Dissemination of IT for the Promotion of Materials Science (DoITPoMS)


Dendritic Growth

The animation below shows how the temperature gradient in the liquid affects the morphology of the growth front in a pure metal:

The animation referred to the driving force for solidification, which is greater for larger undercoolings. To see why, click here.

When a dendritic structure forms, the dendrite arms grow parallel to the favourable growth directions, normally 〈 100 〉 in cubic metals. Grains which are orientated with the 〈 100 〉 direction close to the direction of heat flow will grow fastest and stifle the growth of other grains, leading to a columnar microstructure. To see more about how a microstructure develops in a casting, see the microstructure of a cast ingot section of the TLP on Casting.

Micrograph no 617 in library This micrograph (left) is an image of the 3D structure of dendrites in a cobalt-samarium-copper alloy, taken with a scanning electron microscope .
This micrograph (right), taken with a reflected light microscope, shows the appearance of dendrites of a copper-tin alloy when observed as a 2D section through the 3D structure. IMage do micrograph 485 in the library