Internal stresses

In electroplating, internal stresses can occur during the coating process. These stresses are caused by structural changes in the coating material during the deposition process. Some of the main causes of internal stresses in electroplated coatings are

1. crystalline structure: during the deposition process, the metal ions on the surface of the substrate organize themselves into a crystalline structure. Different growth conditions can lead to an uneven distribution of the crystals, which can result in internal stresses.

2. different growth rates: Inhomogeneous growth rates of the coating material on the surface can lead to different stresses in different areas of the coating. This can be caused by factors such as local temperature differences or variations in the chemical composition of the electrolyte.

3. lattice defects and deformations: Lattice defects or deformations within the crystalline structure of the electroplated layer can lead to stresses. These defects are often caused by interactions between the metal ions and the substrate molecules during the coating process.

4. thermal effects: Temperature fluctuations during the coating process can lead to thermal stresses, especially if the coating material has a different coefficient of thermal expansion compared to the substrate.

Controlling and minimizing internal stresses in electroplated coatings is important to ensure adhesion, durability and mechanical integrity of the coatings. This can be achieved through optimized process control, the use of suitable coating materials and the application of post-treatment processes such as heat treatment.