Influence Of Nano-Alumina On Properties Of Alumina Ceramics

Alumina Ceramics

Alumina ceramics are structural ceramic materials with a-Al2O3 as the main crystal phase. Due to its high melting point, high hardness, heat resistance, corrosion resistance, electrical insulation and other characteristics, it can be used in harsher conditions. Alumina ceramics are cheap and mature in production technology. It is currently one of the largest and most widely used ceramic materials. Mainly used in knives, wear parts, bio-ceramics and other fields. In addition, it is widely used in energy, aerospace, chemical, chemical and electronic fields.

However, due to the low toughness and brittleness of ordinary alumina ceramics, its application fields are limited. In addition, the higher sintering temperature is also the main reason for its limited application. In order to obtain ceramic materials with higher hardness and crystallinity, sintering must be carried out at higher sintering temperatures, which inevitably leads to an increase in energy consumption.

In recent years, due to the higher and higher requirements for material properties, various methods have been proposed to improve the properties of alumina ceramics, including hot pressing sintering, spark plasma sintering, microwave sintering, and adding additives. After taking some new measures, the performance of alumina ceramics in terms of flexural strength and hardness has been greatly improved.

Nano Alumina

Since the last century, nanotechnology has developed vigorously, and various nanomaterials have been continuously developed. The progress of nanotechnology has had a profound impact on the alumina industry, bringing new research directions for the wide application of nano-alumina. As a special functional material, nano-alumina has many excellent properties such as high hardness, high strength, corrosion resistance, wear resistance, high temperature resistance, high insulation, high oxidation resistance, etc. It is widely used in precision ceramics, bioceramics, chemical catalysts, refractory Materials, Integrated Circuits and Aerospace.
Nano-alumina and alumina are the same substance, but with different strengths. So, what is the effect of adding a certain amount of nano-alumina into alumina ceramics?

• A certain amount of nano-alumina is added during the preparation of alumina ceramics. During the molding process, the nano powder can be fully filled into the voids of the alumina powder, reducing pores, increasing the strength of the molded body, and facilitating sintering.
• Due to the small size and high surface activity of nano-alumina, adding a certain amount of nano-alumina can effectively increase the diffusion rate on the surface of the blank, reduce the sintering temperature, and improve the degree of densification after sintering. product.
• This is because the nano-alumina has a large number of interfaces, which provides a short-range diffusion path and a higher diffusion rate, so that the sintering driving force of the material also increases sharply, which greatly speeds up the entire sintering process and greatly reduces the sintering temperature.
• While reducing the sintering temperature of alumina ceramics, the crystallinity will not decrease. The so-called crystallinity is the degree to which the material crystallizes with a certain atomic arrangement law during the sintering process, that is, the percentage of the mass or volume of the crystalline part to the total mass or volume, in other words, the ratio of the crystalline area of ​​the product after sintering.

With different crystallinity, the physical and mechanical properties of materials are also different, and the electrical and optical properties of materials are also affected by crystallinity to a considerable extent.

• Improve the hardness of alumina ceramics.
• Improve the strength of alumina ceramics.
• Increase the elastic modulus of alumina ceramics and improve toughness.

In comparison, the physical properties of pure nano-alumina ceramics are much better than ordinary alumina ceramics, but the preparation process of nano-alumina ceramics is complicated and the cost is high. In addition, the alumina ceramic itself has very excellent properties. In some cases, some nano-alumina can be selectively added to improve performance, which not only ensures product quality, improves production efficiency, but also reduces production costs. The alumina ceramics produced by Pintejin Ceramics are processed with high concentration alumina ceramics in standard proportions to obtain various ceramic parts, such as ceramic tubes, ceramic plates, ceramic rings, etc.

About China Advanced Ceramic CNC Machining Company – Be-Cu

Manufacturer of precision machined components. Ceramic cnc machining components include high dielectric strength, electrical & corrosion resistance, & non-porous & non-shrinking properties.Manufacturer of high temperature fabricated and machinable ceramics including alumina, glass-ceramic, alumino-silicate, boron nitride and zirconium phosphate. Adhesives, coatings and potting compounds to 3200 degrees F,Air firing services for ceramics up to 1650 degrees C also available. Products include insulators, guides, washers, tubes, blocks, & rods for thermal, electrical, corrosion exposure, structural, wear, & semi-conductor operations. Services include machining to tolerances of +/- .0001, ultrasonic core drilling, centerless grinding, milling, & ID & OD threading.Surface grinding, dicing, OD (outer dia.) grinding, ID (inner dia.) grinding, centerless grinding, hole drilling, jig grinding, lapping, honing & polishing service are also available. Diamond grinding with dimensional tolerances of 5 microns & surface finishes of 0.2 microns (8 micro-in.) can be performed.Blanket orders and AutoCAD files & other 3d files accepted.Contact us for your machining ceramic project!