Xenon lamp VS UV, did you choose the right equipment for agi
time: 2021-04-07 16:44 click:
Material aging is mainly manifested in discoloration, loss of gloss, strength decrease, cracking, peeling, chalking and oxidation. Although everyone agrees that the weather resistance and light resistance of the product are very important, for the laboratory, should the QUV UV aging test or the Q-SUN xenon lamp aging test be used? But often there is no clue. Light (especially ultraviolet light)
For durable materials, such as most coatings and plastics, short-wave ultraviolet rays are the cause of most polymer aging. However, for materials that are not so durable, long-wave ultraviolet or even visible light can cause serious harm to them.
high temperature
When the temperature rises, the damaging effect of light will also increase. Although the temperature does not affect the main photochemical reaction, it affects the subsequent chemical reaction. The laboratory aging test must provide precise temperature control, and usually accelerate the aging by increasing the temperature.
潮湿
Dew is more harmful than rain, because it adheres to the material for a longer time and forms more serious moisture absorption. However, what cannot be ignored is the thermal shock caused by the sudden temperature drop. For example, when a car's temperature rises on a hot summer day but it suddenly loses heat due to a shower, the rain will cause stress erosion in this case.
Any one of these three factors can cause material aging, and they often occur at the same time, and the damage caused is greater than that caused by any single factor. Therefore, in the laboratory, some materials have good durability under the sole action of light or humidity, but under the synergistic effect of the two, they often fail.
QUV
The QUV ultraviolet aging test box uses fluorescent ultraviolet lamps to simulate the damage of sunlight to durable materials. These tubes are similar in electrical principle to the cool white tubes used for general lighting, but they mainly emit ultraviolet light instead of visible or infrared light.
QUV ultraviolet aging test chamber needs different spectra for different end use conditions, and then choose different types of lamps. Common types of lamps include UVA lamps and UVB lamps. Q-SUN
Q-SUN xenon test chambers are believed to best simulate full-spectrum sunlight because they can generate ultraviolet, visible and infrared light. The spectrum of the xenon lamp is affected by two factors: the filter system and the stability of the light source.
The spectrum produced by the xenon lamp test chamber is full-spectrum sunlight, and different types of glass filters must be used to obtain different spectra. Three types of filters that are commonly used are defined in ASTM G155: daylight, window glass, and UV stretch filters.
Daylight filter: usually recommended to study the correlation with natural aging
2. Window glass filter: The spectrum produced by it is very similar to the spectrum of the sun through the glass, and it is often used to test indoor light stability.
3. UV stretch filter: often used to provide faster test results.
Outdoors, the material is wet for 12 hours a day due to dew. In order to simulate outdoor moisture erosion more realistically. QUV uses a special condensation function to reproduce outdoor dew and moisture.
Q-SUN
Most xenon lamp test chambers simulate the effects of humidity through water spray or humidity control systems. Compared with the condensation function, water spray is better in simulating thermal shock and mechanical erosion.
QUV/se The price of the UV aging test box and the Q-SUN Xe-1 xenon lamp aging test box are similar, but their sample capacities are quite different. The QUV UV aging test chamber is approximately 5 times the capacity of the Q-SUN Xe-1. The capacity of the QUV UV aging test box is also larger than that of the Q-SUN Xe-3. The sample capacity of the Q-SUN Xe-3 xenon lamp aging test box is only 72% of that of the QUV.
QUV The UV aging test box can be installed with relatively thin plates or samples. The Q-SUN xenon lamp aging test box can test the types of samples more flexible. In addition to testing flat samples, it can also test three-dimensional parts, test tubes and glass dishes.
Standard reference should be an important consideration in your choice of test equipment. QUV UV aging test chamber and Q-SUN aging test chamber have different standard application scopes. The following table briefly lists the standard requirements of the two equipment. Going back to the original question, should the UV accelerated aging tester be used as a xenon lamp test chamber for the weathering test of materials?
There is no one testing technique that can meet all materials and application conditions. The method you choose depends on your test purpose, what changes to focus on, timing, budget, etc.
