Mechanical properties and machinability of GYGAG:Ce ceramic scintillators

Abstract

Cerium doped gadolinium yttrium gallium aluminum garnet ceramics, GYGAG:Ce for short, have drawn a lot of attention and showed a very promising application in medical CT detectors. This mainly attributes to their excellent scintillation properties, such as high light output, low afterglow, fast decay and high x-ray stopping power. In order to provide more accurate lesion location in real CT diagnosis, ceramic scintillators need to be machined into regular pixelated arrays, and the pixels should well match with the photodiode elements. Therefore, in addition to the scintillation characteristics, the mechanical properties and machinability of these ceramic scintillators should have been studied further, but such data and references are limited. In this research, we focused on the mechanical properties and the machinability behaviour of GYGAG:Ce ceramics. It was observed that GYGAG:Ce ceramics with grain size around 8 μm have the highest mechanical strength, and are highly suitable for machining process to achieve fine array pixels, for which a strict dimensional tolerance needs to be held.