This standard is issued under the fixed designation D ; the 1 This practice is under the jurisdiction of ASTM Committee D01 on Paint and. ASTM D Testing Water Resistance in % RH. Can be used to test the water resistance of coatings by exposing coated specimens to a high relative. ACCELERATED LIFE TESTING. Touchstone performs corrosion testing and accelerated life testing of virtually any material or device. Among the tests offered .
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Another option is to continue the test until all specimens have failed, and use the time to reach failure as a way to differentiate performance. Short interruptions to inspect or remove specimens are permitted, but such interruptions should occur no more than once each day.
The minimum distance between adjacent test specimens shall be mm. Circulating fans should be used with caution d224 their use may reduce the temperature differential and limit condensation. Operate the test continuously with the test chamber closed unless otherwise speci?
Alternative practices for testing the water resistance of coatings include Practices DDand D The use of control specimens with known performance can also be used to determine the duration of the test that is required to produce meaningful results. Before using the exposure device to this standard for the? As the warmer saturated air passes the cooler specimens, water is deposited onto the specimens in the form asm condensation.
The values given in parentheses are for information only.
Any effects such atm color change, blistering, loss of adhesion, softening, or embrittlement are observed and reported. Some tests x2247 used for a pass or fail determination at an arbitrary time.
A coating system is considered to pass if there is no evidence of water-related failure after a period of time. This practice differs from other methods where condensation is only formed on the front coating surface, while the back surface is outside the exposure area.
Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. Reverify the chamber if there are any changes to the setup of the equipment or if any of the components listed in Section 5 are repaired or replaced. Other tests may also deposit water droplets on f2247 surface but where the source is not from condensation for example, water spray.
Water Resistance and Humidity (ASTM D 870, ASTM D 2247)
Users of this practice alone may use the known performance of the controls to set test end points. A coating system is considered to pass if there is no evidence of water-related failure after a period of time. This is a requirement in order for this procedure to work correctly. Remove only as many specimens as can be rated within the speci? Water permeates the coating at rates that are dependent upon the characteristics of the coating.
Rate specimens for changes in color, blistering, etc. Polyvinyl chloride pipe and? This astj this practice suitable for flat panels as well as large or 3D objects. It does not specify specimen preparation, or evaluation of results. This practice differs from other methods where condensation is only formed on the front coating surface, but the back surface is outside the exposure area. Another option is to continue the zstm until all specimens have aztm, and use the time to reach failure as a way to differentiate performance.
Such control specimens can provide warning of changes in test severity in a given apparatus, and can indicate variations in test severity between different apparatuses. Other tests are used to monitor degree of failure as a function of exposure time. Summary of Practice 3. This practice is therefore useful for evaluating coatings alone or complete coating systems. The saturated mixture of water vapor and air temperature rises and then cools below the dew point, causing condensation on the specimens.
The post-recovery rating allows evaluation of the permanent effects of the exposure as distinct from the transient effects, and is especially important for evaluation of color and gloss. This saturates the air 2d247 the lower portion of the test chamber with x2247 vapor.
It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
If condensation is not observed on any specimen immediately after the chamber is opened, discontinue the test and determine the cause of the lack of condensation before continuing.
As the warmer saturated air passes the cooler specimens, water is deposited onto the specimens in the form of condensation. After the specimens have been in an unopened chamber for at least 12 h, open the chamber and check for the presence of uniform condensation on each specimen.
Corrosion tests can zstm conducted, 2d247 the condensate dripping off the test articles in not recirculated. Approved December 1, The values d247 in parentheses are for information only. Primary limit control for immersion heater 6 5—Heated water tank for supplying heat and humidity to room 6—Immersion heater 7—Water temperature limit control 8—Constant level water tank unheated with over? Evaluate specimens no less than 5 min and no more than 10 min after removal from test, as the effects from water exposure can change within a 2d247 time.
Practices D cover application techniques for the production of uniform? It does not specify specimen preparation, or evaluation of results.