In the automotive industry, they use the SAE J standard to evaluate weathering of exterior plastic materials by accelerated means. Most engineers involved. 22 Apr SAE J SAE J is the performance standard based on the test parameters of SAE J Use of xenon arc test apparatus to perform. SAE J is a guide for comparing the performance of test equipment. SAE J and J gave automotive manufacturers the opportunity to standardize .
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Know that SAE J standards were developed in the s and are still used for preliminary tests; but be aware that auto manufacturers dae real outdoor testing to validate lab results and to develop new auto-exterior materials.
According to Weiss Gallenkamp, manufacturer of xenon-arc devices, the type of cooling used in the device has a negligible effect on the light output, but does affect overall design. Since Planck’s law says that photon energy is inversely proportional to wavelength, this low wavelength UV has sufficient energy to cause much more damage to organic materials than sunlight.
To understand SAE J standards, you should know about the equipment used to complete the tests. Test equipment must also pass a verification process before it can be used in the lab. In other words, only certain approved tools can be used to perform the tests. Unlike the small amount of exterior material sample tested j1906 SAE J, even small impurities can alter the effects of UV radiation on the auto as a whole.
The SAE J test does include heat ageing 83C and water spray cycles so it should account for some of these other effects you mention.
How to Understand SAE J | It Still Runs
In short, the exterior of each finished automobile is unique, and is subject to unique weather conditions, meaning that SAE J is an effective guide, but not always an accurate saw of testing.
Automotive OEM’s require this. Materials degrade or exhibit changes like fading, loss of luster, change in tensile strength or corrosion because molecular bonds have been broken and chemical reactions have occurred within the material.
Xenon-arc equipment cannot exactly mimic the effects of true sunlight because absorption of UV radiation is absolutely wavelength-dependent. The automotive industry uses the SAE J standard j1690 evaluate how exterior plastics on automobiles weather. She writes about a variety of topics, from new technology to animal husbandry.
All information presented is for general reference and does not represent a professional opinion nor the policy of an author’s employer. SAE J sets the protocol for the operating procedures of a controlled irradiance, xenon-arc apparatus. While this sometimes results in faster same-type degradation hence the yr Miami “equivalent” it can both cause failures not seen in outdoor exposures as well as cause different kinds of changes some actually less severe!
Xenon and Carbon Arc Weathering Standards. Also, the wavelengths of UV radiation from sunlight varies at different times of the day and throughout the year.
SAE J1960: How does it correlate to Florida exposure
While you might think that this would just result in a shorter test time, it has frequently been shown that the SAE J test as written has the potential to change the photochemiisty of degradation. So when m1960 J to outdoors, you’re comparing apples to oranges and they don’t equate. Melissa Bajorek began eae professionally in Bajorek has an Associate of Arts in business management from the University of Phoenix and holds certifications in marketing and advertising.
Either way, it can be a non-predictive test for some materials. These tests assume the time-temperature superposition principle without taking into account thermooxidative effects at higher temperatures, or the deleterious effects of shorter wavelength light and thus higher energy.
SAE J How does it correlate to Florida exposure
Has there been any activity focused on changing the light source and filters to more accurately predict real life exposure? Photo Credits red car image by Tammy Mobley from Fotolia. Another issue with SAE J standards is that real auto-exterior materials are produced in a factory, where impurities and contaminants do exist.
SAE J sets the standards for test duration, which is length of exposure to the xenon-arc device, and states protocol for the proper preparation of material samples prior to testing. To understand SAE J standards, you must be aware of its inaccuracies, as the standards do not exactly represent real world weathering of materials. About the Author Melissa Bajorek began writing professionally in We see the same thing in tests like UL for wire and cable.
It’s not possible to diagnose a finishing problem or the hazards of an operation via these pages. Some polymers undergo heat degradation that cause yellowing or darkening not at all due to UV.
One other factor is that this type of comparison, based on a single factor solar radiant energy does not take into account the other weathering factors of heat, moisture, etc. To understand SAE J, you sa know the issuing committee and the purpose of the tests, as well as some details about what it covers and wae potential inaccuracies.
Any new xenon-arc test equipment must be verified by a contracted third party. First, it is important to understand that the spectral power distribution light 1j960 vs. When this test temperature is lowered to 63C, the effect of discoloration is much less pronounced and we can focus mostly on the UV effects. SAE J tests are performed in laboratories by auto manufacturers and parts suppliers.
Still, it’s a conundrum when considering accelerated tests like Xenon Arc or even oven aging, to test under more severe requirements to predict performance over very long periods of time i.
These h1960 can be caused by forces other than sunlight. This device is used to mimic UV radiation and outdoor conditions, to weather samples of auto exterior or interior plastics or fabrics. Ci Xenon Aae Finishing. To understand SAE J, note that in some regions automobile exteriors will weather differently due to outdoor conditions. There are two primary types of xenon-arc instruments: In the automotive industry, they use the SAE J standard to evaluate weathering of exterior plastic materials by accelerated means.
We use SAE J heavily for automotive and non-automotive weathering as a defacto test to predict long term performance.