Influence of hot isostatic pressing on sintering trajectory and optical properties of transparent Nd:YAG ceramics

Abstract : Controlling residual amounts of defects in transparent ceramics is a major challenge for laser applications. This study was focused on the influence of post-sintering treatment by hot isostatic pressing (HIP) on microstructural evolution during reaction–sintering of Nd:YAG ceramics. This work shows that the pores–grain boundary separation phenomenon can be avoided thanks to suitable post-HIP treatment. As a result, this study shows that fully dense and highly transparent Nd:YAG ceramics with microsized grain can be manufactured by HIP technology. Finally, laser oscillation was demonstrated and laser slope efficiency appears to be enhanced with HIP treatment.