Here, SEM images of fracture surfaces and the density changes of green compact are used to evaluate the strength of granules. The observation point for SEM was the center of the compact under different CIP pressures of 10–100 MPa. In Fig. 7, a carcass of spherical shape remained until 60 MPa, but a homogeneous surface structure was completely formed under 80 MPa. The densities of green compacts showed a gradual increase in Fig.