Fig. 1 Schematic diagram of cutting a tensile sample from a sample prepared by SLM

Fig. 2 Microstructures of SLM-produced copper-bearing 316L SS: a SLM0Cu, b SLM3.0Cu, c SLM4.5Cu, d SLM6.0Cu (subscript 1, 2 and 3 represent without heat treatment, 500 °C heat treatment and 700 °C heat treatment)

Fig. 3 Average grain size statistics of SLM-produced samples

Fig. 4 XRD patterns of SLM-produced copper-bearing 316L stainless steel before and after heat treatment: a SLM0Cu, b SLM3.0Cu, c SLM4.5Cu, d SLM6.0Cu

Fig. 5 Strength a and elongation b of SLM-produced copper-bearing 316L stainless steel before and after heat treatment

Fig. 6 Summary of ultimate tensile strength and elongation for copper-bearing 316L SS [35]

Fig. 7 Fracture morphologies of SLM4.5Cu: a without heat treatment, b 500 °C heat treatment, c 700 °C heat treatment (subscript 2 is an enlarged picture of subscript 1)

Fig. 8 TEM images of SLM4.5Cu after the tensile test: a without heat treatment sample, b 500 °C heat treatment sample, c 700 °C heat treatment sample, and d copper-rich precipitation in a 700 °C heat-treated sample

Fig. 9 TEM images of SLM4.5Cu tensile deformation samples after 700 °C heat treatment: a the cellular structure, b the ε-Cu nanoparticle sheared by dislocation, c schematic diagram of the interaction between twins and dislocations, d TEM images highlighting some stacking faults along the slip directions

Fig. 10 Schematic illustration of the relationship between deformation substructures, deformation mechanisms, and stress-strain curves in copper-bearing 316L stainless steel during plastic deformation before and after heat treatment