**Preface to "Additive Manufacturing (AM) of Metallic Alloys"**

Developed in the 1980s, additive manufacturing (AM), known as rapid prototyping, has already revolutionized the production of polymeric material components. New developments in AM technologies are providing industries with the ability to build structural components with a variety of metal alloys, ceramics and composite materials. The introduction of metal AM processes has revolutionized the production of metallic components in the industrial sectors, where complex geometries, organic shapes, tubular, hollow designs, and dense, lattice-filled structures play a decisive role. In AM, there is no correlation between complexity and cost. Sometimes, more complexity means lower costs: less material and no need for assembly. However, there are problems that limit the wider uptake and exploitation of metals in AM. These range from the lack of design and modeling skills and AM software, to the different properties that are obtained using the same technology but different machines, to the difficulty of perfectly simulating the processes, to the incomplete understanding of the causes of variation in the quality of the parts, and to the repeatability of the processes.

> **Flaviana Calignano** *Editor*

## *Editorial* **Additive Manufacturing (AM) of Metallic Alloys**
