Standard Group will now elaborate on aging test and inspection methods.
1. UV Fluorescent Ultraviolet Aging Test Method
(1) Fluorescent ultraviolet lamps are low-pressure mercury lamps with a wavelength of 254nm. The addition of phosphorus coexistence substances converts them to longer wavelengths. The energy distribution of fluorescent ultraviolet lamps depends on the emission spectrum generated by the phosphorus coexistence substances and the transmission properties of the glass tube. These lamps have specific spectral segments. Currently, there are two types available: UVA (351, 340) and UVB (313 and F40). The UVA-340 lamp closely simulates the short-wave ultraviolet spectrum of sunlight, with an energy distribution closely resembling the solar spectrum from 360nm, making it more representative of natural sunlight. UVA is preferred for its closer resemblance to natural exposure. UVB accelerates material degradation more rapidly. The inherent spectral stability of fluorescent ultraviolet lamps simplifies irradiance control. Their spectral energy distribution remains constant over time, unlike xenon arc lamps mentioned earlier. This feature enhances the reproducibility of test results. The primary advantage of using ultraviolet lamps for aging tests lies in their condensation process, which simulates the damaging effects of outdoor humidity on materials. To date, there is no international consensus on the optimal light source for artificial accelerated aging. Western European countries recommend xenon arc lamps for their superior simulation capabilities, while the United States and Japan hold differing views.
(2) UV fluorescent lamp equipment can simulate various environmental conditions, including day and night cycles, temperature variations, humidity, water spray, and different lamp types. Compared to carbon arc lamps, UV fluorescent lamps better simulate the ultraviolet portion of sunlight, although they artificially enhance the spectral energy in the ultraviolet range. Due to their ability to rapidly assess material resistance to aging, UV fluorescent lamp aging tests are still widely adopted in numerous standards.
Equipment Used: UV ultraviolet aging test chamber
2. Thermal Aging Test Method
(1) Thermal aging tests accelerate the aging process of materials under the combined effects of oxygen and heat, reflecting their resistance to thermal-oxidative aging. Oven aging tests are a common method for evaluating heat resistance, with the test temperature determined based on material requirements and experimental objectives. The upper temperature limit can be established according to relevant technical specifications. Generally, for thermoplastic materials, it should be below the Vicat softening point, and for thermosetting materials, below the heat distortion temperature. Alternatively, temperatures that do not cause sample decomposition or significant deformation can be selected through preliminary experiments. Samples are placed in a thermal oven under specified conditions, and their appearance and performance are periodically inspected and tested to evaluate their heat resistance. This method is commonly used for plastics, rubber, and heat-resistant tests for information recording media. The prevailing test methods include the thermal air exposure test for plastics, accelerated thermal aging and heat resistance tests for vulcanized or thermoplastic rubber, and heat resistance tests for paint films.
Equipment Used: High-temperature aging test chamber
3. Xenon Lamp Accelerated Aging Test Method
(1) Xenon lamp light sources are considered the most effective in simulating the full solar spectrum. Xenon lamp spectra contain ultraviolet wavelengths shorter than those cut off by solar radiation, which can be filtered out. Furthermore, xenon lamp light sources enable automatic control of light intensity, temperature, light/dark cycles, and humidity, simulating and intensifying environmental factors such as light, heat, air, temperature, humidity, and rain that primarily cause aging damage to polymer materials in natural climates. This allows for rapid simulation of sunlight exposure effects under various climates, yielding weather resistance data closely resembling natural climate conditions. Currently, artificial accelerated aging tests using xenon lamps have become a preferred and widely used method for light aging tests, resulting in numerous corresponding xenon lamp aging test methods.
Equipment Used: Xenon lamp aging tester
4. High-Pressure Accelerated Aging Test Method
(1) High-pressure aging chambers accelerate performance tests on products under high-temperature, high-humidity, and high-pressure climatic conditions during storage, transportation, and use. They are primarily used for testing electrical and electronic products, components, parts, metal materials, and other substances under simulated high-temperature, high-humidity, and high-pressure conditions. These tests evaluate the physical and other related properties of products. After testing, product performance is verified to determine if it meets requirements, facilitating product design, improvement, verification, and pre-delivery inspections.
Equipment Used: HAST (Highly Accelerated Stress Test) chamber, PCT (Pressure Cooker Test) chamber
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