In the AWS stainless steel classification, what does the 308 indicate?

• A. Mechanical properties
• B. Chemical composition
• C. Heat treatment
• D. Corrosion resistance

Answer: (B)

The digits in the AWS stainless steel designation are all about the alloy’s chemistry. The 308 tag points to a specific chromium–nickel stainless composition, meaning this designation identifies the particular mix of elements used in that filler metal. It’s about what elements and their amounts are in the alloy, not about how strong it is, what heat treatment it needs, or how resistant it is to corrosion in every situation. The reason this matters is that the filler metal’s chemistry is chosen to weld well with common austenitic stainless steels (like 304/304L) and to produce a weld with compatible properties. So the 308 designation indicates chemical composition, rather than mechanical properties, heat treatment, or corrosion resistance.