Ti6Al4V foams fabricated by spark plasma sintering with post-heat treatment

Ti6Al4V foams were fabricated by the spark plasma sintering (SPS) with post-heat treatment using a blend of Ti6Al4V and sodium chloride powders. The microstructure and properties of the foams were investigated by scanning electron microscopy, X-ray micro-CT, Synchrotron X-ray, compression test and cell experiments. Results showed that the Ti6Al4V foams fabricated at 700 °C and 50 MPa in the SPS cannot get high relative densities. These sintered foams were post-heat treated in a pressureless mode of the SPS at 1100 °C for 5 min. This heat treatment is very effective to reduce the microporosity and to densify the foam walls. Youngʹs modulus of the foams was in the range of 33.0–9.5 GPa and yield strength ranged from 110.2 MPa to 43.0 MPa with porosity values from 44.7% to 70.0% obeying the Gibson–Ashby models. The human osteoblast cell line MG-63 validated the cellular acceptance of the foam surfaces. The pressureless SPS provides a new method for the heat treatment of metallic foams.