Traditional synthesisSynthesis processesProcess such as the solid-state reaction method can be improved with additional procedures such as high-energy mechanical activationEnergy mechanical activation, improving precursor elements’ physical propertiesProperties like particle sizeParticle size. This work analyzes the microstructural propertiesProperties of the precursor elements by SEMScanning Electron Microscopy (SEM) with an activation processProcess. Solid solutionsSolid solutions are created by the solid-state reaction method with high-energy mechanical activationEnergy mechanical activation in a horizontal roller mill, subsequently the solid solutionsSolid solutions were sintered at 1200 °C for 4 h with a step of 4 °C per minute with x = 0.0, 0.001, 0.003, and 0.005, Ba1−2xEuxTi1−xO3 was used, and the type of atomic substitution at sites A and/or B in the ABO3 formula of barium titanate was analyzed. A tetragonal phase of barium titanate corresponding to JCPDS 96-150-7757 is determined by XRDX-Ray Diffraction (XRD), and the structural parameters a, b, c; volume; and crystal size are calculated by Rietveld refinement. No secondary phases are present.