Accelerated weathering test method for plastics,coatings and rubber materials used for machinery industrial products
Some standard content:
National Standard of the People's Republic of China
Accelerated weathering test method for plastics, coatings and rubber materials used for machinery industrial products
Accelerated weathering test method for plastics, coatings and rubber materials used for machinery industrial productsGB/T14522-93
The artificial weathering (xenon lamp) exposure test method specified in this standard refers to the content of the xenon lamp light source in ISO4892-82 "Plastic Laboratory Light Source Test Method" of the International Organization for Standardization. 1 Subject content and scope of application
This standard specifies two artificial weathering accelerated test methods that simulate the main factors in the outdoor hot and humid natural atmosphere: a. Fluorescent ultraviolet/condensation test method (hereinafter referred to as fluorescent ultraviolet method); b. Artificial weathering (xenon lamp) exposure test method (hereinafter referred to as xenon lamp method). This standard is applicable to the comparison of the outdoor weathering resistance (hereinafter referred to as weathering resistance) of different types of plastics, coatings and rubber materials used for machinery industrial products or materials of the same type with different formulations; it can also be used for quality grade assessment tests of known weathering materials. For general tests, the fluorescent UV/condensation test method can be used; if necessary, the artificial climate (xenon lamp) exposure test method can be used for verification and comparison tests.
The test results of this standard cannot simply and directly infer the service life of the material. Note: This method quotes the technical content of the plastic xenon lamp light source exposure test method in GB9344. 2 Terminology
2.1 Test of fluorescent UV-Condensation typ A test that uses a fluorescent UV lamp as a light source to simulate and intensify the UV spectrum that has the most significant effect on the degradation of polymer materials, and appropriately controls the temperature and humidity to produce condensation on the sample periodically. 2.2 Test of exposure to artificial weathering (xenon arc lamp as light source) A test that uses a xenon lamp as a light source to simulate and intensify the sunlight spectrum reaching the ground, and appropriately controls the temperature, humidity and water spraying conditions. 2.3 Ultraviolet regions Ultraviolet regions UV-A wavelength range is 315~400nm; UV-B wavelength range is 280~315nm, UV-C wavelength <280nm.
2.4 Fluorescent UV lamp is a low-pressure mercury lamp with a wavelength of 254nm. Due to the addition of phosphorus coexistence, it is converted into a longer wavelength. The energy distribution of the fluorescent UV lamp depends on the emission spectrum produced by the phosphorus coexistence and the diffusion of the glass tube. 2.5 Irradiance
The total amount of incident radiation of all wavelengths, expressed in W/m2. Because the radiation is distributed according to different wavelengths, the photochemical effects caused by different spectra are very different, so different lamp sources should not be used for comparison. 2.6 Spectral irradiance spectral irradiance is the function of irradiance with wavelength, expressed in W/m2 for each wavelength band. Usually, the irradiance of sunlight is expressed in W/m2 for each 10nm wavelength band, while the ultraviolet fluorescent lamp is expressed in 1 or 2nm. Spectral irradiance is a suitable method for comparing light sources with different energy distributions. 2.7 Spectral energy distribution spectral energy distribution is a characteristic curve that represents the amount of irradiance at each wavelength. It can be expressed in W/m2 according to power or in J according to energy. This characteristic curve should include the wavelength range of all incident light, while fluorescent ultraviolet lamps are usually expressed in relative spectral energy base distribution, which is expressed as the percentage of the irradiance at each wavelength compared to the peak value (see Figure 3).
3 Test equipment
3.1 Fluorescent UV test
3.1.1 The structure of the test chamber is made of corrosion-resistant metal materials and includes 8 fluorescent UV lamps, a water tray, a test sample rack, and a temperature and time control system and indicator (see Figure 1).
Control device
Indoor air cooling
Test sample
Water heater
Heated water
Ultraviolet lamp (off)
Test sample
Door that opens upwards
Oxygen channel
Figure 1 Sectional view of the structure of the fluorescent UV/condensation test chamber 3.1.2 The fluorescent UV lamp should start quickly, the lamp power is 40W, the lamp length is 1220mm, and the uniform working area of the test chamber is 900×210 mm (see Figure 2).
Area of uniform ultraviolet intensity
Figure 2 Range of uniform irradiation area of the test chamber
3.1.3 Unless otherwise specified, the wavelength of the fluorescent ultraviolet lamp is 280~315nm, that is, the UV-B wavelength range, and the characteristics of relative spectral irradiance (see Figure 3).
GB/T 14522-93
Wavelength, nm
Figure 3 Relative spectral irradiance of UV-B fluorescent ultraviolet lamp3.1.4 The lamps are installed in a row of four and two rows. The lamps in each row are installed in parallel, and the center distance of the lamps is 70mm (see Figure 1). 3.1.5 The test sample should be fixedly installed at a position 50mm away from the nearest parallel surface of the lamp surface (see Figure 1). The test sample and its support form the inner wall of the box, and their backs are exposed to the cooling air at room temperature. Due to the temperature difference between the test sample and the air in the box, the condensation stage on the surface of the test sample produces stable condensation conditions. The test box should produce natural air convection from the bottom through the outer wall of the box and the channel of the test sample. 3.1.6 Water vapor is generated by the water tray at the bottom of the heating box. The water depth is not more than 25mm, and there is an automatic water supply controller. The water tray should be cleaned regularly to prevent scale formation.
3.1.7 The temperature of the test box is measured by a sensor fixed on a black aluminum plate with a width of 75mm, a height of 100mm, and a thickness of 2.5mm (hereinafter referred to as the blackboard). The blackboard should be placed in the central area of the exposure test. The measurement range of the thermometer is 30~80C, with a tolerance of ±1C. The control of the light and condensation stages should be carried out separately. The condensation stage is controlled by the heating water temperature. 3.1.8 The test box should be placed in a test room with a temperature of 15 to 35°C, 300mm away from the wall, and should be protected from the influence of other heat sources. The air in the test room should not be strongly circulated to avoid affecting the lighting and condensation conditions. 3.2 Xenon lamp artificial climate test
3.2.1 The wavelength range of the light emitted by the xenon lamp is from below 270mm to the infrared region. The xenon lamp should be properly filtered and effectively cooled to filter out shorter wavelength rays and more infrared rays, so that the spectrum reaching the surface of the test sample is similar to the sunlight spectrum reaching the ground. 3.2.2 The test box is equipped with a rotating bracket to drive the sample to rotate. The temperature, humidity, water spraying time and xenon lamp power should be adjustable, and there is an automatic recording device for dry and wet bulb temperatures. The dry and wet bulb temperature sensors should be placed in a dark place. According to needs, a power regulator can be prepared outside the box, and a heater can be installed inside the box. In order to reduce the pollution of the xenon lamp cooling water to the lamp and the filter cover, the cooling water is distilled water or deionized water, and the cooling water pipe is made of water-resistant corrosion materials, such as stainless steel, plastic, etc. Aluminum, copper, iron and bronze should be avoided. 3.2.3 The sample rack should be made of inert materials, such as aluminum alloy, stainless steel or wood, and bronze, copper and iron components should be avoided near the sample.
4 Test conditions
4.1 Fluorescent ultraviolet test
4.1.1 The test sample is fixed on the sample rack, facing the fluorescent lamp. When the sample does not completely fill the sample rack, the blackboard is used to fill the sample rack and keep the inner wall of the test box closed. 4.1.2 Test temperature. Three temperatures of 50, 60 and 70℃ can be used during illumination. 60℃ is preferred; the temperature of the condensation stage is 50℃. The tolerance of the source temperature is ±3C.
4.1.3 The cycle of illumination and condensation can be selected as 4h illumination, 4h condensation or 8h illumination, 4h condensation. 4.1.4 After 400~450h of illumination, each row of lamps needs to be replaced with a fluorescent lamp, and the other lamps are switched as shown in Figure 4. The effective life of the lamp is 1600~1800h.
GB/T14522---93
4.1.5 When replacing the lamp, the water tray should be wiped dry and cleaned to avoid the formation of scale. Poly
New lamp
Figure 4 Schematic diagram of fluorescent lamp conversion
4.2 Artificial climate test of fluorescein lamp
New lamp
4.2.1 The radiation intensity is 1000±200W/m2 in the wavelength range of 300～890nm, and should not exceed 1W/m2 below 300nm; in the area where the test sample is hung, the deviation should be less than 10%. 4.2.2 The temperature of the test chamber is measured by the blackboard, and the blackboard temperature is 63±3℃. It can also be 55±3℃ or a temperature higher than 63℃ as needed, but a higher temperature may produce a thermal aging effect and affect the test results. The temperature of the blackboard should be measured when it reaches a stable reading without spraying water. 4.2.3 The relative humidity can be selected from three conditions: 65%±5%, 50%±5% or 90%±5%. The relative humidity should be measured when it reaches a stable reading without spraying water. 4.2.4 The water spraying cycle can be selected to spray water for 18 minutes every 102 minutes or spray water for 12 minutes every 48 minutes. 4.2.5 During use, the xenon lamp and filter cover will gradually age, deposit scale or other reasons, causing the irradiation intensity to decrease. Therefore, light energy monitoring must be carried out. When measuring light energy, the photoreceptor should be fixed at the same position as the test sample to receive light energy. When the measured light energy does not meet the test requirements, the xenon lamp power should be adjusted. If necessary, the xenon lamp and filter cover should be cleaned. The xenon lamp and filter cover have a certain lifespan and should be replaced after a certain period of use as required. 5 Test cycle
The following test cycles are recommended for the two test methods: 4, 7, 14, 21, 28, 42, 63, and 84 days. According to the performance change rate of the test sample, the test cycle can be appropriately changed. The final deadline can be determined based on the test sample performance change reaching the specified value, which is generally not more than 105 days.
6 Test samples
Generally, standard samples should be prepared according to the relevant regulations based on the performance to be measured. Paint test samples should be manufactured into 75mm×150mm×1.0～1.5mm. For example, when testing mechanical properties, the test samples should be sufficient in number to ensure that the expected test results can be achieved. The two test methods also have the following requirements: 6.1 Fluorescent ultraviolet testbZxz.net
GB/T 14522-—93
6.1.1 The maximum thickness of the test sample should not exceed 20mm to ensure sufficient heat exchange to produce condensation on the test sample. 6.1.2 For strip test samples such as plastics and rubber, they should be fixed on aluminum alloy or other base plates with good corrosion resistance and heat transfer. 6.1.3 For paint test samples on steel base plates, the rust on the edges should not stain the surface of the test sample. 6.1.4 Holes larger than 1mm on the test sample should be sealed to prevent water vapor from escaping. 6.2 Xenon lamp test
The test sample should not be subjected to external stress on the sample rack. In order to avoid different light intensity on the surface due to different exposure positions of the test sample, when installing the test sample, it should be reasonably arranged and fixed on the rotating bracket according to the size and shape of the test sample, and the position can be changed, such as changing the upper and lower rows, turning 180° on the spot, changing the upper and lower rows, turning 180° on the spot, and the four steps constitute an exchange cycle. In an exchange cycle, the exchange time of each step is equal. 7 Performance evaluation of test samples
7.1 Appearance evaluation
For coatings, the main thing is to evaluate the appearance. Plastics and rubber can also be evaluated for appearance when necessary. The main items to be checked are gloss, color change (color difference), chalking, spots, blistering, cracks and dimensional stability. Instruments should be used as much as possible to perform quantitative project tests, such as gloss and color difference.
7.2 Evaluation of mechanical properties and other properties
Generally, rubber materials are tested for tensile strength, elongation, and hardness, and plastics are tested for impact strength, elongation at break, tensile strength, and bending strength. Other performance test items may be specified if necessary. 8 Test report
Test method
Fluorescent ultraviolet test or xenon lamp test;
b. Test conditions
Lighting time, condensation or water spraying time and corresponding temperature, humidity, spectrum of fluorescent ultraviolet lamp or irradiation intensity during xenon lamp test; test cycle;
Name and model of test material;
Size and preparation method of test sample;
f. Test equipment
Equipment model, specifications, jaw lamp and filter cover type during rat lamp test, g.
Test results;
h. Test date and personnel.
Additional notes:
This standard is proposed by the Ministry of Machinery and Electronics Industry of the People's Republic of China. This standard is under the jurisdiction of Guangzhou Electric Science Research Institute of the Ministry of Machinery and Electronics Industry. This standard was drafted by Guangzhou Electric Science Research Institute of the Ministry of Machinery and Electronics Industry. The main drafters of this standard are Liang Xingcai, Gao Renzhi and Pan Huisheng. The fluorescent ultraviolet/condensation test method specified in this standard refers to the American Society for Testing and Materials ASTMG53-84 "Non-metallic Material Xiluo Fluorescent Ultraviolet/Condensation Test Method". 7942 Evaluation of mechanical properties and other properties
-Generally, rubber materials are tested for tensile strength, elongation, and hardness; plastics are tested for impact strength, elongation at break, tensile strength, and bending strength. Other performance test items may be specified if necessary. 8 Test report
Test method
Fluorescent ultraviolet test or xenon lamp test;
b. Test conditions
Lighting time, condensation or water spraying time and corresponding temperature, humidity, spectrum of fluorescent ultraviolet lamp or irradiation intensity during xenon lamp test; test cycle;
Name and model of test material;
Size and preparation method of test sample;
f. Test equipment
Equipment model, specifications, jaw lamp and filter cover type during rat lamp test; g.
Test results;
h. Test date and personnel.
Additional notes:
This standard is proposed by the Ministry of Machinery and Electronics Industry of the People's Republic of China. This standard is under the jurisdiction of Guangzhou Electric Science Research Institute of the Ministry of Machinery and Electronics Industry. This standard was drafted by Guangzhou Electric Science Research Institute of the Ministry of Machinery and Electronics Industry. The main drafters of this standard are Liang Xingcai, Gao Renzhi and Pan Huisheng. The fluorescent ultraviolet/condensation test method specified in this standard refers to the American Society for Testing and Materials ASTMG53-84 "Non-metallic Material Xiluo Fluorescent Ultraviolet/Condensation Test Method". 7942 Evaluation of mechanical properties and other properties
-Generally, rubber materials are tested for tensile strength, elongation, and hardness; plastics are tested for impact strength, elongation at break, tensile strength, and bending strength. Other performance test items may be specified if necessary. 8 Test report
Test method
Fluorescent ultraviolet test or xenon lamp test;
b. Test conditions
Lighting time, condensation or water spraying time and corresponding temperature, humidity, spectrum of fluorescent ultraviolet lamp or irradiation intensity during xenon lamp test; test cycle;
Name and model of test material;
Size and preparation method of test sample;
f. Test equipment
Equipment model, specifications, jaw lamp and filter cover type during rat lamp test; g.
Test results;
h. Test date and personnel.
Additional notes:
This standard is proposed by the Ministry of Machinery and Electronics Industry of the People's Republic of China. This standard is under the jurisdiction of Guangzhou Electric Science Research Institute of the Ministry of Machinery and Electronics Industry. This standard was drafted by Guangzhou Electric Science Research Institute of the Ministry of Machinery and Electronics Industry. The main drafters of this standard are Liang Xingcai, Gao Renzhi and Pan Huisheng. The fluorescent ultraviolet/condensation test method specified in this standard refers to the American Society for Testing and Materials ASTMG53-84 "Non-metallic Material Xiluo Fluorescent Ultraviolet/Condensation Test Method". 794
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