SUOYI Zirconia Toughened Alumina Powder ZTA Powder ZTA Ceramics

SUOYI Zirconia Toughened Alumina Powder (ZTA) Powder, ZTA Ceramics

Zirconia toughened alumina powder,Compared to single-phase Al₂O₃ and monoclinic ZrO₂ ceramics, ZTA ceramics possess superior mechanical properties, showing broader application prospects in high-end industrial fields such as biomedicine, electronics, semiconductors, and functional ceramics.

Zirconia toughened alumina ceramics, abbreviated as ZTA ceramics, have high hardness, high melting point, and resistance to acid and alkali corrosion, while also possessing strong toughness, making them suitable for various applications in high-temperature structural ceramics.

1. When the zirconium oxide content is 10%~20%, it can inhibit the acidity of aluminum crystal growth, thus increasing the material's hardness.

2. When the zirconium oxide content is 12%~15%, the hardness and strength of ZTA ceramics reach their maximum values.

3. When the zirconium oxide content is 20% and it is in a highly dispersed state, the mechanical properties of ZTA ceramics will reach their best state after hot pressing and sintering.

In the preparation of ZrO2/Al2O3 composite powder, the core process involves multiple steps such as green body forming and sintering. To improve the performance of zirconia-toughened alumina ceramics, the quality of the ZrO2/Al2O3 composite powder must be guaranteed first. hydrothermal synthesis.

1. Continuous Method: Zirconia and alumina raw materials are mixed in a specific ratio and reacted directly in a reactor at room temperature and pressure to generate nanoparticles. The alumina completely coats the zirconia particles. After filtration, drying, and Calcination at 880℃, a homogeneous ZrO2/Al2O3 composite powder is obtained.

2. Mechanical Mixing Method: The mechanical mixing method involves mixing and ball-milling the powders composed of monoclinic alumina and monoclinic zirconia, followed by sintering. The mechanical mixing method for preparing ZrO2/Al2O3 composite powder requires mixing and ball milling of the powder raw materials, followed by sintering. This method is direct and simple, but it cannot guarantee the uniform dispersion of multiphase components.

3. Coprecipitation Method A typical coprecipitation method involves preparing a mixed solution of aqueous solutions of ZrOCl2, 8H2O, and AlCl3, 6H2O. This solution is then atomized and added to dilute ammonia water (pH=9) at a constant temperature of 40℃, with rapid stirring to produce coprecipitate. The precipitate is then filtered, dried, ground, and calcined at 840℃ to obtain a homogeneous ZrO2/Al2O3 composite powder.

4. Sol-Gel Method The sol-gel method for preparing ZrO2/Al2O3 composite powder requires first uniformly mixing inorganic or organic zirconium (aluminum) salts in a solution, followed by hydrolysis and polymerization to generate a sol system. The sol is transparent and, after aging and polymerization, forms a gel. Drying and calcining the gel yields ZrO2/Al2O3 nanocomposite powder. This preparation method improves the dispersion of ZrO2 within Al2O3.

5. Hydrothermal Synthesis Method The hydrothermal synthesis method uses a well-sealed pressure vessel (requiring significant investment). An aqueous solution is placed inside as the reaction medium, and the vessel is heated to dissolve substances that are insoluble or sparingly soluble under normal conditions, followed by recrystallization. ZrO2/Al2O3 composite powder can be prepared using this method.

Regardless of the method used, it is essential to ensure both small ZrO2 particle size and a narrow particle size distribution, as well as uniform dispersion of ZrO2, so that the Al2O3 particles can completely encapsulate ZrO2 to produce a good toughening effect.