Transcrystalline SCC occurs in which stainless steel grade?

• A. Martensitic
• B. Ferritic
• C. Austenitic
• D. Precipitation Hardened

Answer: (C)

Transcrystalline cracking means the crack travels through the grain interiors rather than along grain boundaries. This crack path is most characteristic of austenitic stainless steels, which have a face-centered cubic structure. Under tensile stress in chloride-containing environments, these alloys are prone to cracking that advances through grains due to the combination of anodic dissolution and hydrogen-assisted mechanisms within the grain, producing transgranular cracks. Ferritic and martensitic stainless steels, when susceptible, tend to show cracking behavior that involves grain boundaries more readily, and precipitation-hardened grades don’t define transgranular SCC in the same way. So the stainless steel grade associated with transcrystalline (transgranular) SCC is the austenitic type.