Application of laser particle size analyzer in barium titanate particle size detection(2)

 1. Particle size detection of barium titanate

The crystal structure and properties of barium titanate are closely related to the grain size. As the grain size decreases, its crystal structure, ferroelectricity, and phase transition temperature all exhibit some novel properties that are different from coarse-grained materials. With research on nanometer barium titanate ceramic sensitive components. Especially temperature coefficient thermistors (PTC), multilayer ceramic capacitors (MLCCS). Thermoelectric elements, piezoelectric ceramics, sonar, infrared radiation detection, crystalline ceramic capacitors, electro-optical display panels, memory materials, polymer-based composite materials and layers etc.

It is well known that barium titanate particles, which are perovskite-type compounds with high dielectric constants, are widely used in multilayer capacitors. As a high dielectric material, tetragonal barium titanate is used in electronic components such as ceramic capacitors, positive thermistors, and high-frequency oscillators. There is a strong demand for barium titanate particles used in multilayer capacitors, which have no aggregation, good dispersibility and high crystallinity. For example, when making multilayer capacitors with small temperature dependence, barium titanate must be suppressed. Grain growth of raw material powder. In particular, in order to obtain a high-capacity capacitor, the raw material powder of barium titanate must be in the tetragonal crystal form.

In addition, in order to make the raw material powder into particles with excellent dispersibility, the shape of the barium titanate particles should be spherical, preferably as close to a perfect sphere as possible. On the other hand, in recent years, barium titanate has been used as one of the materials forming the internal electrode layers of multilayer capacitors.

2. Application of laser particle size analyzer in barium titanate particle size detection

     This test used the Winner802 nanoparticle size analyzer, with a test range of 1-10000nm. The particle size of the test sample barium titanate is small, about a few hundred nanometers. .The sample has fine particles and a large specific surface area, and agglomeration between particles is easy to occur. The barium titanate must be fully dispersed before testing. First put a small amount of sample into a beaker, add 3-5 drops of 50% sodium hexametaphosphate solution, and after fully soaking the sample, add 20ml of water, ultrasonic for 2, 5, and 10 minutes respectively, and then transfer 5mL of sample to the sample cell. carry out testing. 3. There is little change in the results of 5 minutes of ultrasound and 10 minutes of ultrasound. By comparison, the test data of adding 3-5 drops of sodium hexametaphosphate for 5 minutes of ultrasound is stable and reliable. The test concentration should not be too high. Generally, a photon number of 20-30 is better. The test data is stable, and the repeatability error and standard deviation are small.