ASTM B920 is the standard practice for evaluating porosity in gold and palladium alloy coatings on metal substrates by vapors of sodium hypochlorite solution. It is used to help identify coating discontinuities that may affect appearance, protection, or service performance. For buyers, labs, and quality teams, this ASTM standard supports more consistent inspection of plated finishes and helps provide a common technical basis for comparing coated parts.

ASTM B920 standard overview

ASTM B920 addresses a specific way to assess porosity in gold and palladium alloy coatings applied to metal substrates. The standard focuses on using vapors of sodium hypochlorite solution as the test medium, which makes it relevant to surface quality evaluation for these noble-metal alloy finishes. In practice, ASTM B920 helps define a repeatable approach for checking whether a coating contains pores or discontinuities that could influence performance or cosmetic acceptance.

Where is ASTM B920 used?

This standard is commonly used in quality control and testing environments where gold and palladium alloy coatings are applied to metal parts. It is relevant to plated components that need reliable surface integrity and consistent finish assessment. ASTM B920 may be used by manufacturers, plating operations, laboratories, and procurement teams that need a recognized method for evaluating porosity before parts are released, accepted, or compared against technical requirements.

Practical importance of ASTM B920

ASTM B920 matters because porosity can affect whether a coated surface meets expected quality levels. Using a recognized standard practice helps reduce variation in inspection and supports clearer communication between suppliers and customers. It can also aid product evaluation, incoming inspection, and compliance workflows by providing a common reference for test method selection and reporting. For coated metal substrates, that consistency is especially valuable when finish quality is part of acceptance criteria.

• Porosity evaluation for gold and palladium alloy coatings
• Vapor-based sodium hypochlorite test approach
• Surface integrity and discontinuity checking
• Quality control for coated metal substrates
• Comparable results for acceptance and procurement