Inverse Identification of the Post-Necking Behavior of Metal Samples Produced with Additive Manufacturing

Abstract

Additive manufacturing (AM) is undoubtedly the fastest-growing technology in the field of component productions. In particular, metal AM is rapidly emerging thanks to its enormous potentiality in manufacturing components with complex shapes and high structural performances. Although the precision and the rapidity of the production process is continuously improving, the performance of the final components in terms of crashworthiness and mechanical properties is still under evaluation. In this work, several specimens were manufactured using metal AM, in particular the Selective Laser Melting (SLM) method was employed. The used material is steel. All specimens have the same dimensions, but they were created using different paths of the laser source with respect to the metal powder layers during the AM process. Afterwards, the specimens were subjected to tensile test and the deformation field was measured using Digital image Correlation. The post-necking behavior as well as the anisotropy were evaluated using the Virtual Fields Method. It turned out that the laser paths used during the forming process have an impact on the plastic flow at large deformation up to the final fracture. The variance of the mechanical properties and the experimental uncertainties are discussed thoroughly.