POROUS TITANIUM IMPLANTS FABRICATED BY A SALT BATH SINTERING PROCESS FOR BONE REPAIR APPLICATIONS

摘要

A salt bath sintering method was developed for fabricating porous titanium constructs that potentially could be used as implants in bone repair. Advantages of the method include low-cost fabrication, control of the porosity and pore size, and ease of fabricating anatomically relevant shapes. Mixtures of titanium and sodium chloride (salt) particles were compacted to form a cylindrical shape, and sintered for 2 hours in a salt bath at 1200 °C. After dissolution of the salt, porous titanium constructs with controllable porosity in the range 36 to 65% and pore sizes of ~30 μm to ~200 μm were obtained. The compressive strength and elastic modulus of the cylindrical constructs decreased from 216 to 36 MPa and from 9.8 to 1.8 GPa, respectively, with an increase in the porosity from 36 to 65%, and showed an exponential dependence on the porosity. The porous constructs supported the proliferation of murine MLO-A5 cells (an osteogenic cell line), showing their cytocompatibility. Prototypes of a porous Ti insert that could be used to augment the fixation of femoral and tibial stems in total joint arthroplasty were produced to show the applicability of the process.