Bioconductivity and mechanical properties of plasma-sprayed dicalcium silicate/zirconia composite coating

摘要

Dicalcium silicate (C_2S)/yttria stabilized zirconia (YSZ) composite coatings possessing better durability and more superior mechanical properties than pure C_2S coatings were produced by atmospheric plasma spraying. The microstructure and phase composition of the composite coatings were determined by scanning electron microscopy and X-ray diffraction. The bioconductivity of the coatings was evaluated in vitro by incubating in simulated body fluids (SBF). Apatite was observed to precipitate even on coatings comprising more than 70% YSZ after immersion in SBF for 7 days. The changes of the mechanical properties of the composite coatings due to immersion in SBF were also investigated. The durability was found to increase with a larger YSZ content in the coatings. Deterioration of the mechanical properties can be attributed to the degraded interlamellar or cohesive bonding due to fast dissolution of C_2S. This study reveals factors affecting the durability of the C_2S/YSZ composite coatings in simulated physiological environment and suggests means for improvement to address clinical needs.