is suitable for manufacturing various molds, explosion-proof safety tools, wear-resistant parts such as cams, gears, wheels, bearings, etc. This alloy has good mechanical properties and corrosion resistance, and is widely used in aerospace, equipment manufacturing and other fields.

[0003] At present, the preparation process of beryllium copper master alloy is mainly divided into non-vacuum ingot casting and vacuum ingot casting. The non-vacuum ingot casting methods used in the actual production of beryllium copper alloy include tilted iron mold ingot casting, flowless ingot casting, semi-continuous ingot casting and continuous ingot casting. The first two methods are only used in factories with smaller production scales. In order to obtain beryllium copper alloy ingots with low gas content, small segregation, small inclusions, and uniform and dense crystal structure, the best way is to perform vacuum ingot casting after vacuum refining. Vacuum ingot casting has a significant effect on ensuring the content of easily oxidized elements such as beryllium and titanium. If necessary, inert gas can be introduced to protect the ingot casting process. Through vacuum smelting, the purity of beryllium copper master alloy can be effectively improved on the basis of reducing environmental pollution.

[0004] With the growing demand for beryllium copper alloy, the cost of preparing beryllium copper master alloy with traditional raw materials continues to increase, the supply of raw materials is becoming increasingly tight, and the waste scraps generated during the processing of beryllium materials and beryllium copper continue to accumulate and are difficult to consume. At the same time, due to the increasing oxygen content in the waste scraps, the traditional smelting process cannot fully dissolve the waste scraps, and it is difficult to prepare a beryllium copper master alloy with a beryllium content of 10%, which makes it difficult to accurately control the content of the components in the finished master alloy. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing beryllium copper master alloy by recycling waste beryllium materials. The beryllium copper master alloy prepared by the method has high beryllium content, stable control and low impurity content, realizes the recycling and reuse of beryllium waste materials and beryllium copper scraps, and reduces the production cost of beryllium copper alloy.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for recycling waste beryllium material to prepare beryllium-copper master alloy, the method comprising:

[0008] Step S1, pickling, water washing, ultrasonic cleaning, drying and drying the waste beryllium cuttings and beryllium copper scraps in sequence;

[0009] Step S2, according to the beryllium content in the beryllium copper master alloy, weigh the dried waste beryllium cuttings and beryllium copper scraps, and put them into a cake press to press them to obtain columnar materials;

[0010] Step S3, placing the columnar material in a copper crucible in a vacuum suspension melting furnace, and sequentially performing water cooling, vacuuming, argon filling, power regulation melting, staged temperature reduction cooling, vacuum breaking and surface cleaning;

[0011] In step S3, the specific process of the power regulation smelting is:

[0012] At a speed of 18-22kw / min, adjust the power from 0kw to 260kw, and melt at a constant temperature for 5-8min; at a speed of 8-12kw / min, adjust the power from 260kw to 340kw, and melt at a constant temperature for 10-15min;

[0013] In step S3, the specific process of the staged cooling is as follows:

[0014] According to the cooling rate of 20-35℃ / min, after cooling to 400℃, adjust the power to 0kw and cool for 35-40min.

[0015] Furthermore, in the step S1, the pickling acid is nitric acid with a concentration of 5 to 7%, and the time is 1.8 to 2.2 hours;

[0016] In the step S1, the cleaning solution for ultrasonic cleaning is an alkaline cleaning solution with a concentration of 40-55%, and the time is 1.6-2.2 hours.

[0017] Furthermore, in the step S1, the water washing is performed 4 to 5 times.

[0018] Furthermore, in the step S1, the rotation speed of the spin drying is 480-520 rpm;

[0019] In the step S1, the drying temperature is 140-160°C and the drying time is 10-12 hours.

[0020] Furthermore, in the step S2, the pressing pressure is 30 to 50 tons, and the pressing time is 5 to 10 minutes.

[0021] Further, in the step S2, the beryllium content in the beryllium copper master alloy is 9.5-10.5%;

[0022] The beryllium content in the beryllium copper scraps is 1 to 3%;

[0023] The waste beryllium cuttings and beryllium copper scraps are in the shape of cuttings.

[0024] Furthermore, in step S3, the water cooling time is 3 to 5 minutes.

[0025] Furthermore, in step S3, the vacuum degree after evacuation is 4.5 to 6.5×10 -3 Pa.

[0026] Furthermore, in step S3, the pressure after filling with argon is -45 to -55 Pa.

[0027] In summary, the technical solution of the present invention has the following technical effects:

[0028] The invention presses waste beryllium cuttings and beryllium copper scraps into columnar materials, which is beneficial to the heat transfer of the copper crucible in the vacuum suspension smelting process, accelerates the dissolution of the waste beryllium cuttings and beryllium copper scraps, ensures the full dissolution of the waste beryllium cuttings and beryllium copper scraps, avoids the waste beryllium cuttings condensing on the surface and being difficult to dissolve, and improves the uniformity of the structure and composition of the beryllium copper master alloy; through power regulation and smelting, part of the metal impurities in the beryllium copper master alloy are effectively removed, and the impurity content in the beryllium copper master alloy is reduced; the beryllium copper master alloy of the invention has uniform structure and composition, stable beryllium content control, beryllium content of 9.5-10.5%, low impurity content, excellent performance of the beryllium copper master alloy, simple process, easy operation, realizes the recycling and reuse of waste beryllium and beryllium copper scraps, and reduces the production cost of the beryllium copper alloy. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Embodiment 1:

[0031] Step S1, put the scrap beryllium chips and beryllium copper scraps into a 6% nitric acid pickling tank, soak for 2 hours, wash with clean water 4 times, then put them into an ultrasonic cleaning tank and use 50% SK-202 oil cleaning agent to circulate and clean for 2 hours, then spin dry the raw materials at a speed of 500 rpm, put them into an oven, and dry them at a temperature of 150°C for 11 hours.

[0032] Step S2: According to the beryllium copper master alloy with a beryllium content of 10.2%, the dried waste beryllium cuttings and beryllium copper scraps with a beryllium content of 2% are weighed, and put into a cake press, and pressed for 8 minutes with a pressure of 40 tons to obtain a 50mm*60mm columnar material.

[0033] Step S3: Place the columnar material in a copper crucible in a vacuum suspension smelting furnace, close the suspension furnace door, turn on the control cabinet power, turn on the air compressor, turn on the automatic vacuum, turn on the crucible and coil circulating water, turn on the water cooler, and after water cooling for 4 minutes, turn on the vacuum gauge and wait for the vacuum to be evacuated to 6×10 -3 Pa; turn off the vacuum gauge, close the main pumping valve, continue to fill the melting furnace with argon to -50Pa, close the charging valve, start the melting furnace control cabinet, and perform power regulation melting, staged cooling, vacuum breaking and surface cleaning in sequence.

[0034] Among them, the specific process of power regulation smelting is:

[0035] At a speed of 20kw / min, adjust the power button from 0kw to 260kw, the material begins to melt, keep the power unchanged, and melt for 6 minutes; at a speed of 10kw / min, adjust the power button from 260kw to 340kw, and melt at a constant temperature for 12 minutes to dissolve the solid solution remaining in the melt, until the raw material is completely melted, and the melt presents a uniform and transparent sphere that turns at a uniform speed in the crucible;

[0036] The specific process of staged cooling is as follows:

[0037] According to the cooling rate of 30℃ / min, adjust the power button until the temperature drops to 350℃, then adjust the power to 0kw. The melt is formed after cooling in the crucible for 37 minutes. Turn off the power of the control cabinet and turn off the power switch.

[0038] Breaking the vacuum: After the smelting is completed, turn off the vacuum pump, Roots pump and molecular pump, close the front stage valve, open the vent valve, and break the vacuum to a non-vacuum state.

[0039] The Be content in the beryllium copper master alloy of this embodiment is 10.2wt%, and the Cu content is 89.7wt%. After testing the processed rod with a diameter of 70mm, the tensile strength can reach 573Mpa and the elongation can reach 28.4%, both of which are higher than the standard value (400Mpa / 20%).

[0040] Embodiment 2:

[0041] Step S1, put the scrap beryllium chips and beryllium copper scraps into a 7% nitric acid pickling tank, soak for 2.2 hours, wash with clean water for 5 times, then put them into an ultrasonic cleaning tank and use HY-1163C alkaline cleaning solution with a concentration of 55% for 2.2 hours of circulation cleaning, then, spin dry the raw materials at a speed of 520rpm, put them into an oven, and dry them at a temperature of 160°C for 10 hours.

[0042] Step S2: According to the beryllium copper master alloy with a beryllium content of 10.5%, the dried waste beryllium cuttings and beryllium copper scraps with a beryllium content of 3% are weighed, and put into a cake press, and pressed for 10 minutes with a pressure of 50 tons to obtain a 45mm*65mm columnar material.

[0043] Step S3: Place the columnar material in a copper crucible in a vacuum suspension melting furnace, close the suspension furnace door, turn on the control cabinet power, turn on the air compressor, turn on the automatic vacuum, turn on the crucible and coil circulating water, turn on the water cooler, and after water cooling for 5 minutes, turn on the vacuum gauge and wait for the vacuum to be evacuated to 6.5×10 -3 Pa; turn off the vacuum gauge, close the main pumping valve, continue to fill the melting furnace with argon to -55Pa, close the charging valve, start the melting furnace control cabinet, and perform power regulation melting, staged cooling, vacuum breaking and surface cleaning in sequence.

[0044] Among them, the specific process of power regulation smelting is:

[0045] At a speed of 22kw / min, adjust the power button from 0kw to 260kw, the material begins to melt, keep the power unchanged, and melt for 8 minutes; at a speed of 12kw / min, adjust the power button from 260kw to 340kw, and melt at a constant temperature for 15 minutes to dissolve the solid solution remaining in the melt, until the raw material is completely melted, and the melt presents a uniform and transparent sphere that turns at a uniform speed in the crucible;

[0046] The specific process of staged cooling is as follows:

[0047] According to the cooling rate of 35℃ / min, adjust the power button until the temperature drops to 380℃, then adjust the power to 0kw. The melt is formed after cooling in the crucible for 40min. Turn off the power of the control cabinet and turn off the power switch.

[0048] Breaking the vacuum: After the smelting is completed, turn off the vacuum pump, Roots pump and molecular pump, close the front stage valve, open the vent valve, and break the vacuum to a non-vacuum state.

[0049] The Be content in the beryllium copper master alloy of this embodiment is 10.5wt%, and the Cu content is 89.4wt%. After testing the processed rod with a diameter of 70mm, the tensile strength can reach 575Mpa and the elongation can reach 32%, both of which are higher than the standard value (400Mpa / 20%).

[0050] Embodiment 3:

[0051] Step S1, put the scrap beryllium chips and beryllium copper scraps into a 5% nitric acid pickling tank, soak for 1.8 hours, wash with clean water 5 times, then put them into an ultrasonic cleaning tank and use 40% SK-202 oil cleaning agent to circulate and clean for 1.6 hours, then spin dry the raw materials at a speed of 480 rpm, put them into an oven, and dry them at a temperature of 140°C for 12 hours.

[0052] Step S2: According to the beryllium copper master alloy with a beryllium content of 9.5%, the dried waste beryllium cuttings and beryllium copper scraps with a beryllium content of 1% are weighed, and put into a cake press, and pressed for 5 minutes with a pressure of 30 tons to obtain a 52mm*62mm columnar material.

[0053] Step S3: Place the columnar material in a copper crucible in a vacuum suspension smelting furnace, close the suspension furnace door, turn on the control cabinet power, turn on the air compressor, turn on the automatic vacuum, turn on the crucible and coil circulating water, turn on the water cooler, and after water cooling for 3 minutes, turn on the vacuum gauge and wait for the vacuum to be evacuated to 4.5×10 -3 Pa; turn off the vacuum gauge, close the main pumping valve, continue to fill the melting furnace with argon to -45Pa, close the charging valve, start the melting furnace control cabinet, and perform power regulation melting, staged cooling, vacuum breaking and surface cleaning in sequence.

[0054] Among them, the specific process of power regulation smelting is:

[0055] At a speed of 18kw / min, adjust the power button from 0kw to 260kw, the material begins to melt, keep the power unchanged, and melt for 5 minutes; at a speed of 8kw / min, adjust the power button from 260kw to 340kw, and melt at a constant temperature for 10 minutes to dissolve the solid solution remaining in the melt, until the raw material is completely melted, and the melt presents a uniform and transparent sphere that turns at a uniform speed in the crucible;

[0056] The specific process of staged cooling is as follows:

[0057] According to the cooling rate of 20℃ / min, adjust the power button until the temperature drops to 380℃, then adjust the power to 0kw. The melt is formed after cooling in the crucible for 35 minutes. Turn off the power of the control cabinet and turn off the power switch.

[0058] Breaking the vacuum: After the smelting is completed, turn off the vacuum pump, Roots pump and molecular pump, close the front stage valve, open the vent valve, and break the vacuum to a non-vacuum state.

[0059] The Be content in the beryllium copper master alloy of this embodiment is 9.5wt%, and the Cu content is 90.4wt%. After testing the processed rod with a diameter of 70mm, the tensile strength can reach 443.9Mpa, and the elongation can reach 43.2%, both of which are higher than the standard value (400Mpa / 20%).

[0060] Please note that the technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. The above embodiments only express several implementation methods of the present application, and their descriptions are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several variations and improvements can be made, which all belong to the scope of protection of the present application. Therefore, the scope of protection of the patent in this application shall be based on the attached claims.

Claims

1. A method for recovering waste beryllium material to prepare beryllium copper master alloy, characterized in that: The method comprises: Step S1, pickling, water washing, ultrasonic cleaning, drying and drying the waste beryllium cuttings and beryllium copper scraps in sequence; Step S2, according to the beryllium content in the beryllium copper master alloy, weigh the dried waste beryllium cuttings and beryllium copper scraps, and put them into a cake press to press them to obtain columnar materials; Step S3, placing the columnar material in a copper crucible in a vacuum suspension melting furnace, and sequentially performing water cooling, vacuuming, argon filling, power regulation melting, staged temperature reduction cooling, vacuum breaking and surface cleaning; In step S3, the specific process of power regulation smelting is: At a speed of 18-22kw / min, adjust the power from 0kw to 260kw, and melt at a constant temperature for 5-8min; at a speed of 8-12kw / min, adjust the power from 260kw to 340kw, and melt at a constant temperature for 10-15min; In step S3, the specific process of the staged cooling is as follows: According to the cooling rate of 20-35℃ / min, after cooling to 400℃, adjust the power to 0kw and cool for 35-40min.

2. The method according to claim 1, characterized in that In step S1, the pickling acid is nitric acid with a concentration of 5-7%, and the time is 1.8-2.2h; In the step S1, the cleaning solution for ultrasonic cleaning is an alkaline cleaning solution with a concentration of 40-55%, and the time is 1.6-2.2 hours.

3. The method according to claim 2, characterized in that In the step S1, the water washing is performed 4 to 5 times.

4. The method according to claim 3, characterized in that In the step S1, the rotation speed of the spin drying is 480-520 rpm; In the step S1, the drying temperature is 140-160°C and the drying time is 10-12 hours.

5. The method according to any one of claims 1 to 4, characterized in that: In the step S2, the pressing pressure is 30 to 50 tons, and the pressing time is 5 to 10 minutes.

6. The method according to claim 5, characterized in that In the step S2, the beryllium content in the beryllium copper master alloy is 9.5-10.5%; The beryllium content in the beryllium copper scraps is 1 to 3%; The waste beryllium cuttings and beryllium copper scraps are in the shape of cuttings.

7. The method according to claim 6, characterized in that In step S3, the water cooling time is 3 to 5 minutes.

8. The method according to claim 7, characterized in that In step S3, the vacuum degree after evacuation is 4.5 to 6.5×10 -3 Pa.

9. The method according to claim 8, characterized in that In the step S3, the pressure after filling with argon is -45 to -55 Pa.