Plastic Strain Amplitude
The plastic strain amplitude is the maximum plastic deformation a material withstands during a load cycle. It affects life under cyclic loading.
Physical-Chemical Mechanism of Action
Plastic strain amplitude describes the maximum plastic deformation a material can withstand during a load cycle. Each cycle deforms the material and returns it to its original shape, causing microscopic damage to the material.
Metallurgical Relevance & Risks in Welding
High plastic strain amplitude can lead to micro-deformation states that contaminate the material over time and reduce its service life. This can particularly lead to crack formation in highly stressed components such as aircraft parts or machine shafts.
Workshop Practice & Action Guidelines
To minimize plastic strain amplitude and increase material service life, the following measures should be taken during welding:
• Use an optimal welding process variant with low stress.
• Ensure proper pre-treatment of the material before welding (e.g., by tempering).
• Monitor material stress and, if necessary, perform service life predictions.