THERMOLUMINESCENCE OF BONE EQUIVALENT CALCIUM-PHOSPHATE CERAMICS

TL-glow curves of calcium phosphate ceramic powders prepared either fr om natural or synthetic phosphates have been investigated. The TL-samp les from synthetic phosphates, particularly those having Ca/P ratio 2. 8, show higher TL-sensitivity, about 1/10 times that of LiF TLD-100 po wders, with glow curves having maxima (peaks) around 110, 175 and 325 degrees C. The TL-response of all phosphate ceramic samples showed a d ependence on gamma-dose, well described by a power function in a range from about 1 to 10(4) Gy, which is useful for therapeutic and radiati on processing levels. For regeneration of irradiated TL-samples, annea ling around 350 degrees C for 20 min was found suitable. A low Ca/P ra tio can be recommended for high dose measurements, while higher ratio gives greater TL-sensitivity, hence allowing measurement of lower gamm a-doses.