Simultaneous quantitative analysis of structural and mechanical properties in Sn-doped BaTiO₃ ceramics using a...

A multimodal Laser Opto-Ultrasonic Dual Detection (LOUD) technique is presented in this work for the comprehensive characterization of BaTiO₃ ceramics doped with varying Sn concentrations. The main objective was to evaluate these materials' quantitative elemental composition, grain size, and porosity simultaneously, thus overcoming the constraints of conventional approaches that necessitate separate instruments and procedures. The synthesis of Sn-doped BaTiO₃ ceramics was carried out using a solid-state reaction method, with nominal Sn doping concentrations ranging from 0 % to 20 %. The findings revealed a mean grain size of 8.88 μm and a standard deviation of ±3.80, alongside a mean porosity of 11.43 % with a standard deviation of ±2.30, regardless of doping concentrations. The findings indicated that higher Sn concentration resulted in a notable decrease in grain size from 14.39 μm in pure BaTiO₃ to 4.08 μm in BaTiO₃ doped with 20 % Sn, accompanied by a corresponding increase in porosity from 9.25 % to 13.66 %. The samples were evaluated quantitatively using the LOUD technique, combining laser-induced breakdown spectroscopy (LIBS) and laser ultrasonics (LU) to assess their compositional, structural, and mechanical characteristics. Optical signal processing in the LOUD technique enabled accurate quantitative compositional analysis via the calibration-free LIBS technique, revealing precise concentrations of Ba, Ti, and Sn, with a proportional increase in Sn content relative to the doping levels. Meanwhile, ultrasonic signal processing enables accurate grain size and porosity determination by LU parameters (attenuation coefficient and velocities). The correlation analysis of the LU parameters in evaluating grain size (R² = 0.989) and porosity (R² = 0.995) demonstrated good reliability compared to the results obtained from traditional electron microscopy and Micromeritics testing. This study validates the LOUD technique's effectiveness in providing a thorough, simultaneous analysis and reinforces its potential as a valuable tool for advancing materials science research.