Two exposure methods of small ultraviolet aging test chamber
November 16, 2021 05:23AM
Two exposure methods of small ultraviolet aging test chamber

When the small ultraviolet aging test box is used for aging test, the surface temperature of the sample is an important exposure parameter. Generally, high temperature will accelerate the polymer degradation process. The allowable test temperature should be determined according to the tested material and the aging performance evaluation index. Fluorescent ultraviolet lamps emit less infrared rays than xenon lamps and carbon arc lamps, and the heating effect on the surface of the sample is basically formed by the convection of hot air. Therefore, the temperature difference between the blackboard thermometer, the black standard thermometer, the surface of the sample and the air in the exposure chamber is very small.

In this regard, we can adopt the following two exposure methods, or other methods, but the exposure conditions should be stated in the test conditions.

1. After the sample has been exposed to light for a period of time, it is followed by a non-irradiation period (when the temperature changes and condensation is formed on the sample) cyclic test. The test period is in accordance with relevant standards. If there is no specified cycle condition, the following cycle is recommended:

Exposure to radiation at a black standard temperature of 60℃±3℃ for 4h or 8h, then, exposure to condensation without radiation at a black standard temperature of 50℃±3℃ for 4h.

Note: The aging degradation of some polymers (such as PVC) is very sensitive to temperature. In this case, it is recommended to use a radiation exposure temperature below 60°C (such as 50°C) to simulate a colder climate.

When the radiation exposure followed by condensation exposure is selected, the allowable radiation or condensation exposure period is as short as 2 hours to ensure that the conditions of each exposure period reach equilibrium.

2. The sample is continuously exposed to radiation and has a cycle test of regular water spray. Relevant standards and regulations during the trial period. If not specified, the following test conditions are recommended: irradiate for 5h at a black standard temperature of 50℃±3℃ and air relative humidity (10±5)﹪, and then continue to irradiate at a black standard temperature of 20℃±3℃ Expose and spray water for 1h.

Comfortable Thermal Manikin
Male car driving warm body dummy
Automotive test dummies
Sorry, only registered users may post in this forum.

Click here to login