Due to their high damage tolerance, austenitic steels are promising candidates for additive manufacturing (AM) processes. It is well-known that defects such as pores, lack of fusion or residual stresses are induced by the process itself. However, due to characteristic cooling conditions in laser powder bed fusion, those austenitic alloys are often suffering from columnar grains and pronounced texture leading to highly anisotropic mechanical properties. This drawback can be addressed by an adapted solidification behavior imposed by an adequate alloying concept tailored for AM processes.
The present study reports on the processing of CrMnNi steels with different nickel contents by laser powder bed fusion. The as-built materials exhibit not only different elementary deformation mechanisms, i.e., twinning and martensitic transformation, under quasi-static mechanical testing, but also can be microstructurally tailored exploiting the characteristic intrinsic heat treatment due to different phase stabilities and constitution. By an adequate choice of alloying composition, tailored mechanical properties can be achieved and process-inherent residual stresses can be effectively reduced without any subsequent treatment.