Model :TSA013D
Uv accelerated weathering tester can simulate the harm caused by sunlight and dew. The equipment uses ultraviolet lamps to simulate the effect of sunlight exposure, condensates moisture to simulate rain and dew, and the material to be measured is placed at a certain temperature
The types of hazards tested in alternating light and moisture cycles include: fading, discoloration, loss of light, chalking, cracking and bubbling, brittleness and deterioration of strength and oxidation. Testing can help you select new materials, improve existing materials, and evaluate how changes in formulation affect product durability.
Instrument characteristics
1. Lighting function:
This test box uses ultraviolet light to simulate the harm of sunlight. Although only about 5% of the ultraviolet light in sunlight, it is the main cause of photochemical damage to durable materials exposed outdoors: this is because the photochemical effect of light increases with the reduction of wavelength, so it is not necessary to reproduce full-wavelength sunlight when simulating the harm of sunlight to durable products. Just simulate short wavelength ultraviolet light, since ultraviolet light is diffuse
Therefore, the test chamber can uniformly irradiate the surface of the sample. No need for complicated injection rotation test samples.
Second, condensation effect:
This device uses a unique condensing device to simulate the effect of rain and dew on the surface of the sample. During the condensation cycle, the lower part of a test shell is heated to produce bovine steam, and the hot steam is kept in the test chamber
With 100% relative humidity and a certain temperature rise, the sample forms the side wall of the test box. The cooling effect of ambient air makes the temperature of the test surface lower than that of the steam temperature. Such temperature difference can make the liquid water continuously condense on the test surface during the whole condensation cycle.
The resulting condensed water is very stable, pure distilled water, which does not contain dissolved solids, which helps to reproduce the test results and eliminates the problem of water stains. And, like natural dew, new condensation
The water is saturated with dissolved oxygen, so it must be very erosive.
Another advantage of this unique condensation system is that instead of using distilled or deionized water for testing, the chamber can use ordinary tap water, which is automatically distilled during evaporation and then condensed onto the sample.
The wetting cycle of this test chamber usually lasts several hours due to up to 12 hours of wet time per day during outdoor exposure. Please note that the UV exposure and condensation processes in this equipment should be carried out separately, as in Reticuli
It's the same in natural climates.
Third, temperature control:
During the UV cycle, photochemical reactions are usually not sensitive to temperature. But the rate of any subsequent reaction depends on the temperature. The rate of these reactions increases with increasing temperature. Therefore, it is very important to control the temperature during UV exposure. In addition, the temperature of the accelerated aging test must be consistent with the maximum temperature at which the material is directly exposed to sunlight.
In this device, the UV exposure temperature can be set at any temperature between 50 ° C and 80 ° C according to the illumination and the ambient temperature. The UV exposure temperature is regulated by a sensitive thermostat and blast system to make this test possible
The temperature of the test box has excellent uniformity.
4. Wetting cycle period:
The severity of tidal erosion increases with the increase of temperature, so it is indispensable to control the temperature of the wetting cycle. Moreover: to accelerate the test, it is necessary to carry out the wet maximum exposure test at a higher temperature.
The temperature of condensation process in this test chamber can be controlled between 40C and 60℃; The temperature of the condensation process is completely independent of the UV exposure temperature.