Quantitative characterization of pores in transparent ceramics by coupling electron microscopy and confocal laser scanning microscopy

This work is dedicated to the implementation of a new characterization method of porosity in transparent ceramics. This quantitative method couples scanning electron microscopy with confocal laser scanning microscopy. From this original method, the volume fraction of pores has been determined for different sintered Nd:YAG specimens with an accuracy of about 10%. This technique appears to be promising because it leads to both the pore size distribution and the residual porosity for fully dense samples. For example, it becomes possible to reach porosity levels ranging from 0.09% to 0.0004% for transparent Nd:YAG specimens which could not be measured by using conventional techniques. Finally, correlations between the residual porosity of these full dense samples and their optical properties could be established.