The use of additive manufacturing processes is increasing within industrial applications, as they bring some significant customer benefits compared to conventional processes. Additive manufacturing is based upon the layered structure of a component. The production time therefore depends on the volume to be applied to the component. The geometric shape of the individual layers has a minor influence. This results in a greater amount of design freedom, without incurring extra time and cost through additional steps, such as machining. This process is particularly suitable for the production of geometrically complex components, such as bionic structures. The process from the CAD file to the finished component is largely automated. In this way, initial models of components can be produced quickly and cost-effectively. These and many other advantages have led to the fact that additive manufacturing has established itself in many industrial applications. In particular, powder-based (such as selective laser sintering) and melting processes (such as fused layer modelling) are used, for example, for the production of prototypes, and also for standard components.
In contrast, additive manufacturing processes are based on the extrusion of liquids. This area is still in its infancy, but is currently developing fast. In particular, the large number of new materials for 3D printing creates great application potential for this technology. These include, for example, silicone (see Fig. 1), resins or metal pastes.
This whitepaper looks at existing technologies for the additive manufacturing of components from liquid materials. The advantages and disadvantages of the individual processes are presented, as well as the different control parameters for each process for changing the quantity applied.
Methods for additive production with liquids and pastes:
- Pneumatic dosing unit
- Drop-On-Demand (Jet-Valve)
- Endless piston principle