1.Introduction to Barium Titanate Ceramics

Barium titanate (BaTiO₃) is a classic ferroelectric compound in the BaO-TiO₂ system. It is a typical perovskite-type crystal with good dielectric and ferroelectric properties. It is the basic base material for electronic ceramic components and is widely used in the production of small-volume, large-capacity micro-capacitors and temperature compensation components. It is also used to make nonlinear components, dielectric amplifiers, electronic computer memory components, ceramic sensitive components, microwave ceramics and piezoelectric ceramics, multilayer ceramic capacitors, thermistors, electro-optical devices and dynamic random access memory. It is the basic raw material for electronic functional ceramic devices, so it is called "the pillar of the electronic ceramic industry" by many scholars and manufacturers.

2.Crystal structure of barium titanate ceramics

As important raw materials for ironmaking and sintering, the demand for limestone and dolomite will further increase with the development of the steel and cement industries. SiO₂, CaO, MgO, Al₂O₃, and Fe₂O₃ are important indicators for judging the quality of limestone and dolomite. It is particularly important to quickly and accurately analyze the content of these components. At present, chemical methods are usually used for testing, which is cumbersome to operate and has a long analysis cycle. XRF has the characteristics of multi-element analysis, simple operation, and high sensitivity. This experiment uses the tablet pressing method, which is simple and fast, with a solid sample and simple and fast determination, to explore the accuracy of XRF in limestone and dolomite testing and evaluate whether it can meet the needs of limestone and dolomite industrial production.

The crystal cell structure of barium titanate (a) is cubic phase, (b) and (c) are tetragonal phases

3. Application of XRD in the detection of barium titanate ceramic materials

Tetragonal barium titanate has good dielectric, piezoelectric and ferroelectric properties and is widely used in multilayer ceramic capacitors (MLCC), thermistors, dynamic memory and optoelectronic devices. Compared with cubic type, tetragonal barium titanate has spontaneous polarization phenomenon, and its ferroelectric, piezoelectric and thermoelectric properties are better. The application of XRD in barium titanate ceramic materials is mainly phase analysis, such as studying the crystal transformation of barium titanate ceramic materials at different calcination temperatures. Specific unit cell parameters can also be obtained according to Rietveld refinement (full spectrum fitting), and the composition of the crystal phase can be further judged by referring to the axial ratio c/a value.

4.Application Case

The FRINGE CLASS benchtop X-ray diffractometer was used to perform phase analysis on two groups of barium titanate powder samples provided by the customer.

（1）Picture of sample to be tested

Left: Sample BaTiO₃-1; right: Sample BaTiO₃-2

（2）Test Result Display 

XRD Spectrum of BaTiO₃-1

XRD Spectrum of BaTiO₃-2

（3）Conclusion

As can be seen from the picture, the phase of the BaTiO₃-1 sample is cubic barium titanate (PDF#00-031-0174); the phase of the BaTiO₃-2 sample is tetragonal barium titanate (PDF#04-009-3215), which has a double peak structure of (200) and (002) at about 2θ 45°,that means the diffraction peak is split. When there is only one diffraction peak, it is a complete cubic phase. When there are two diffraction peaks, it means that there is a tetragonal phase, and the degree of splitting becomes more obvious with the increase of the tetragonal phase content.