What is Additive Manufacturing?

Additive Manufacturing (AM), also known as 3D printing, is the process of manufacturing components through the addition of material in a series of layers melted or fused together to create the part. This process allows complex parts to be built as a single component and can deliver additional benefits that conventional manufactured parts could not.

There are 7 distinct AM techniques:

Material Jetting
Powder Bed Fusion
Material Extrusion
Vat Photopolymerisation
Sheet Lamination
Direct Energy Deposition
Binder Jetting


All systems use Computer Aided Design (CAD) models of the component which can range from low to high geometric complexity. The layer-by-layer AM processes allow designers and manufacturers to challenge conventional designs. With added design freedom parts can be developed to have further advantages, delivering benefits throughout the supply chains of many different industry sectors.

Contributing towards Industry 4.0, the 4th industrial revolution, some AM processes allow small batches of components to be built within the same build. These parts can be identical of completely unique to each other. The processes also cuts down on production time, compared to most conventional methods, whilst requiring less tooling to complete each part. For these reasons AM is not only favoured for final industrial parts but also rapid prototyping, design development and tooling.


Croft Additive Manufacturing Ltd specialise in Selective Laser Melting, a Powder Bed Fusion process that constructs components through layering metal powder, fusing the powder within each layer according to the CAD file. The process uses a metallic powder, in Croft’s case this is Stainless Steel 316L. The powder is spread evenly across a build plate, the laser then melts the powder according to the CAD data. The build plate then drops 50 micron and another powder layer is added. The laser then melts this layer to the previous layer. The process is repeated until the final part is complete. This process differs to subtractive methods, using the required material to build the part and any excess powder that has not been used is recycled back into the machine’s powder delivery system.