Research on Abnormal Grain Growth in the Conventional Sintering of (K0.5Na0.5)NbO3 Nano Powders

Abstract

Abstract About 30nm grain sized (K0.5Na0.5) NbO3 powders were used as the raw materials, and the solid phase method was used to prepare potassium sodium niobate ceramics at 750~ 950°C under normal pressure sintering. The abnormal grain growth (AGG) at process of powder sintering was investigated. The consequences demonstrate that when the sintering temperature is greater than 850°C, AGG can be clearly observed. As the sintering temperature increases, the number of areas where abnormal grain growth occurs increases as well as the size. When the sintering temperature is 950°C, the area of abnormal grain growth has a maximum of approximately 1mm × 1mm, and it has good (111) orientation. The difference in the sintering driving force caused by the size distribution in the potassium sodium niobate nano powder is the root cause of abnormal grain growth.