About

Additive Manufacturing (AM), also called 3D printing, refers to a group of production techniques in which parts are made from 3D model data by joining materials layer by layer (see figure left). AM offers many advantages compared to subtractive manufacturing (SM), chiefly its almost unlimited design freedom, enabling unprecedented levels of functional integration, and the capability to produce personalised parts locally with efficient material use. This has evoked a true revolution in manufacturing, and rapid growth of the AM sector, representing a unique opportunity for the strongly-needed return of the manufacturing industry to Europe. To achieve this AM must overcome a number of challenges. AM is a young technology, most contemporary Computer Aided Engineering (CAE) tools do not support the freedom of design that AM allows, and traditional design practices, having evolved alongside conventional subtractive manufacturing, are often predicated on the high level of geometric and material certainty that has come from >100 years of research into SM. In recent years there have been dramatic improvements in AM design methods, process control, post-processing, material properties and material range. However, if AM is going to gain a significant market share it must be developed into a true precision manufacturing method. The production of precision parts relies on three principles:

1. Production is robust, i.e. that all sensitive parameters can be controlled.
2. Production is predictable, e.g. the shrinkage that occurs is acceptable because it can be predicted and compensated in the design.
3. Parts are measurable, as without metrology accuracy, repeatability, and quality assurance cannot be known.

AM of metals is an inherently a high energy process, with dozens of sensitive and inter-related process parameters, making it susceptible to thermal distortions, defects and process drift. The modelling of these processes is beyond current computational power and novel methods are needed to practicably predict performance and inform design. In addition metal AM produces highly textured surfaces and complex surface features that stretch the limits of contemporary metrology. With so many factors to consider, there is a significant shortage of qualified, trained and expert personnel. Shortage in skills is an important barrier for a wider uptake of advanced manufacturing technologies in Europe and action is thus needed.