Substrates must undergo mechanical finishing, cleaning, and chemical pretreatments to ensure coating quality.
The standard provides seven distinct types of coatings (A-G), primarily differentiated by their . Description Key Characteristic Type A Thickest option, typically 50 µm min. unless specified. Type B Architectural Class I Designed for maximum durability and outdoor exposure. Type C Architectural Class II General purpose for external or internal use. Type D Automotive Exterior High resistance to road salts and environmental stress. Type E Interior / Decorative Focus on appearance and moderate protection. Type F Interior / Decorative Thinner decorative layer for mild environments. Type G Chromic Acid Type astm b580-79 pdf
The 1979 version contained a notoriously strict phosphoric acid immersion test for sealing quality. Many anodizers found it too aggressive compared to the later ASTM B136 (modified dye stain test). If your contract cites B580-79, you are forced to run this dated, harsh test. unless specified
Standard Specification for Anodic Oxide Coatings on Aluminum Type D Automotive Exterior High resistance to road