Exam Question

(a) ### Types of Corrosion
**1. Stress Corrosion Cracking (SCC):**
This is a type of localized corrosion that results in the brittle failure of a normally ductile material when subjected to a combination of three specific factors: a susceptible material, a specific corrosive environment, and a sustained tensile stress. The stress can be applied externally or be a residual stress from manufacturing processes like welding or cold working. The corrosion attacks localized paths, such as grain boundaries, leading to the propagation of fine cracks that can cause sudden, catastrophic failure with very little overall loss of material.
- **Example:** Austenitic stainless steel in chloride-rich environments (like seawater) or brass in ammonia-containing atmospheres.