YSZ Balls

Yttria Stabilized Zirconia

Features of YSZ Grinding Media – Highly Engineered Performance
Development of high energy media mills (e.g., planetary, vibratory and stirred media mills) and rigorous requirements of continuous and contamination-free grinding and dispersion of high viscosity and high percentage solid formulations demand high performance milling media. The high density, high fracture toughness,Yttria stabilized zirconium oxide grinding media high hardness and wear resistance, high chemical resistance, high purity, wide size range, regular shape, narrow size distribution, smooth surface and low surface friction are the core factors in grinding media. 
Our yttria stabilized zirconia grinding bodies are produced from high purity super-fine raw materials, using precision forming techniques followed by carefully controlled, high temperature siYttria stabilized zirconia grinding mediantering and proper surface conditioning. During the production process the raw materials are continuously checked and the manufacturing is strictly controlled assuring the first quality of the product.  
Our YSZ grinding media are engineered to satisfy your most demanding needs. The unique combination of material composition, manufacturing and surface conditioning yields high performance ceramic grinding media with outstanding properties.
High density – intense impact, high shear, reduced grinding time and high throughput
  • Yttria stabilized zirconia is one of the densest ceramic available. Top quality Y-TZP has a density of ≥6.0 g/cm3, which is approximately 2.5 times that of glass aYttria stabilized zirconia grinding mediand 1.5 times that of alumina (aluminium oxide, Al2O3) and zircon (zirconium silicate, ZrSiO4). Due to this high density, YSZ grinding media may be used to mill even high viscosity compounds, in which other media may float.
  • In media mills, particles are ground by impact and shearing forces between the grinding bodies moving relatively to each other, and between the grinding media and the mill parts. Particle grinding is determined by two main parameters: the stress intensity (which is proportional to kinetic energy of grinding bodies) and the frequency of stresses (frequency of grinding media interactions or number of contact points). The stress intensity must be high enough to initiate the grinding process. The higher density of yttria-zirconia grinding bodies provides the greater kinetic energy needed by high viscosity and high percentage solid formulations.
  • Fine particle distribution requires a high number of contact points. YSZ's higher density allows smaller sized grinding bodies, resulting in more body per charge, and providing more contact points and narrower gaps between the bodies, so higher shear. (The smaller media bed act as a filter which creates finer and finer particles by allowing the smaller particles to pass through the void spaces more easily while it slows down the passage of the larger particles.) This results in greater grinding efficiency and reduced grinding time.
  • Yttria stabilized zirconia grinding media grind significantly faster than glass, alumina or zirconium silicate media. Thus, significantly higher productivity may be achieved.
  • An increase in media density increases the mill throughput at which hydraulic media packing occurs in continuously operating mills. Hydraulic packing occursYttria stabilized zirconia grinding media when drag forces on the media due to product flow force the beads to statically pack around the discharge screen, forming a non-flowable interlocked configuration. This phenomenon causes excessive mill and media wear and mill shutdown.
  • In case of continuously operating high energy mills, the efficient bead separation is based on centrifuging the media out of the slurry. Centrifuging force is a function of the mass multiplied by the square of the peripheral velocity at the end of the rotor. Consequently, for example, we can more than double the separation force by using an yttria stabilized zirconia grinding media instead of glass media. Among other reasons, this is why high density Y-TZP ceramic grinding beads are so suitable for high viscosity formulations. We need the mass of the bead to increase the centrifuging force to overcome the drag force of the product flow.
  • The high density of yttria stabilized zirconia media provides greater grinding efficiency, reduced processing time, higher throughput and the ability to process higher viscosity formulations.  
High fracture toughness – reduced breakage, less contamination and maintenance
  • The fracture toughness of Y-TZP ceramic is more than two times greater than that of alumina, which is on the highest level in the industry. This is due to the aforementioned transformation-toughening mechanism which resists crack propagation and enhances toughness. Yttrium oxide stabilized zirconium oxide grinding beads
  • High toughness makes yttria stabilized zirconia grinding bodies highly resistant to fracture from the frequent mechanical shock found in mills and attritors, so there is no contamination by the broken milling media in the material being ground.
  • The solid body composition eliminates hollow beads and surface satellites that can shatter during milling, causing clogging of strainers, damage of mill parts and screen-blinding problems.
  • The reduced breakage results in a longer mean time between failures (MTBF), which means less downtime and less maintenance costs
  • When using YSZ grinding media, mill efficiency significantly increases, while product contamination, mill wear and maintenance expenditure considerably decreases. High fracture toughness and wear resistance makes yttria-zirconia grinding media suitable for high energy milling processes.   


High hardness and wear resistance – insignificant contamination, long service life
  • Ultra low wear loss as a result of the transformation-toughening mechanism unique to Yttria stabilized zirconia grinding beadsthe Y2O3-ZrO2 material system. Wear rate substantially lower than glass, alumina, zirconium silicate and magnesia stabilized zirconia (MSZ, MgO-ZrO2) grinding media, and lower than ceria stabilized zirconia (CSZ, CeO2-ZrO2) media. Yttria stabilized zirconia has the best wear properties of all the grinding media, i.e., Y-TZP milling media have significantly longer service life than other media.
  • High hardness and excellent wear resistance enable to grind successfully even strongly abrasive products, such as ceramic powders and pastes (e.g., zirconia powders) without damaging the media and formulation pollution
  • Y-TZP grinding ball is isostatically pressed then sintered at high temperature to give a finished product. Isostatic pressing ensures that the density and hardness of the product is uniform which leads to extremely low and uniform wear rates.
  • Media wear rate and abrasiveness towards mill depends on the media size, namely, the finer the grinding media, the lower the media and mill wear. This means, that usiYttria stabilized zirconia grinding mediang finer YSZ media instead of a larger size low density media (the reasons see above), the media and mill wear decreases.
  • Since the wear rate is extremely low, YSZ grinding media help to achieve steadier operating conditions over longer production periods, consequently, consistent and reproducible formulations. This improves the quality of the formulations.
  • If the mill produces the same desired particle size over a longer period, quality control time cycles can be lenghtened. This leads to definite savings. Steadier working conditions (longer lasting media and mill parts) ensure consistent quality control with much less effort. (When the milling process is constantly changing due to the wearing of the media and mill components, quality control is on a moving target.) 
  • YSZ milling media enable grinding highly abrasive materials, improve the quality of mill output, minimize downtime with less frequent repairs, and reduce maintenance and quality control costs. Due to the superior wear resistance, YSZ media is the best choice for today's continuously operating high energy mills.
High chemical resistance – suitable for wet operations
  • Yttria stabilized zirconia is inert virtually to all acids, bases, solvents, and other corrosive fluids and slurries except hydrofluoric acid, so it is suitable for wet grinding. Using this media Yttria stabilized zirconia (Y-TZP) grinding mediain wet operations, there is no contamination caused by solved media material. They offer the advantages of the density of metallic media without corrosion and colouring problems.
  • Since the surfaces of the grinding bodies are extremely smooth and yttria stabilized zirconia has excellent resistance to thermal shock, Y-TZP grinding media are easily and quickly washable between formulations, allowing production programs to be switched quickly.
  • Yttrium oxide stabilized zirconium oxide grinding media provides optimum results when used in wet grinding and dispersing applications, including the processing of highly viscous materials. It is, for example, suitable particularly for dispersing and mixing of highly viscous automotive and industrial paints.


High purity – suitable for sensitive applications
  • Y-TZP is almost free from contamination of impurities such as Fe2O3, SiO2, Na2O, MgO and free from any kind of heavy metals.
  • Yttria stabilized zirconia grinding media are non-radioactive, non-conductive and non-magnetic. Yttria stabilized zirconia grinding beads
  • Since the material is pure, and its wear and chemical resistance is excellent, media induced product contamination is practically nil when YSZ grinding media are used, which leads to better quality mill output.
  • These grinding media are suitable for sensitive pharmaceutical, bio-technical, cosmetic and food industrial applications, for grinding of high purity ceramic powders for structural and electronic applications.


Wide range of types and sizes – for a wide range of application

  • Yttria stabilized zirconia milling media are available in various shapes and sizes for any kind of mills such as micro mill, ultra micro mill and vibratory mill, ball, sand, pearl, turbo, pin and attrition mill to grind and disperse various materials effectively and economically.
  • YSZ can be used in all types of mills which are suitable to work with high density grinding media, including traditional mills and the most high energy mills on the market.
  • The availability of very small diameter sizes makes yttria-zirconia grinding media cost effective for many appliYttria stabilized zirconia grinding beadscations, and makes it suitable for ultra fine grinding and dispersion, moreover, for nanoparticle production. Media milling is the best-established manufacturing method for nanoparticle production. Nanoparticles are required by ceramic, coating, ink, cosmetic, pharmaceutical, bio-technical, food and other industries. To anticipate new applications, mill manufacturers are continuously developing new separation systems allowing the use of finer and finer beads.
  • Micro beads, beads, balls, radius/chamfered end cylinders and radius dome end cylinders are also available in a wide size range, which means that there is appropriate YSZ grinding media for the widest range of application including ultra fine grinding and dispersion, and nanoparticle production.


Uniform size – high efficiency milling, narrow formulation particle size distribution
  • Thanks to the advanced production processes, we can offer all types of yttria-zirconia grinding bodies with narrow size distribution.
  • The precise sizing guarantees good fluidity of the slurry and increases mediYttria stabilized zirconia grinding cylindersa and mill life. Narrow bead size distribution is very important in case of high speed milling, because during milling separation of different size beads occur. If the media contains smaller and larger beads, the small ones tend to be pushed to the edge of the milling chamber and the slurry outlet, which leads to damage of the agitation bodies and chamber walls. Besides this, the larger beads damage the smaller ones, which causes deformation of small beads and accelerates the mentioned separation problem because the deformed beads move slower than the round ones.
  • Uniform and narrow bead size distribution is a key factor for high efficiency milling and uniform formulation particle distribution. If the shapes or sizes of the beads are different, the gaps between beads are different. The wider gaps allow the slurry to escape from narrow gaps which have higher shear, which leads to broadened formulation particle size distribution and decreased milling efficiency.
  • Uniform and narrow media size distribution enhances milling efficiency, makes formulation particle size distribution narrower and ensures homogeneous dispersion, moreover, increases media and mill life.    
Conditioned, shiny surface – reduced mill and media wear, less contamination
  • A special polishing process ensures high surface quality. Note the highly polished, mirror-smooth surfaces in the photos. The surfaces of the grinding bodies so smooth that you can see the reflections of the environment on the bodies. The grinding bodies are shiny initially, and their surfaces become even smoother after the first use.
  • The preconditioning makes unnecessary the running-in period with new grinding media.
  • Being low in frictionYttria stabilized zirconia grinding media coefficient, the surface of YSZ milling media are not abrasive. Low friction between bead-bead and bead-mill benefits energy saving, temperature control, and avoiding damage of the mill components. A high friction coefficient between media and mill components leads to energy loss,  excessive heat generation, and significantly increases the mill wear.
  • The mirror-smooth Y-TZP grinding bodies are easy to clean which provides reduced solvent consumption and time saving when changing product lines and minimizes cross contamination as well.
  • The extremely smooth, shiny, nearly defect-free surface of yttria-zirconia grinding media considerably reduces mill and media wear. This also reduces the contamination of the formulation.
High efficiency, long lifespan – reduced environmental impact and operational costs
  • The high efficiency of Y-TZP grinding media reduces the energy consumption of the milling process.
  • The long service life substantially reduces the consumption of milling media. This also means lower disposal costs.
  • Since the media are easily washable, the solvent consumption and recycling/disposal cost significantly decreases. Yttria sabilized zirconia grinding beads
  • The recycling and environmental costs are constantly increasing with the stricter and stricter regulations. Being a growing percentage of the production costs, the mentioned aspects cannot be ignored.
  • YSZ milling media reduce the environmental impact of the milling process: reduced consumption of energy, grinding media and solvent. Of course, this means significantly reduced operational costs.
Developed to high performance – optimization is needed
  • If you are currently using lesser grades of grinding media, you have a great deal to gain by testing YSZ media. The effect of high quality grinding media on your product quality, productivity and mill operational costs can be significant.
  • Using yttria stabilized zirconia (or any other high density media, e.g., ceria stabilized zirconia) with a low viscosity formulation will result in very rapid wear to both the media and the mill.  Therefore, you should formulate your product to take advantage of the unique properties of these high-end media.
  • We recommend trials to gain experience with this high-tech ceramic grinding media and to find an optimized setup for your production line. The media size, charge, agitation speed and throughput must be balanced to the formulation. 
Due to its properties listed above, for high viscosity and high percent solid formulations and for sensitive applications yttria stabilized zirconia grinding media are far above all other grinding media and it is particularly suitable for continuously operating high energy mills.
Important questions – "Is it worth the money? What is the cost/benefit ratio?"
Yttria stablilized zirconia grinding balls and beadsYSZ grinding media are not inexpensive. This raises the questions, "Is it worth the money? What is the cost/benefit ratio?"
The answers for the above questions are the followings: "Yes. Consistent grinds, very high production rates, less contamination and very long service life make yttria stabilized zirconia grinding media cost effective for many applications. Of course, cost reducing effectiveness can be calculated as direct and indirect savings. For long runs, the initial cost of grinding media should be a less significant factor in the media selection."
These top-quality products are achieving the final goals of demanding customers, which are
  • improving the quality of their formulations,
  • increasing productivity and lifespan of grinding equipment, and
  • reducing operational costs. 

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