The method of preparing porous tantalum medical implant material is to send the mixed tantalum powder after mixing pure tantalum powder and forming agent into the printing platform of 3D printer for rolling and laying layer, and the printing head of 3D printer will spray binder to bond the mixed tantalum powder to form a two-dimensional plane, and the workbench will drop 80 ~ 100μm for processing the next layer, stacking and forming layer by layer. The unbonded tantalum powder particles were removed to obtain the preliminary sample, and then the porous tantalum medical implant material was prepared by post-treatment including degreasing, vacuum sintering and cooling. The volume ratio of the pure tantalum powder to the molding agent is 60 ~ 80:20 ~ 40, and the binder is α-cyanoacrylate with a mass concentration of 1%. The porous tantalum medical implant material obtained by the preparation method of the invention has complete three-dimensional porosity connectivity, good biocompatibility, and the mechanical properties are consistent with the load-bearing bone tissue of the human body.
Refractory metal tantalum, due to its excellent biocompatibility and mechanical properties, its porous material is expected to replace the above-mentioned traditional medical metal biomaterials and become a biomaterial mainly used as bone tissue necrosis treatment. Due to the harmless, non-toxic and no side effects of tantalum metal on the human body, and with the rapid development of medical science at home and abroad, the further deepening of the knowledge of tantalum as a human body implant material, people's demand for porous tantalum metal materials for the human body has become more and more urgent, and the requirements for it are becoming higher and higher. Tantalum, as a porous medical metal, is an important connection component material to ensure the normal growth of new bone tissue if it has a high uniform distribution of connected pores and physical and mechanical properties suitable for the human body.
At present, the preparation methods of porous tantalum biomaterials mainly include powder loose sintering method, foam impregnation sintering method, slurry foaming method, etc. All these methods require the application of molds. The biggest feature of biomaterials is that the shape is complex and the requirements for small details are high. Therefore, high requirements are put forward for the molding technology, but the traditional molding technology cannot meet the requirements due to the limitation of the mold.
