Copper precipitation mechanism
Copper precipitation is the process where copper drops out of the solid solution and remains as submicroscopic particles. This increases the hardness and tensile strength of the material.
Physical-Chemical Mechanism of Action
Copper precipitation occurs when the solid solution is supersaturated with copper. During thermal aging (cooling), the copper precipitates and forms submicroscopic clusters or particles. This changes the material's microstructure.
Metallurgical Relevance & Welding Risks
Copper precipitation can lead to increased hardness and tensile strength, making the material harder and reducing its formability. This can cause stress buildup and possible cracking in the weld pool. Additionally, it can cause difficulties in melting and deforming the material.
Workshop Practice & Action Instructions
To minimize copper precipitation, the material should be thoroughly melted before welding. Cooling steps should be controlled and slow to ensure uniform deformation. For high copper contents, it may be helpful to reduce the copper content before welding or use alternative materials with lower copper content.