Significato e uso
4.1 This practice is used to determine the effects of ultraviolet light or ultraviolet light and water on adhesive bonded joints under controlled but artificial conditions. The results of this practice can be used to compare the relative durability of several adhesives under specific laboratory UV exposure.
4.2 This practice is not intended to determine the lifetime prediction of the adhesive in use. It is only used to determine the relative durability between different adhesives.
4.3 Due to the different spectral irradiance of the lamp, the results obtained may vary depending on the light source (xenon arc or fluorescent ultraviolet). Adhesives should not be compared based on their performance under different types of light sources.
4.4 When operating conditions vary within the scope of a given method, the results obtained may vary. Results may also vary when exposing instruments made by different manufacturers. Materials can only be compared if they are tested simultaneously in the same instrument. Be sure to accurately report operating conditions.
4.5 The type of transparent adhesive used and the UV transmittance characteristics have a significant impact on the rate and type of degradation of the adhesive under test. Adhesives can only be compared when tested on the same type (recommended is the same batch) of transparent adhesives with the same UV transmittance.
4.6 This approach is not intended to determine the impact of atmospheric pollutants, biological organisms, salts or freeze-thaw cycles.
ASTM D904-2021 Fluorescent Ultraviolet (see Method A) or xenon Arc Sources (see Method B)
Raggio
1.1 This practice covers the fundamentals and operating procedures for ultraviolet (UV) aging (with or without water) of adhesive joints with at least one glass or transparent adhesive using fluorescent UV (see Method A) or xenon arc light sources (see Method B).
1.2 This practice is limited to equipment that acquires, measures and controls aging conditions, and exposure procedures. preparazione del campione, strength, test conditions, and evaluation of results are described in other ASTM test methods or specifications.
1.3 I valori espressi in unità SI sono trattati come valori standard. Nessun'altra unità di misura è inclusa in questo standard.
1.4 Questo standard non è destinato ad affrontare tutti i problemi di sicurezza, se presente, legati al suo utilizzo. È responsabilità degli utenti di questo standard stabilire una sicurezza adeguata, pratiche sanitarie e ambientali e per determinare l'applicabilità delle restrizioni normative prima dell'uso.
1.5 This international standard is based on internationally recognized standardization principles established in the Decision on Principles for the Development of International Standards, Linee guida e raccomandazioni emesse dal comitato dell'OMC sugli ostacoli tecnici al commercio.