Artificially accelerated aging experiment and natural aging experiment in UV aging test chamber

In general, the industry requires rapid aging test results and at the same time a good correlation between the artificial accelerated aging test results and the natural laboratory aging test results, but in fact these two requirements are mutually exclusive. contradictory. The artificial accelerated aging method uses a higher test temperature, a shorter wavelength light source and a greater radiation intensity than the actual environment. While accelerating the aging process of materials, it reduces the correlation with the aging results of natural conditions.

Main parameters of UV aging test chamber:

01. Light source: lamp wavelength: UVA-340/UVB-313; Number of lamps: 8; Lamp power: 40W/piece;

02. Simulated environment: temperature, humidity, light, spray, condensation;

03 .Temperature range: RT+10℃～70℃;

04. Humidity range: ≥95%RH;

05. Temperature variation: ≤±0.5℃;

06. Temperature uniformity: ≤ ±2℃;

07. Board temperature: 40℃~65℃;

08 Tube spacing: 35mm;

09. Test time: 1~9999S, M, H adjustable;

10. Number of samples: about 40 pieces;

11. Irradiance range: <50W/㎡.

The UVA-340 lamp tube equipped with the UV aging test chamber offers a new solution plan. UVA-340 ultraviolet light source can well simulate the short wave ultraviolet light (<365nm part) in the solar spectrum. Since the short-wave ultraviolet light from the sun simulated by the UVA-340 ultraviolet light source is usually the main cause of polymer damage, the test results of this method theoretically have a better correlation with outdoor natural aging. Our company Shanghai QINSUN Precision Electromechanical Technology Co., Ltd. can provide UV aging testing machine and custom welcome those in need to inquire. To verify this, we performed a series of experiments on the correlation between natural outdoor exposure and artificial accelerated aging using a UVA-340 ultraviolet light source.

In this experiment, epoxy coatings, polyurethane coatings and polyester coatings were selected for outdoor natural exposure and artificial ultraviolet accelerated aging experiments, and the changes in gloss and color of the samples were recorded in the experiments .

Experiment with outdoor natural exposure

Since the conditions for outdoor natural exposure are very different in different places, it is an accurate evaluation of the experiment, three different typical climate types: subtropicalh climate (Miami, Florida), desert climate (Phoenix, Arizona) and northern industrial climate (Cleveland, Ohio).

Outdoor natural exposure is strictly in accordance with ASTM G7 Non-metallic Materials Outdoor Natural Exposure Test Standard. The back plate of the tested sample is a 1.6 mm thick splint and the sample holder is 45°, facing south.

Artificial Accelerated Aging Test

The Artificial Accelerated Aging Test is performed in accordance with ASTM G154 Ultraviolet Aging Test Method for Non- metallic materials. The experimental equipment is a UV accelerated aging testing machine. The test box has a closed-loop feedback loop system control, which can set and control the UV light irradiation intensity. The test uses a UVA-340 ultraviolet lamp with a maximum light intensity of 343 nm and a cut-off point of 295 nm. To avoid the influence of different temperaturen To eliminate the experimental results, the test temperature was uniformly set at 50°C.

The experiment was tested under three different cycle conditions:

Condition 1: 4 hours of UV light irradiation, 4 hours condensation; The irradiance point of the UVA-340 lamp is controlled at 0.83W/(m2·nm)@340nm; the tempThe temperature of the entire test cycle is controlled at 50°C. The UV radiation intensity in this test cycle is equivalent to the sunlight at noon in summer.

Condition 2: 4 hours of ultraviolet light irradiation, 4 hours of condensation; the irradiance point of the UVA-340 lamp is controlled at 1.35W/(m2 nm)@340nm; throughout the test cycle. The temperature was maintained at 50°C. Condition 2 is basically similar to condition 1, but the irradiation is stronger.

Condition 3: 4 hours of UV radiation (100% UV radiation, no condensation, no dark cycle); the irradiation point of the UVA-340 lamp is regulated at 1.35W/(m2 nm)@340nm; the temperature of the entire test cycle is controlled at 50°C.