Further studies on the plasma-sprayed amorphous phase in hydroxyapatite coatings and its deamorphization.
Plasma-sprayed hydroxyapatite coatings contain a quite large amount of amorphous phase. Infrared analysis shows that the plasma-sprayed amorphous phase is an oxyapatite and the coating predetermined as a hydroxyapatite is proved to be an oxyhydroxyapatite with a small quantity of hydroxyapatite. Heat treatment promotes the transformation of amorphous oxyapatite into a crystalline hydroxyapatite structure and reduces the dissolution rate of the coatings. Further studies focus on the properties of the amorphous phase, showing that amorphous oxyapatite is more soluble in 0.15 M lactic acid at 25 degrees C and that water molecules can accelerate the amorphous/crystalline transformation of the hydroxyapatite structure during the plasma-spraying process.
Institute of Materials Science and Technology, Sichuan University, Chengdu, People's Republic of China.
J
J
Weng
X
X
Liu
X
X
Zhang
Z
Z
Ma
X
X
Ji
Z
Z
Zyman
D003460:Crystallization; D017886:Durapatite / Q000737:chemistry*; D006361:Heating; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000737:chemistry; D019344:Lactic Acid; D008422:Materials Testing; D011208:Powders; D019736:Prostheses and Implants; D013055:Spectrophotometry, Infrared; D014867:Water / Q000737:chemistry
D007773:Lactates; D011208:Powders; D014867:Water; D019344:Lactic Acid; D017886:Durapatite