The main reasons for aging of materials such as plastic coatings are climate and sun exposure.For many manufacturers attach great importance to the product's aging resistance and light resistance. These two factors directly determine the manufacturer's product life. Therefore, the methods and equipment for testing the product's aging behavior must have been widely developed and applied. The two derived Two test methods: more natural Exposure test and artificial accelerated aging test. Due to the limitations of natural exposure test, the most widely used method is artificial accelerated aging test, and the test equipment developed is UV aging test chamber and xenon lamp aging test chamber.
TheUV aging test chamber is used to test many products , this product is more sensitive to the long wavelength band of ultraviolet rays, visible light and infrared rays. The aging test is carried out by simulating light, high temperature and humidity through the appropriate control of the device.
But the UV aging test chamber cannot simulate the full spectrum sunlight . Their tenet is that for long-lasting materials exposed outdoors, the most important cause of aging damage is the short-wavelength range of UV radiation from 300-400 nm. In the short-wavelength range of UV radiation, i.e. from 365 nm to the lowest band of the Sunlight, Ultraviolet A weathering chamber simulates sunlight very well, but cannot do much at longer wavelengths.
The UV aging test chamber manufactured by our company uses two kinds of lamps are tested, UVA-340 and UVB lamps, have UVA-340 lamps a good effect in simulating the ultraviolet shortwave band of sunlight, and its spectral power distribution (SPD) is in the region of the limit point of sunlight to about 360 nm.The solar spectrum fits very well.UV-B lamps are also widely used in UV aging test chambers They cause materials to age faster than UV-A tubes, but the number of wavelengths shorter than the sun's limit can produce unrealistic results for many materials, so we generally recommend customers to use UVA-340 ultraviolet lamps (imported and domestic) customers can choose to use) for the aging test.
The test method huhWhen selecting equipment, customers should select the appropriate test equipment according to the product or material being tested, final application conditions, and budget.
Appendix: The difference between UV lamps and fluorescent lamps
Ultraviolet lamps use low-pressure mercury vapor to produce UV rays of 254nm and 185nm, but the outer envelope is made of fused silica and there is no phosphor on the glass envelope. For example, UV germicidal lamps use UV rays to sterilize bacteria directly, so the light it emits is ultraviolet light, the sterilization consists of using ultraviolet light with wavelengths of 254nm and 185nm. In addition, our UVA-340 lamp tube is used in the UV aging test chamber test, which uses UV rays with ewith a wavelength of 340 nm as a light source for accelerated aging. The light they emit should be invisible ultraviolet rays, but for protection reasons, some industries that use ultraviolet rays still make products that emit blue-violet light for warning and protection.
Fluorescent lamps are low-pressure mercury lamps, such as fluorescent lamps and energy-saving lamps etc. It uses low-pressure mercury vapor to emit ultraviolet rays during the discharge process. Low-pressure mercury vapor mainly produces 254nm and 185nm ultraviolet rays, so the phosphor emits visible light, so it belongs to the low-pressure arc discharge light source. The lighting mechanism shows that fluorescent powder plays a key role in the quality of fluorescent lampsmus read of fluorescent lamps: The tubes of fluorescent lamps and energy-saving lamps are made of ordinary glass, which cannot penetrate ultraviolet rays and emits visible light after being absorbed by fluorescent powder. It is visible light, not ultraviolet light. The reason why it is sometimes called ultraviolet fluorescent lamp is mainly because it is excited by ultraviolet light.
So both use low-pressure mercury vapor to emit ultraviolet rays during the discharge process Radiate out, but usage is different due to the different way the shell is penetrated.