Phase Transformation Effect on Residual Stress and Distortion — Lesson 4

This lesson covers the intricate process of phase transformation in welding, focusing on the Elasto plastic model and Thermo mechanical model. It delves into the residual stress analysis, the influence of microstructural changes, and the impact of phase transformation on the welding process. The lesson also discusses the generation of residual stress in a welded structure and how it can be calculated using a finite element based Thermo mechanical analysis. It further explores the role of temperature distribution, microstructural changes, and phase transformation in influencing the mechanical properties of a welded structure. The lesson concludes by explaining how to incorporate the effect of phase transformation in stress analysis models.

Video Highlights

01:22 - Consideration of the heating stage and solidification process in welding
05:50 - Phase transformation in low carbon steel and its influence on residual stress
14:42 - Influence of boundary conditions on residual stress generation
33:58 - Importance of heat source model in stress analysis

Key Takeaways

- Phase transformation plays a crucial role in the welding process, influencing the residual stress analysis and microstructural changes.
- Residual stress in a welded structure can be calculated using a finite element based Thermo mechanical analysis.
- Temperature distribution, microstructural changes, and phase transformation significantly influence the mechanical properties of a welded structure.
- The incorporation of phase transformation effects in stress analysis models can enhance the accuracy of calculations.
- The cooling rate in the welding process is linked to the microstructure of the welded structure, making it an essential parameter in the phase transformation process.