Cellular Growth
Cellular growth is a solidification form where dome-shaped crystallites form parallel to the heat flow. It occurs at low alloy contents and high temperature gradients.
Physical-Chemical Mechanism of Action
Cellular growth is a special form of solidification growth where crystallites form in pointed-arch structures. These crystallites grow parallel to the heat flow and form a cellular structure. This process occurs when the alloying content is low and the temperature gradient is high.
Metallurgical Relevance & Welding Risks
Cellular growth can lead to a fine crystal structure, which increases the hardness of the material. However, it can also cause cracks and distortion if the material is not cooled properly. Too rapid cooling can cause the crystallites to be too closely packed, leading to cracking.
Workshop Practice & Action Guidelines
To control cellular growth, it is important to minimize the temperature gradient during welding. This can be achieved by careful selection of welding parameters and the use of cooling aids. The cooling rate should be set so that the material cools slowly and evenly to avoid cracking.