Formation and Growth Mechanism for Layered and Tunnel Potassium Titanate Whiskers in Calcination Synthesis

摘要

A way based on the image method was proposed to study the microstructure development and formation process for potassium titanate whiskers. The microstructure and morphology comparisons were done between the sinters and their remains after dissolving the non-crystalline hydrosoluble products for different reaction stages. It was found that the layered K_2O4TiO_2 whiskers were formed form the K_2O2TiO-2 crystal firstly and the tunnel K_2O6TiO-2 whiskers evolved from the K-2O4TiO_2 whiskers in the later phase transition reaction. The K_2O-rich liquid phase melting from the K_2O2TiO-2 crystals splits them into the K-2O4TiO_2 whisker and wraps the K-2O4TiO-2 whiskers into sheafs after it condensing. The K_2O-rich liquid phase melting from K-2O4TiO_2 whiskers makes the diameter of the generated K-2O6TiO_2 whiskers decrease. The effect of oriented disssolution and split for K_2O-rich liquid phase results in the whisker's formation and growth.