**Figure 26.**

*Quantitative result values.*

stress, survival probability and surface roughness were considered [8]. As a result,

The residual stresses and assessment methods mentioned in the above studies can often be different from the residual stresses in welding and their more complicated assessment methods. This is because, in the case of welding, the change of the metal structure due to the introduction of heat energy occurs, and thus a complicated residual stress is formed. However, the residual stress generated in this study is not related to the residual stress due to the temperature change and is related to

quantitative fatigue safety factor as shown in **Figure 26** was obtained.

*New Challenges in Residual Stress Measurements and Evaluation*

**Figure 25.**

**Figure 26.**

**140**

*Quantitative result values.*

*Method for durability assessment.*

the shrinkage and relaxation of the existing material. Therefore, it is possible to perform a definite durability assessment only by the basic relationship between the basic load and the material (**Figures 27** and **28**) [10].

**Figure 27.** *Phase diagram of Fe-Fe3C.*

**Figure 28.** *Continuous cooling transformation diagram.*
