Technical ceramic balls
Ceramic balls can be used for grinding, attrition or mixing of powders. Their more or less spherical shape ensures efficient grinding. Precision balls with a perfectly spherical shape can be used in other areas as metrological gauges or mechanical parts. We offer balls in various sizes (from 1 mm to 100 mm diameter) to better suit our customers' needs. These balls are generally made of alumina or zirconia which, thanks to their properties, allow the balls to be used in severe environments: wear, corrosion, low contamination rate of the grinding media.
What are the different types of beads we offer?
There are two main families of ceramic balls: grinding balls and precision balls. For both categories of balls, we offer products made of Kyocera alumina (DEGUSSIT AL23 or F99.7 which contain 99.7% pure alumina) as well as Kyocera yttriated zirconia 3Y-TZP.
The grinding balls are very effective for attrition or mixing of powders and other products. Their shape does not have to be perfectly spherical since grinding or mixing a product does not require perfect geometries. Therefore, they often have cylindrical shapes with hemispherical ends.
The shape of precision balls is much more precise, reaching the perfect sphere. They are polished at the end of their machining to perfect their sphericity. The fields of application are much more specialized, such as high precision ball bearings, non-return valves. Thanks to their internal microstructure, their shape, their density and their mechanical properties, the precision of the tasks carried out with these balls can reach the micron.
The dimensions of these balls are variable: the diameter of the rounded base of a grinding ball is identical to its height and varies between 5 mm and 30 mm (with possible diameters ranging from 5 to 5 mm). The diameters of precision balls vary between 1 mm and 100 mm.
Why choose alumina or zirconia balls?
Our balls are made of alumina or zirconia, which gives them a high density: the density of alumina is almost 4 g/cm3, that of zirconia is about 5.8 g/cm3. Apart from the aspect of density and hardness, alumina and zirconia are technical ceramics with important thermal and mechanical properties.
Indeed, zirconium oxide resists thermal shocks and temperatures that can exceed 1000 °C. Aluminum oxide is resistant to even higher temperatures (up to 1950°C for Kyocera DEGUSSIT AL23 alumina, which is 99.7% pure). Thus, alumina balls are fully suitable for high-temperature applications. Both industrial ceramics also exhibit excellent wear, abrasion and corrosion resistance, making them durable over time and suitable for use with the vast majority of products. This ensures that grinding balls will be usable with almost any product without having to worry about its corrosiveness and that precision balls will have a long operational life, despite the friction they will be subjected to.
What are ceramic balls used for?
Ceramic grinding balls are used for powder attrition. They are placed in containers with the powder to be ground. Once the containers are set in motion, the balls move and allow the powder in question to be considerably refined by friction. This process can last several hours in order to obtain the finest possible result. The choice of products to be ground is quite wide since alumina and zirconia are resistant to high temperatures, corrosion and abrasion. This can range from clays to much more corrosive products. In addition, it is recommended to use fairly dense balls (such as zirconia balls) for grinding abrasive or hard raw materials such as silicon carbide or metals.
Grinding balls can also be used to make mixtures. The concept is the same as for attrition: the balls are placed in a container with several products that you want to mix efficiently. The beads will move in the container and will eventually, by rolling, allow to obtain a homogeneous mixture.
Moreover, the precision balls can be used as a template. Indeed, the dimensional stability of the ceramics used ensures that the dimensions of the ball will not change and that it will remain perfectly spherical regardless of the conditions. They can also be used in very specific applications such as high precision and high speed ball bearings, non-return valves to control the direction of flow of fluids in piping systems, or even in the automotive or medical fields.