Fatigue in materials is caused by many factors. Pick - out the FALSE one from the following.

Explanation:

Fatigue strength:

• The fatigue strength of materials is highly sensitive to various internal and external factors. External factors include the part’s shape, size, surface finish, and service conditions, while internal factors include the material’s composition, microstructure, purity, and residual stress.
• A small change in these factors can cause fluctuations or significant changes in the material’s fatigue performance. Understanding the impact of various factors on fatigue strength is crucial in fatigue research.
• This research provides a foundation for the proper structural design of parts, the appropriate selection of materials, and the effective implementation of cold and hot processing technologies, ensuring that parts have high fatigue performance.

8 Factors Affecting Fatigue Strength Of Metal Materials:

1. Effect of stress concentration
2. The influence of size factor
3. Influence of surface processing state
4. The impact of loading experience
5. Influence of chemical composition
6. Effect of heat treatment on Microstructure
7. Influence of inclusions
8. Influence of surface property change and residual stress