Spark plasma sintering of macroporous calcium phosphate scaffolds from nanocrystalline powders

Spark plasma sintering (SPS) technique was applied to fabricate macroporous β-tricalcium phosphate (β-TCP) scaffolds from nanocrystalline powders (termed “nano-scaffolds”) for bone regeneration applications. The degree of porosity (55–70%) and the macropore size (300–500 μm) of the scaffolds were controlled by modulating the porogen additions. Microstructures with ultrafine grain size (200 nm), increased density of solid matrix, and enhanced neck growth, as well as improved compressive strength and elastic modulus of over 50–100% were achieved in the macroporous nano-scaffolds by SPS in a modified graphite die. The SPS may provide an alternative approach to fabricate macroporous bioceramics nano-scaffolds.