During the car is in motion, it will face various harsh weather conditions, inevitably resulting in adverse phenomena such as aging and corrosion of component materials, which will affect the appearance and function of the car, and even pose safety hazards. Therefore, analyzing the factors affecting the aging and corrosion of automotive component materials is of great significance for understanding the changes in material properties and proposing countermeasures.
1 The Influence of Natural Light on Automotive Materials
There are many factors that affect natural light on cars, mainly depending on the properties and intensity of light, as well as the type and quality of car materials.
Sunlight radiation can cause attenuation effects on materials and components. The heat generated by sunlight has a certain impact on the operational performance, thermal management, noise, and dimensional stability of automobiles. Usually, after interacting with radiation illuminance, radiation intensity, temperature, moisture, and other environmental effects, it triggers and accelerates material surface degradation, leading to aging of automotive structural components in their original structural positions and assembly methods.
(1) Solar radiation spectrum
Solar radiation has multiple effects on automotive materials, mainly affected by ultraviolet (UV) radiation, thermal radiation, and optical radiation. Research on the aging of automotive interior and exterior and components based on solar radiation spectra is of great significance.
(2) Ultraviolet (UV) radiation
Ultraviolet radiation is a part of sunlight, with a wavelength range of approximately 10-400nm. It can cause paint fading, appearance aging, and damage to plastic and rubber components, making them brittle, cracked, and aged.
Different wavelengths of ultraviolet radiation within the ultraviolet wavelength range have different effects, among which: UV-A band (400-320nm) can cause degradation of certain polymers (plastics or polymer materials); UV-B band (320-280nm): It is the lowest wavelength in natural light and can cause degradation of most polymers; UV-C band (280-200nm): can cause abnormal reactions in polymers.
(3) Thermal radiation
Under solar radiation (the heat energy in solar radiation), automotive materials absorb a portion of the heat energy and then reflect another portion. The absorbed solar heat causes the material to heat up, which also has a certain impact on automotive components, especially in high-temperature weather conditions.
(4) Optical radiation
Visible light is a part of the solar spectrum that includes light within the visible range, which is the light that the human eye can perceive. The wavelength range of visible light ranges from short wavelength purple to long wavelength red. The impact of visible light radiation on automotive components is mainly reflected in the form of thermal energy, which depends on the properties and intensity of light, as well as the type and material of the components.
2 Solar simulation aging technology
Solar simulated aging technology is a method used to simulate solar radiation and meteorological conditions in natural environments. It is widely used in climate and environmental testing for photovoltaics, automobiles, trains, airplanes, as well as in small environmental chambers, building shading research, and other fields to test the performance and durability of materials, products, or components under long-term exposure. This technique is commonly used to evaluate the aging and degradation processes that may occur in materials exposed to outdoor environments, in order to improve product design and material selection.
The standard aims to simulate the exposure of vehicles to natural sunlight during actual use, in order to evaluate the performance, durability, and stability of passenger car grade components and materials.
Automobile Solar Simulated Environment Chamber
The automobile solar simulated environment chamber is a device specifically designed to simulate solar radiation and natural environmental conditions, to test the performance, durability, and aging of automobile components, materials, and the entire vehicle under sunlight exposure, in order to evaluate the performance and reliability of automobiles in high-temperature environments. Generally includes solar simulator, temperature and humidity control system, circulation and spray system, etc.
Solar simulator: a device used to simulate sunlight, generally consisting of components such as a light source, power supply and control circuits, and a computer. Light sources typically use xenon lamps or metal halide lamps as light sources, which can produce light close to the natural spectrum of sunlight, including visible light, ultraviolet (UV), and infrared (IR) radiation, to simulate actual solar radiation conditions. The basic principle of a solar simulator is to use artificial light sources to simulate solar radiation, in order to overcome the disadvantages of solar radiation being affected by time and climate, and the inability to adjust the total irradiance. It is widely used in fields such as automobiles, aerospace, photovoltaics, and agriculture.
Temperature and humidity control system: It can simulate temperature and humidity under different climatic conditions, which helps simulate the exposure of cars in different seasons and geographical locations
Circulation and sprinkler system: It can simulate rainwater erosion and humid conditions to evaluate the waterproof performance of materials and components.
The solar simulator is widely used in material aging performance testing, automotive interior and exterior aging testing, vehicle thermal management solar simulation testing, automotive emission solar simulation testing, environmental wind solar simulation testing, rail transit solar simulation testing, aerospace solar simulation testing, solar cell characteristic testing, special lighting, optoelectronic material characteristic testing, environmental research and other fields.
3 Full spectrum sunlight simulation system
The full spectrum sunlight simulation system is a test chamber used to test the aging performance of automotive components and vehicles under sunlight exposure. By using a sunlight simulation system, users can evaluate the performance changes of components or the entire vehicle after exposure, such as shape, color, glossiness, feel, strength, etc.
There are three main types of light sources for full spectrum solar simulators: full spectrum solar simulation systems, infrared aging simulation systems, and accelerated ultraviolet light simulation systems.
Full spectrum solar simulation system: When used as an experimental light source, it can simulate solar radiation;
Infrared aging simulator: mainly utilizing the photothermal effect of infrared light;
Accelerated UV simulator: mainly utilizes the photochemical effect of UV light.
The three aspects for measuring the technical indicators of a full spectrum solar simulator include:
Spectral distribution: The consistency between the light source and real sunlight can be classified into Class A, Class B, and Class C based on spectral distribution.
Uniformity: The rays emitted by a simulated sunlight source need to have good uniformity, which can be divided into Class A, Class B, and Class C based on uniformity.
Stability: By measuring the light intensity of a full spectrum solar simulator over a period of time, it can be classified into Class A, Class B, and Class C based on stability.
However, the data on total solar radiation, ultraviolet radiation, infrared radiation, and visible light in the atmospheric environmental condition data record table are often inconsistent with the data on total solar radiation, ultraviolet radiation, infrared radiation, and visible light in the component microenvironment data record table. This is because the radiation receiving angle of the radiation sensor monitoring atmospheric environmental conditions is generally horizontal or latitude, and the radiation main receiving angle of specific components on the vehicle is not the same as these angles, requiring the installation of additional radiation sensors for specialized monitoring.
In summary, the automotive sunlight aging simulation technology is a method of evaluating the performance and durability of automotive components, materials, and vehicles under long-term exposure by simulating natural sunlight radiation and meteorological conditions. To assist automobile manufacturers in improving product design, material selection, and quality control, ensuring the performance and reliability of automobiles in various natural environments.