To minimize the stress shielding effect of metallic biomaterials in mimicking bone, the bodycentered cubic (bcc) unit cell-based porous CoCrMo alloys with different, designed volume porosities
of 20, 40, 60, and 80% were produced via a selective laser melting (SLM) process. A heat treatment
process consisting of solution annealing and aging was applied to increase the volume fraction of
an -hexagonal close-packed (hcp) structure for better mechanical response and stability. In the
present study, we investigated the impact of different, designed volume porosities on the compressive
mechanical properties in as-built and heat-treated CoCrMo alloys. The elastic modulus and yield
strength in both conditions were dramatically decreased with increasing designed volume porosity.
The elastic modulus and yield strength of the CoCrMo alloys with a designed volume porosity of
80% exhibited the closest match to those of bone tissue. Different strengthening mechanisms were
quantified to determine their contributing roles to the measured yield strength in both conditions.
The experimental results of the relative elastic modulus and yield strength were compared to the
analytical and simulation modeling analyses. The Gibson–Ashby theoretical model was established
to predict the deformation behaviors of the lattice CoCrMo structures.