3Wear resistance test research

3.1Research Objective

Study the results of sand dropping, sandblasting, and abrasion tests to determine the appropriate methods and indicator requirements for wear resistance testing.

3.2Test operation

3.2.1Samples produced simultaneously under the same process conditions should be subjected to wear resistance tests using the sand dropping method (comparing silicon carbide and standard sand abrasives, and grinding simultaneously), sandblasting method, and abrasion method. It is recommended to perform wear resistance tests for each method5-10Analyze the deviation of the results obtained by each method using individual samples.

3.2.1Take coatings with different colors and powder sizes (including sand and smooth surfaces) and conduct wear resistance tests using sand dropping method, sandblasting method, and abrasion method respectively. Analyze the results to determine the wear resistance index requirements (this test should include high-performance powder coatings).

3.2.3Determination of wear resistance of coatings by falling sand method

according toGB5237.4-2004AppendixAThe test shall be conducted in accordance with the provisions of the "Sand Drop Test Method".

3.2.4Determination of wear resistance of coatings by sandblasting method

adoptGB/T12967.1-1991Anodizing of Aluminum and Aluminum Alloys The average wear resistance of anodic oxide film shall be measured using a spray abrasion tester in accordance with the regulations.

3.2.5Determination of wear resistance of coatings by abrasion method

according toGB/T1768-79The test shall be conducted in accordance with the provisions of the "Determination Method for Wear Resistance of Paint Films". During the experiment, set the total conversion to1000Rotation speed is60turn/Minutes, with a load capacity of500gram.

3.2.６The sand dropping method can explore the use of two types of abrasives, silicon carbide and standard sandConduct experiments and compare their results.

4Experimental study on salt spray corrosion performance

4.1Research Objective

Determine whether to classify and index the salt spray corrosion resistance of ordinary and high-performance powder coatings.

4.2Test operation

4.2.1Neutral salt spray test

4.2.1.1Test Method

In150㎜×75Draw two intersecting lines deep to the metal substrate along the diagonal of the mm sample, without passing through the diagonal. The endpoints of each line should be equidistant from the corresponding diagonal, and then follow theGB/T10125Conduct experiments according to the corresponding regulations. When the experimental time reaches1500hIn the future, every500hThe sample should be inspected once on both sides (the inspection interval can be adjusted according to the actual situation), and the total testing time should reach4000h.

4.2.1.2Performance Requirements

Neutral salt spray test on test plates with cross scratches（NSSAfter the experiment, first mark both sides of the cross line2.0Visually inspect the parts beyond mm, and there should be no corrosion on the coating. press againGB/T9286-1998in7.2.6According to the regulations, the test should be conducted at a distance from the marked line2.0There should be no coating peeling off outside the millimeter.

4.2.2Acetic acid salt spray test

4.2.2.1Test Method

In150mmx75mmDraw two intersecting lines along the diagonal of the sample that are deep enough to the metal substrate. The line segments do not run through the diagonal, and the endpoints of the line segments are equidistant from the corresponding diagonal. Then, pressGB/T10125Regulations for conducting experiments. Test time reached750After hours, every120The sample should be inspected once every hour or so (the inspection interval can be adjusted according to the actual situation during the test).

4.2.1.2Performance Requirements

Coating treated with acetate salt spray(ASS)After the experiment, the single-sided permeation under the membrane on both sides of the line should be marked≤4mmAt the same time, the surface of the non marked area is pressedGB/T6461The regulations are rated based on their protection levelR≥9.5Grade. The defect area generated in the non marked area after the experiment and the corresponding protection level classification are shown in the table1.

table1

Percentage of defect area to sample area%	level
0	10
≤0.02	9.8
>0.02~0.05	9.5
>0.05~0.07	9.3
>0.07~0.10	9
>0.10~0.25	8

4.2.3Copper accelerated acetate salt spray test

4.2.3.1Test Method

Coated copper accelerated acetate salt spray test according toGB/T10125Regulations are in place. The sample size is150mmx75mmWhen the experimental time reaches96hIn the future, every24The sample should be inspected once every hour or so (the inspection interval can be adjusted according to the actual situation during the test).

4.2.3.2Performance Requirements

Copper accelerated acetate salt spray test for coating after specified time(CASSexperiment)Afterwards, its protection levelR≥9.5Grade. The evaluation of test results shall be based onGB/T6461The regulations are in place. The area of defects generated after the experiment and the corresponding classification of protection levels are shown in the table2.

table2

Percentage of defect area to sample area%	level
0	10
≤0.02	9.8
>0.02~0.05	9.5
>0.05~0.07	9.3
>0.07~0.10	9
>0.10~0.25	8

5Research on Heat and Moisture Resistance Test

5.1Research Objective

By conducting long-term moisture resistance tests on ordinary performance coatings and high-performance powder coatings, the grading criteria for moisture resistance performance are determined.

5.2Test operation

5.2.1Test Method

Coating moisture resistance test according toGB/T1740Regulations are in place. Test time: Ordinary performance powder coating≥1500hHigh performance powder coating≥3000hThe test time should be extended to4000hOr conduct the experiment until there are abnormalities (changes beyond the first level range) in samples of the same type.

5.2.2Performance Requirements

After the coating undergoes a moisture and heat resistance test, its changes should≤1Grade.

6 ISO11341Research on Standard Methods

6.1Research Objective

By comparing the versionISO11341Conduct research, identify differences, and apply methods for experimentation.

6.2 ISO11341-2004The main experimental parameters are as follows：

Select radiation flux to ensure the average irradiance of the test panel rack planeE：

——method1——In300nm～400nmBetween them, it is60W/m²Or in340nmWhen is0.51W/（m².nm）．

——method2——In300nm～400nmBetween them, it is50W/m²Or in420nmWhen is1.1W/（m².nm）．

Wetting time:18min

Drying time:102min

Relative humidity during drying period:40%～60%

Black standard temperature:65⁰C±2⁰C

Test chamber temperature:38⁰C±3⁰C

Deionized water conductivity:≤2us

6.3 ISO11341-1994The main experimental parameters are as follows:

Select the radiation flux so that the test panel rack plane is in290nmto800nmThe average irradiance between wavelengths is550W/m².

Wetting time:18min

Drying time:102min

Relative humidity during drying period:60%～80%

Black standard temperature:65⁰C±2⁰C

Deionized water conductivity:≤2us

6.4 Test operation

6.4.1Test Method

Compare high-performance powder coating samples with ordinary performance powder coating samples according toISO11341-2004Conduct experiments using standard methods. Test time: Ordinary performance powder coating500h，750h，1000hHigh performance powder coating1000h，1500h，2000h，3000h，4000h(The experimental time can be adjusted according to the actual situation during the experiment).

6.4.2Performance Requirements

The evaluation of test results shall be based onGB/T1766The regulations are in place. After the artificial accelerated aging test with xenon lamp irradiation for a specified time, the coating should not produce powdering phenomenon0Level, with a minimum of level 1 loss of light and color difference.

6.4.3carry out1000 hxenon + AASsTest, evaluate the marked area and sample surface after the test.

7 Machu Test Research

7.1Research Objective

Evaluate the resistance to filamentous corrosion under the coating film by studying the results of the Machu test.

7.2Test operation

7.2.1Test Method

• Along the diagonal of the sample (sample size is75mm×150mm）Draw two intersecting lines deep into the metal substrate, without passing through the diagonal of the specimen. The endpoints of each line should be equidistant from the corresponding diagonal, and then follow the table3Conduct experiments to check the degree of unilateral permeation under the membrane.

Test fluid and conditions	Concentration and related parameters
Sodium chloride（NaCl）	50g/L±1 g/L
Glacial acetic acid（CH3COOH）	10ml/L±1 ml/L
Hydrogen peroxide（30%H2O2）	5 ml/L±1 ml/L
temperature	370C±10C
Test time	48h±0.5h

BThe solutionPHThe value is3.0-3.3.24hIn the future, join again5 ml/LHydrogen peroxide（H₂O₂30%）Adjust with glacial acetic acid or sodium hydroxidePHValue, continue testing until48hA new solution should be prepared for each experiment.

7.2.2Performance Requirements

After the test, the unilateral penetration on both sides of the coating marking should not exceed0.5mm.

8 SO₂experimental study

8.1Research Objective

Testing the corrosion resistance of the coating by using a humid atmosphere with sulfur dioxide.

8.2Test operation

8.2.1Test Method

AAlong the diagonal of the specimen (specimen size is75mm×150mm）Draw two intersecting lines deep into the metal substrate, without crossing the diagonal of the specimen. The endpoints of each line should be equidistant from the corresponding diagonal.

• In300L±10LIn the airtight container of dissolution, the passage is as follows0.2LSulfur dioxide, in40⁰C±3⁰CAt temperature, to24hFor one cycle, according toGB/T9789Conduct experiments. The number of test cycles is determined by the actual situation of the sample.

8.2.2Performance Requirements

After the coating undergoes a corrosion resistance test against sulfur dioxide in humid atmosphere, the surface of the sample should be visually inspected and there should be no color changes or bubbles. The single-sided permeation under the membrane on both sides of the line shall not exceed1mm.

9“Anti sawing, anti drilling, etc”Performance test research

9.1Research Objective

Study the anti sawing performance of the coating.

9.2Test operation

9.2.1Test Method

Suitable for using aluminum profiles/Sharp tools are used to saw and drill aluminum profiles for testing.

9.2.2performance evaluation

Qualified when the coating has no cracks or fractures;

When the coating cracks or fractures, it is not qualified.