What role does cooling play after printing a layer in FDM?

Cooling after printing a layer in FDM is crucial for maintaining layer adhesion, which is key to the structural integrity of the printed object. As each layer is deposited, the material is still in a semi-molten state. Proper cooling allows the layer to solidify correctly and bond effectively with the layer above it. This bond provides strength and durability to the entire print, ensuring that the layers adhere to one another seamlessly.

While cooling can also influence dimensional accuracy when the material shrinks evenly, the primary reason why cooling is essential right after printing a layer is to foster good inter-layer adhesion. If the layers do not bond well due to inadequate cooling or too rapid cooling, it can lead to delamination or weakness in the print. Therefore, the process of controlled cooling is critical for achieving the desired mechanical properties and performance of the final product.