Evaluation of energy absorption performance and Johnson-Cook parameters of lattice-structured steel parts manufactured via SLM

In this study, a hybrid manufacturing approach was applied to iron-based materials, combining SLM processing with additional sintering heat treatment. During manufacturing, metal powders were enclosed within a closed volume along with lattice support structures fabricated by SLM. The enclosed powders were subsequently sintered, forming a porous inner region integrated with the outer SLM-processed shell. This novel approach aims to enhance energy absorption and mechanical performance. Hybrid specimens were subjected to impact and split-Hopkinson bar tests at various velocities. The Johnson-Cook material parameters were determined based on energy absorption, displacement, and other mechanical properties. Results demonstrated the superior energy absorption capability of the manufactured parts, with samples achieving an absorbed energy of 250 J at an impact velocity of 9 m/s. This study highlights the potential of integrating SLM with sintering techniques to create hybrid materials with optimized structural and mechanical performance, offering valuable insights for applications requiring high energy absorption and strength.