Very true Tom Joad
Cooling down of an extremely heated (melted) metal creates stress and cristalisation within the metal.
The slower you cool it, the less stress.
With layered AM, the aggregation from liquid to solid is in one direction:
The builded part is very hot, and on the other side of the new builded layer, it is cold.
Theirefore the stress within the material is always in one direction.
So, the higher the temperature is outside the new builded layer, the less stress you build.
The less energy you put in every layer (small building rate with minimal power), the less stress you built.
And it is the same for grain growth, cooling down slowly, cooling down in the same speed in all directions means little or no grain growth.
So building in an environment that is heated close to the melting point of the builded material is the best way.
Cooling down of the builded part needs to be done very slowly, and be sure there is no cooling down in any direction.
Sciaky has no heated building chamber, uses a lot of power to built a layer.
Cooling down is in one direction, and very vast.
