Definition - What does Dendrite mean?
A dendrite is a characteristic of a metal or alloy that makes them weak and imperfect. This defect occurs when a hot metal alloy is cooled instantly or too quickly for diffusion to take place. This causes the alloy to enter a non-equilibrium condition because the alloy's exterior cools and suddenly solidifies, whereas the inside remains hot and soft. When this occurs, a treelike structure (a dendrite) forms between the internal molecules of the alloy.
Corrosionpedia explains Dendrite
Dendritic growth has huge consequences for the material's properties. Alloys must be maintained at equilibrium temperature conditions during their manufacturing to give them the proper strength and durability.
Non-equilibrium temperature conditions can lead to coring and dendrite formation in the internal molecules of a metal alloy, thus leading to the metal's failure and corrosion to the metal structure. Coring in alloys results in the retention of more of the higher melting temperature element at the center of the grains in an alloy. In this case, the dendrite arms formed from the exterior have a different composition than the alloy in the inner regions, resulting in a local compositional difference that reduces the alloy's quality and performance.