Finite element analysis of the powder metallurgy process for manufacturing LED ceramic sub-mounts

In the powder metallurgy process, if the compact body has a non-uniform density distribution, it would be very difficult to achieve the desired dimensional accuracy because of the non-uniform shrinkage that occurs during the sintering process. In the case of the ceramic sub-mounts of a light-emitting diode (LED), produced from a porous ceramic powder tape, the fabrication involves punch-forming, warm isostatic pressing, and sintering. To ensure the proper functioning of the reflective surface of the LED package, the surface should be produced with the designed angle. In this study, the shape deformation of the final product was predicted using a numerical simulation. A simulation model that can describe the deformation of a porous body based on the plasticity theory. The model considers both the compaction and sintering that occurs during the continuous fabrication process, and was used in a finite element analysis for designing the fabrication process. The angle of the reflective surface of the sub-mount was calculated for various punch angles, and the reliability of the simulation model was verified by comparing its predictions with experimental results.