Xenon Test Chambers are R&D and quality control tools for testing materials exposed to direct sunlight, sunlight through window panes, or indoor lighting. The aging of materials has always been a concern of people. In daily life, the aging of polymer materials is commonplace.
The aging of polymer materials, including plastics, rubber, fibers, and coatings, mainly refers to the heat, light, oxygen, mechanical stress, ozone, harmful metal ions, and radiation during processing, storage, or use of the material, resulting in physical damage to the material. or chemically change and degrade its performance.
Generally speaking, aging is a process in which the properties of materials change from good to bad. Due to different types of materials and different conditions of use, the aging characteristics of materials are also different.
The aging phenomenon of polymer materials is summarized in the following aspects
Changes in appearance, such as material discoloration, hardening, softening, cracking, etc.;
Changes in physical and chemical properties, such as thermal conductivity, molar mass, solubility, etc.;
Changes in mechanical properties, such as hardness, tensile strength, impact strength, etc.;
Changes in electrical properties, such as dielectric constant, dielectric loss, breakdown voltage, etc.
The laboratory light accelerated aging test is a commonly used aging test method for plastics. Suitable for indoor and outdoor plastics that are often exposed to sunlight or sunlight through window glass for long periods of time. The xenon Test Chamber fully considers the effects of light, oxygen, heat, humidity and rainfall on the appearance and performance of plastics. The spectral energy distribution of xenon arc lamps is very similar to that of sunlight, so it is widely used for the aging of plastics.
For products with complicated shapes and difficult to make standard samples, the main focus is usually to check the appearance of the sample (chalking, discoloration, color difference, etc.). Therefore, the samples should be cut from the same part as much as possible, one of the samples is used as the original comparison sample, and the other samples are used for the xenon lamp aging test.
When placing the sample, the exposed surface of the product should face the xenon light source under actual use conditions. Sheets, films, plates and other products can be cut according to the relevant standards of tensile and tear samples, to measure the changes in mechanical properties before and after aging, and to evaluate the light aging resistance of products. When multiple different samples are subjected to aging test at the same time, the samples that should not be rejected should be marked on the backlight side of the sample to distinguish different samples.
According to the tensile strength test method ISO 13939-1:1999, the change in tensile strength of polyester-cotton fabrics for travel tents after xenon aging was tested in the warp and weft directions. Xenon arc lamp aging conditions comply with ISO 4892-2:2006.
The irradiance at 340nm is 0.50W/m2, the black standard temperature is 65°C, the temperature of the xenon lamp Test Chamber is 38°C, and the relative humidity is 50%. Daylight filter is used, the spray cycle is 102min for drying/18min for spraying, and the light time is 360h. Suitable for interior plastics exposed to sunlight through window panes
Xenon light sources need to be filtered to reduce spectral irradiance below 320nm to simulate daylight filtered through window glass. In addition to undertaking functions such as vibration reduction, heat insulation, and sound absorption, changes in the appearance of automotive interior parts during long-term use will also affect the appearance and image of the car.
Xenon arc lamp aging test, which simulates sunlight passing through the window glass, is used to observe the appearance changes of interior parts, which can provide a test basis for the selection of interior parts.
The xenon arc lamp aging test is carried out under the following test conditions using the air outlet of the instrument panel.
340nm irradiance 0.50W/m2, black mark temperature 63°C, relative humidity 50%, window glass filter, continuous light without spraying, light time 400h.
Using a xenon lamp aging box, compare the specimens before and after aging according to GB/T 250, and the specimens after aging have slight discoloration. The discoloration grade is 4-5 grades (discoloration grade: 1 grade sample is completely discolored; 5 grade sample is completely unchanged).
The weather-resistant PP material is molded into a standard sample, and the tensile strength, elongation at break, notched impact strength, and color difference before and after aging are tested according to the relevant ASTM standards, and the discoloration of the appearance is graded.
The test conditions of the xenon Test Chamber are as follows
340nm irradiance 0.50W/m2, black mark temperature 65°C, relative humidity 65%, continuous light, water spray cycle 18h/102min (water spray time/no water spray time), test time 2000h.
The aging of materials in a xenon Test Chamber is a common test method to simulate direct sunlight or exposure to sunlight through window glass. We can select the characteristics of products or materials of interest in actual use for testing. We provide reliable test data for the research, development, use, supply and demand of plastic materials.
