Stress Corrosion Cracking (SCC)
Stress corrosion cracking is caused by tensile stresses and corrosive media, leading to cracks. This can damage components.
Physical-Chemical Mechanism
Tensile stresses can cause microscopic cracks or stress cracks in metals. Corrosive media like water, salts, or chemical liquids exploit and widen these cracks. Corrosive substances react with the metal, dissolving ions, which leads to further cracking.
Metallurgical Relevance & Welding Risks
Stress corrosion cracking can occur in newly welded parts, especially if the weld isn't fully relieved or tensile stresses develop. This leads to cracks and distortion, shortening part life and compromising safety.
Shop Practice & Action Items
To avoid stress corrosion cracking, make sure welded areas are fully stress-relieved. Use correct welding parameters and cool parts slowly. In humid or chemically aggressive environments, do regular corrosion checks and apply corrosion protection if needed.