Effect of Plasma Spraying Power on Shear Strength of Hydroxyapatite Coated on Carbon/Carbon Composites

Hydroxyapatite (HA) was coated on C/C composites by a plasma spraying method.The shear strength between HA coatings and C/C substrates at different plasma spraying powers was examined.The micrographs of HA coatings,cross interface and shear fracture surfaces were detected by scanning electron microscopy.The failure mechanism of shear fracture was studied also.The shear strength at plasma spraying power of 40 kW was the highest,which was about 10 MPa.The shear failure occurred mostly within HA coating.