Grinding Media

STR Industries manufacturing plant

Grinding Media Services

We have been in business for over 30 years and we know how critical the quality and the service could be especially in your type of industry.

STR Industries has been manufacturing media for 30 years. We are TS 16949(auto industry standard, higher than ISO 9001) certified Our 200,000 ft2 facilities produce more than 400 metric tons of balls per month. Our product size ranges from 0.8mm to 80mm in chrome, carbon, stainless steel, plastic and ceramics material. Grinding media plays a significant role for ink, paint and chemical manufacturers. Take the following specifications for example:

  • Ball surface finish - determining ink particle size and shape
  • Ball hardness and crushing load - determine life-time of grinding media
  • Ball Price - a penny saved is a penny earned

Our grinding media is approved by customers not only in the ink but also pigment, paste, ferrite and food industries. We have been providing customers worldwide directly with our products saving substantial amount of money. Some of our customers are BASF, Akzo Nobel, Sun Chemical, and others, and of course biggest mill manufacturers.

STR, the professional ball manufacturer, will work on your company's grinding media requirements, including ceramic grinding media and steel ball grinding media. If you are not sure what media do you need just give us a call and we will give you a free consultation and make sure that you have all information you need.

Ceramic Media

Next Generation Ceramic Media

The beads or ball, have been chosen as a media for the process of mixing, crushing, dispersing and purifying variable materials. Steel media is commonly used but can not be used for manufacturing bright colors and steel contamination could be a problem for some products. Ceramic beads reduce contamination to products and perform as well as steel.

Why Ceramic Bead?

  • Higer density
  • Reduce product contamination
  • Can be used with white or bright colors
  • Longer life expentancy
  • Significant savings and availability in nano sizes
Ceramic Bead

What is Zirconia?


Generally speaking, oxides are named by changing the suffix of the constituting metal element "-ium" to "-a" , such as alumina for aluminium oxide and titania for titanium oxide. Zirconia is therefore the same as Zirconium Oxide (Zr02).


Zirconia is used in Grinding media, Cutting Tools, Ferruls, Oxygen Sensor, Cubic Zirconia(as Jewelry) and Refractory Materials, because zirconia has high hardness, strength, toughness, excellent wear resistance (structural properties), electrical conductivity(electrical properties), and low thermal conductivity (thermal properties). Specially, Zirconia Beads make the best use of structural properties in specific characters of Zirconia.


  • FSZ (Fully Stabilized Zirconia)
  • PSZ(Partial Stabilized Zirconia)
  • TZP(Tetragonal Zircoia Polycrystal) or TTZ(Tetragonal Toughened Zirconia)
  • Zircon( Zirconium Silicate)Although the name resembles zirconia (zirconia is called "zircon" in France)

Ytrria Stabilized Zirconia

High density and hardness Yttria Stabilized Zirconia Beads ZY are offering the user higher productivity, longer mill life and lower operation cost in the long run. Available Size: 0.1, 0.3, 0.6, 0.8, 1.0, 1.5, 2.0 and 2.7 mm with 100% Round and uniformed.

Ceria Stabilized Zirconia

Ceria Stabilized Zirconia Beads CZ offers the highest density 6.2 g/cm2, optimized wear resistance and cost effectiveness for efficient milling. Available Size: 0.3, 0.6, 0.8, 1.0, 1.5, 2.0 and 2.7 mm with 100% Round and uniformed.

CompositionDensity g/cm3Bulk Density kg/lHardness HvColor
ZYZrO2 / Y2O3>6.02> 3.7>1350Ivory
CZZrO2 / CeO2>6.20> 3.9>1250Brown

Other Grinding Media

CompositionDensityBulk DensityHardnessColor
SteelSee steel info7.84.960-65 RCSilver
AluminaAl2O33.82.21600 HvWhite
ZirconZrSiO43.82.41000 HvWhite
ZYZrO2+Y2O363.61300 HvIvory
CYZrO2+CeO26.23.81200 HvBrown

By carefully considering factors such as grinding precision, the various characteristics of the different materials, and the different types of grinding machines, STR Industries can recommend the most suitable grinding media for customers, thus helping customers to achieve their ultimate goals of productivity improvement and cost reduction. We believe in maintaining favorable relationships with our customers as business partners.

Carbon Steel Ball
Chrome Steel Ball
Stainless Steel Ball
Carbon Steel Ball

Material Available

  • Low Carbon: AISI 1008~ AISI 1018
  • Medium Carbon: AISI 1045
  • High Carbon: AISI 1065~ AISI 1085
AISI NumberC %Si %Mn %Mo %P %S %Hardness
AISI 10080.10 Max0.30 Max0.50 Max0.0120.07 Max0.06 MaxCase Hardened HRC 55Min
AISI 10150.13~0.180.10~0.300.30~0.600.020.04maxCase Hardened HRC 55~61
AISI 10450.43~0.500.10~0.300.60~0.900.0250.04 Max0.05 MaxThrough Hardened HRC 60 Min
AISI 10860.83~0.880.10~0.300.30~0.700.040.04 Max0.04 MaxThrough Hardened HRC 60 Min

Chemical Composition


3 ~ 1000


1.0mm~ 2"


Casters, bicycle parts, light-duty bearing, hardware, toy and etc.

Chrome Steel Ball
C %Si %Mn %Cr %Cu %S %P %
0.90~1.050.15~0.350.25~0.451.35~1.650.3 Max0.03 Max0.03 Max

Chemical Composition


7.84 g/cm3


Through hardened, HRC 60 Min. Grade
5~ 1000 grade




Bearing, Ball Screw, Linear motion guide, Auotomotive parts, Chemical, food processing.

Stainless Steel Ball

Material Available

  • AISI 302~AISI 316
  • AISI 420~AISI 440C
AISI NumberC %Si %Mn %Cr %Ni %Mo %P %S %Character
AISI 3020.15 Max1.00 Max2.00 Max17.0~ 19.08.0~ 10.50.045 Max0.03 MaxSlightly magnetic Austinitic
AISI 3040.07 Max1.00 Max2.00 Max17.0~ 19.08.50~ 10.50.045 Max0.03 MaxSlightly magnetic Austinitic
AISI 3160.07 Max1.00 Max2.00 Max16.5~ 18.510.5~ 13.52000~ 2.500.045 Max0.03 MaxNon magnetic Austinitic Excellent corrosion resistance
AISI 420J0.17~ 0.251.00 Max1.00 Max12.0~ 14.00.045 Max0.03 Maxmagnetic Hardenable HRC 48 Min fair corrosion resistance
AISI 4300.08 max1.00 Max1.00 Max15.5~ 17.50.045 Max0.03 Maxfair- good corrosion resistance
AISI 440C0.95~ 1.201.00 Max1.00 Max16.0~ 18.00.40~ 0.800.04 Max0.02 Maxfair corrosion resistance Hardenable HRC 58 Min

Chemical Composition






Dispenser valve ball, stainless steel bearing, chemical related application