Magnetic Particle Inspection Level 1 Practice Exam

What type of discontinuity is stress corrosion cracking classified as?

1. Aging

2. Fabrication

3. Inservice

4. Manufacturing

The correct answer is: Inservice

Stress corrosion cracking is classified as an inservice discontinuity because it occurs during the operational lifespan of a material or component, influenced by the combination of stress and a corrosive environment. This type of discontinuity is critical to understand as it can develop over time under specific conditions while the component is in use, making it a major concern for the integrity and reliability of structures and components exposed to corrosive elements. The other classifications, while relevant in different contexts, refer to distinct stages or processes in the lifecycle of materials. Aging discontinuities pertain to changes that occur as materials are subjected to environmental factors over time but do not necessarily involve an active service condition. Fabrication discontinuities are issues that arise during the manufacturing phase of a component, such as defects introduced through welding or machining. Manufacturing discontinuities generally occur at the initial stage of production or in the assembly process, while inservice discontinuities develop when a component is already operational. Understanding the nature of stress corrosion cracking as an inservice issue is vital for maintenance and monitoring strategies to prevent failures.