المعنى والاستخدام
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)
نصف القطر
1.1 This practice covers the fundamentals and operating procedures for ultraviolet (الأشعة فوق البنفسجية) 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. إعداد عينة, strength, شروط الاختبار, and evaluation of results are described in other ASTM test methods or specifications.
1.3 يجب معاملة القيم المعبر عنها بوحدات النظام الدولي للوحدات كقيم قياسية. لم يتم تضمين أي وحدات قياس أخرى في هذه المواصفة القياسية.
1.4 لا يهدف هذا المعيار إلى معالجة جميع المخاوف المتعلقة بالسلامة, لو اي, المرتبطة باستخدامه. تقع على عاتق مستخدمي هذا المعيار مسؤولية إنشاء السلامة المناسبة, الممارسات الصحية والبيئية وتحديد مدى انطباق القيود التنظيمية قبل الاستخدام.
1.5 يعتمد هذا المعيار الدولي على مبادئ التقييس المعترف بها دوليًا المنصوص عليها في القرار المتعلق بمبادئ تطوير المعايير الدولية, المبادئ التوجيهية والتوصيات الصادرة عن لجنة منظمة التجارة العالمية المعنية بالحواجز الفنية أمام التجارة.