3. Controls required in AF

3.1 Raw material

Raw material controls mainly concern powders. However, control of carbon black content and ash content for liquids, phase change temperatures for filaments, flatness, roughness and waviness for foils may also be required.

• In order to guarantee good repeatability and reproducibility of the manufacturing process, and to obtain parts of good quality (predictable and reproducible), the characteristics of the powders must meet certain criteria which need to be assessed by means of controls. Ultimately, the results of these checks will provide the correlation between the characteristics of the powder and the material being manufactured. In fact, the characteristics of the material will depend not only on the machine parameters,...