Evaluation method for degreasing performance of neutral degreasing liquid for copper alloy materials

Abstract

The present invention discloses a method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials, the evaluation method comprising the following steps: (1) preparing a test piece from a copper alloy sample with oil; (2) configuring the neutral degreasing liquid to be tested into a solution with a mass fraction of 3.5-4.5% using deionized water, and adjusting its pH value to 8-9; (3) soaking the test piece in the degreasing liquid, then taking it out for rinsing, placing the cleaned test piece vertically, observing and recording the proportion of the water film area on the surface of the test piece to the total immersed area; (4) evaluating the degreasing performance of the degreasing liquid according to the ratio of the water film area on the surface of the test piece to the total immersed area; the evaluation method can accurately evaluate the degreasing ability of the neutral degreasing liquid, and the evaluation result has high reliability. This evaluation method and the evaluation result can provide guidance for the selection of the neutral degreasing liquid, and facilitate the selection of a suitable neutral degreasing liquid during the degreasing process.

Description

Technical Field

[0001] The invention belongs to the technical field of degreasing liquid, and in particular relates to a method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials. Background Art

[0002] In the process of copper alloy material processing and production, the surface of the material is inevitably stained with anti-rust oil, rolling oil and other oils. The traditional degreasing process uses strong acid or strong alkali degreasing liquid for degreasing.

[0003] Traditional acidic and alkaline degreasing liquids often pollute the environment and may corrode materials. In addition, some oils currently used are mineral oils, which cannot undergo saponification reaction with alkalis. In this case, neutral degreasing liquids are still needed to achieve the purpose of degreasing. Neutral degreasing agents are being used more and more widely.

[0004] At present, the detection of neutral degreasing liquid is basically to detect its own performance through specific gravity, ash content, etc., but there is a lack of reliable evaluation method for the degreasing performance of neutral degreasing liquid in the existing technology. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials, and the evaluation method has high reliability.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] A method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials, the evaluation method comprising the following steps:

[0008] (1) Prepare a test piece from a copper alloy sample with oil;

[0009] (2) The neutral degreasing liquid to be tested is prepared into a solution with a mass fraction of 3.5-4.5% using deionized water, and its pH value is adjusted to 8-9;

[0010] (3) Soak the test piece in the degreasing solution, then take it out and rinse it. Place the cleaned test piece vertically and observe and record the proportion of the water film area on the test piece surface to the total immersed area;

[0011] (4) The degreasing performance of the degreasing liquid is evaluated based on the ratio of the water film area on the test piece surface to the total immersed area.

[0012] Furthermore, if the ratio of the total water film area on both sides of the test piece to the total immersed area is ≥80%, the degreasing liquid has excellent oil removal performance; if the ratio of the total water film area on both sides of the test piece to the total immersed area is 40% <80%, the degreasing liquid has qualified oil removal performance; if the ratio of the total water film area on both sides of the test piece to the total immersed area is ≤40%, the degreasing liquid has unqualified oil removal performance.

[0013] In step (1), the oiled copper alloy sample is made into a test piece with a size of 50 mm*70 mm.

[0014] In step (2), a 3% by mass sodium carbonate solution is used to adjust the pH value of the degreasing liquid to 8-9.

[0015] Since the pH value to be adjusted is a weak alkaline requirement, sodium carbonate solution or sodium bicarbonate solution can be used for adjustment. Strong alkaline solution is difficult to control during the process, and it is not recommended to use strong alkaline solution to adjust the pH. The present invention is mainly used to evaluate the degreasing performance of neutral degreasing liquid, and is used to distinguish it from the currently popular strong alkaline degreasing agent, and use weak alkaline conditions to improve the degreasing conditions.

[0016] In step (3), the test piece is placed in the degreasing liquid along the long side direction and immersed for 30-40 seconds.

[0017] In step (3), the test piece is taken out after immersion and rinsed with deionized water for 20 to 25 seconds.

[0018] In step (3), the test piece is placed vertically for 15-20 seconds.

[0019] The neutral degreasing liquid is any degreasing liquid used for cleaning copper alloy strips.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention provides a method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials, which can accurately evaluate the degreasing ability of the neutral degreasing liquid, and the evaluation result is highly reliable. The evaluation method and the evaluation result can provide guidance for the selection of the neutral degreasing liquid, and facilitate the selection of a suitable neutral degreasing liquid during the degreasing process. DETAILED DESCRIPTION

[0022] The present invention is described in detail below with reference to the embodiments.

[0023] Example 1

[0024] A method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials, the evaluation method comprising the following steps:

[0025] (1) The oiled copper alloy specimen was made into a 50 mm*70 mm test piece;

[0026] (2) The neutral degreasing liquid to be tested is prepared into a solution with a mass fraction of 3.5-4.5% using deionized water, and its pH value is adjusted to 8-9 using 3% sodium carbonate solution;

[0027] (3) Soak the test piece in the degreasing solution for 30-40 seconds, then take it out and rinse it with deionized water for 20-25 seconds. Place the cleaned test piece vertically for 15-20 seconds, and observe and record the proportion of the water film area on the test piece surface to the total immersed area;

[0028] (5) The degreasing performance of the degreasing liquid is evaluated based on the ratio of the water film area on the test piece surface to the total immersed area. If the ratio of the total water film area on both sides of the test piece to the total immersed area is ≥80%, the degreasing performance of the degreasing liquid is excellent; if 40% < the ratio of the total water film area on both sides of the test piece to the total immersed area <80%, the degreasing performance of the degreasing liquid is qualified; if the ratio of the total water film area on both sides of the test piece to the total immersed area is ≤40%, the degreasing performance of the degreasing liquid is unqualified.

[0029] Example 2

[0030] A method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials, the evaluation method comprising the following steps:

[0031] (1) The oiled copper alloy specimen was made into a 50 mm*70 mm test piece;

[0032] (2) The neutral degreasing liquid A to be tested is prepared into a solution with a mass fraction of 3.5% using deionized water, and its pH value is adjusted to 8 using a sodium carbonate solution with a mass concentration of 3%;

[0033] (3) The test piece was immersed in the degreasing liquid for 30 seconds, then taken out and rinsed with deionized water for 20 seconds. The cleaned test piece was placed vertically for 15 seconds, and the ratio of the water film area on the test piece surface to the total immersed area was observed and recorded. The ratio of the total water film area on both sides of the test piece to the total immersed area was 75%, indicating that the degreasing performance of the degreasing liquid was qualified.

[0034] Neutral degreasing liquid A is used to degrease and clean the oily copper alloy strip. The degreasing and cleaning process and specific operations are as follows: 1. Prepare a 3.5% concentration of neutral degreasing liquid A, and adjust the pH value to 8; 2. Adjust the production line speed to ensure that the copper alloy strip passes through the degreasing tank for 30 seconds; 3. Turn off the air-drying system of the production line, and count the area of ​​the water film formed on the surface of the material after cleaning at the winding position. After degreasing and cleaning, the area of ​​the water film formed on the upper and lower surfaces of a distance is counted. Since the production line is a horizontal line, it can be clearly found that the water film area on the upper surface is larger than the water film area on the lower surface, but the ratio of the overall water film area to the passing area is about 73%. It can be seen that the actual degreasing effect of neutral degreasing liquid A is consistent with the evaluation results of neutral degreasing liquid A in this embodiment.

[0035] Example 3

[0036] A method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials, the evaluation method comprising the following steps:

[0037] (1) The oiled copper alloy specimen was made into a 50 mm*70 mm test piece;

[0038] (2) The neutral degreasing liquid B to be tested is prepared into a solution with a mass fraction of 4.0% using deionized water, and its pH value is adjusted to 9 using a sodium carbonate solution with a mass concentration of 3%;

[0039] (3) The test piece was immersed in the degreasing solution for 40 seconds, then taken out and rinsed with deionized water for 20 seconds. The cleaned test piece was placed vertically for 20 seconds, and the ratio of the water film area on the test piece surface to the total immersed area was observed and recorded. The ratio of the total water film area on both sides of the test piece to the total immersed area was 87%, indicating that the degreasing solution had good oil removal performance.

[0040] Neutral degreasing liquid B is used to degrease and clean the oily copper alloy strip. The degreasing and cleaning process and specific operations are as follows: 1. Prepare a 4.0% concentration of neutral degreasing liquid B, and adjust the pH value to 9; 2. Adjust the production line speed to ensure that the copper alloy strip passes through the degreasing tank for 40s; 3. Turn off the air-drying system of the production line, and count the area of ​​the water film formed on the surface of the material after cleaning at the winding position. After degreasing and cleaning, count the area of ​​the water film formed on the upper and lower surfaces for a distance. Since the production line is a horizontal line, it can be clearly found that the water film area on the upper surface is larger than the water film area on the lower surface, but the ratio of the overall water film area to the passing area is about 84%. It can be seen that the actual degreasing effect of neutral degreasing liquid B is consistent with the evaluation results of neutral degreasing liquid B in this embodiment.

[0041] Example 4

[0042] A method for evaluating the degreasing performance of a neutral degreasing liquid for copper alloy materials, the evaluation method comprising the following steps:

[0043] (1) The oiled copper alloy specimen was made into a 50 mm*70 mm test piece;

[0044] (2) The neutral degreasing liquid C to be tested is prepared into a solution with a mass fraction of 4.5% using deionized water, and its pH value is adjusted to 9 using a sodium carbonate solution with a mass concentration of 3%;

[0045] (3) The test piece was immersed in the degreasing solution for 35 seconds, then taken out and rinsed with deionized water for 25 seconds. The cleaned test piece was placed vertically for 20 seconds, and the ratio of the water film area on the test piece surface to the total immersed area was observed and recorded. The ratio of the total water film area on both sides of the test piece to the total immersed area was 89%, indicating that the degreasing solution had good degreasing performance.

[0046] Neutral degreasing liquid C is used to degrease and clean the oily copper alloy strip. The degreasing and cleaning process and specific operations are as follows: 1. Prepare a 4.5% concentration of neutral degreasing liquid C, and adjust the pH value to 9; 2. Adjust the production line speed to ensure that the copper alloy strip passes through the degreasing tank for 35 seconds; 3. Turn off the air-drying system of the production line, and count the area of ​​the water film formed on the surface of the material after cleaning at the winding position. After degreasing and cleaning, count the area of ​​the water film formed on the upper and lower surfaces for a distance. Since the production line is a horizontal line, it can be clearly found that the water film area on the upper surface is larger than the water film area on the lower surface, but the ratio of the overall water film area to the passing area is about 88%. It can be seen that the actual degreasing effect of the neutral degreasing liquid C is consistent with the evaluation results of the neutral degreasing liquid C in this embodiment.

[0047] The above-mentioned detailed description of the evaluation method of the degreasing performance of a copper alloy material using a neutral degreasing liquid with reference to the embodiment is illustrative rather than restrictive, and several embodiments can be listed according to the limited scope. Therefore, changes and modifications without departing from the overall concept of the present invention should fall within the scope of protection of the present invention.

Claims

1. A method for detecting the degreasing performance of a neutral degreasing liquid for copper alloy materials, characterized in that: The detection method comprises the following steps: (1) Prepare a test piece from a copper alloy sample with oil; (2) The neutral degreasing liquid to be tested is prepared into a solution with a mass fraction of 3.5-4.5% using deionized water, and its pH value is adjusted to 8-9; (3) Soak the test piece in the degreasing solution, then take it out and rinse it. Place the cleaned test piece vertically and observe and record the proportion of the water film area on the test piece surface to the total immersed area; (4) The degreasing performance of the degreasing liquid is evaluated based on the ratio of the water film area on the test piece surface to the total immersed area.

2. The detection method according to claim 1, characterized in that: If the ratio of the total water film area on both sides of the test piece to the total immersed area is ≥80%, the degreasing performance of the degreasing liquid is excellent; If the ratio of the total water film area on both sides of the test piece to the total immersed area is 40% < 80%, the degreasing performance of the degreasing liquid is qualified; if the ratio of the total water film area on both sides of the test piece to the total immersed area is ≤40%, the degreasing performance of the degreasing liquid is unqualified.

3. The detection method according to claim 1 or 2, characterized in that: In step (1), the oiled copper alloy sample is made into a test piece with a size of 50 mm*70 mm.

4. The detection method according to claim 1 or 2, characterized in that: In step (2), the pH value of the degreasing solution is adjusted to 8-9 using sodium carbonate solution.

5. The detection method according to claim 4, characterized in that: The mass concentration of the sodium carbonate solution is 2-5%.

6. The detection method according to claim 1 or 2, characterized in that: In step (3), the test piece is placed in the degreasing liquid along the long side direction and immersed for 30-40 seconds.

7. The detection method according to claim 1 or 2, characterized in that: In step (3), the test piece is taken out after immersion and rinsed with deionized water for 20 to 25 seconds.

8. The detection method according to claim 1 or 2, characterized in that: In step (3), the test piece is placed vertically for 15-20 seconds.

9. The detection method according to claim 1 or 2, characterized in that: The neutral degreasing liquid is any degreasing liquid used for cleaning copper alloy strips.