Strengthening via Strain Hardening
The increase in hardness and tensile strength of a metal by mechanical deformation at room temperature, which hinders dislocation motion.
Physical-Chemical Mechanism of Action
In cold hardening, metals are deformed under mechanical stress (e.g., pressure or tension) at normal ambient temperature. This deformation hinders the dislocation motion of atoms and the crystal structure, resulting in increased hardness.
Metallurgical Relevance & Risks in Welding
Cold hardening can lead to overstress or excessive deformation if not properly configured, causing cracks and fractures in the material. It is important to ensure the correct load and deformation ratio.
Workshop Practice & Action Instructions
Use cold hardening for metals with low dislocation movement. The load should not exceed 10% of the elastic modulus. For high-carbon steels (e.g., HSS), careful control of deformation is necessary to avoid cracks.