Interfacial Fracture Toughness of a Plasma Sprayed Hydroxyapatite Coating Used for Orthopedic Implants
This study introduces a new method for evaluating the adhesion strength of a coating on a substrate. The interfacial fracture toughness, Γ i is used to assess the work per unit area required to separate an interface. Γ i is measured for the as-received specimens of hydroxyapatite plasma sprayed on Ti-6A1-4V substrate. Calculation of the interfacial fracture toughness requires that the elastic modulus of the coating to be known. The Young's modulus of the plasma sprayed hydroxyapatite is assessed using a bend test. The effect of aqueous environment on the interfacial fracture toughness is also investigated.
According to Mazhai Oil Field's hostile sandstone reservoir factors,we introduce HD surfactant.Laboratory tests indicate that the HD surfactant suit high salt and high temperature oil floor,and can improve effectually oil quality.6 well times of injection well Permeability control jobs were completed,the cumulative increased oil was 2937t.Thus HD surfactant suit Mazhai Oil Field.So HD is a good oil displacement agent.