: Specimens are exposed on all sides, often supported by wire mesh to prevent warping.
: This practice specifically covers materials exposed directly to the environment, unlike ASTM G24 , which focuses on exposure behind glass.
: Specimens are attached to a solid substrate, like plywood, which can increase surface temperature and simulate certain end-use conditions. astm g7 pdf
: Specimens are mounted on a black-painted aluminum box to simulate the higher temperatures experienced by materials like automotive coatings.
: It is not intended for the corrosion testing of bare metals (refer to ASTM G50 for those procedures). : Specimens are exposed on all sides, often
Predicting how a material will degrade over several years is complex due to year-to-year climatological variations.
: To ensure data reliability, the standard strongly recommends using at least one control material with known durability for performance comparison. Why the ASTM G7 Standard Matters : Specimens are mounted on a black-painted aluminum
: ASTM G7 allows for three primary mounting styles:
: The standard accounts for critical environmental stressors including ultraviolet (UV) radiation , temperature fluctuations, moisture (rain/dew), and pollutants. Key Testing Procedures in ASTM G7