Most Common Ball Materials

Ball Technical Data Sheet #1 — Metals Used to Manufacture Balls

Metal Manufactured from Magnetism Machinability Hardness
Aluminum Aluminum Assoc. Spec. No. 2017, SAE No. 26 Non-magnetic Easily machined, drilled and tapped 54-72 HRB
Brass Copper 60-70%, Zinc 30-40% Nearly non-magnetic Easily machined, drilled and tapped 75-87 HRB
Chrome Steel Steel of the through hardening type AISI E-52100, The most commonly used ball material Strongly attracted by magnet Can be drilled by EDM and modified by grinding 60-67 HRC
Hardened Stainless Steel Steel AISI type 440C Strongly attracted by magnet Can be drilled by EDM and modified by grinding 58-65 HRC
Soft Mild Steel Steel AISI type 1018 Strongly attracted by magnet Easily drilled, machined, tapped, and welded 28 HRC
Tungsten Carbide Tungsten Carbide 93.5 - 94.5%, Cobalt 5.5-6.5% Slightly magnetic This material is not easily machinable, use EDM or diamond grinding 87.5 - 90.4 HRA
Unhardened Stainless Steel Steel AISI type 316 or 302 Only slightly magnetic May be machined, drilled and tapped 30 HRC
Chrome Alloy Steel Balls,
the most common bearing alloy, are manufactured from steel of the hardening type AISI E-52100. The balls are heat treated to a hardness of 62 HRC minimum. They are strongly attracted by a magnet.
Hardened Stainless Steel Balls
are widely used in bearings and valves, and are manufactured from steel AISI type 440C. Hardness is 58 HRC minimum. They are strongly attracted by a magnet.
Unhardened Stainless Steel Balls
are manufactured from steel AISI Type 316 or 302. This material is only slightly magnetic. It may be machined, drilled, and tapped. It has the best corrosion resistance of the standard metals. Hardness is about 30 HRC.
Brass Balls
are widely used in tooling and are manufactured from Copper 60-70%, Zinc 30-40%. They are easy to machine, drill, and tap. This material is nearly nonmagnetic. Hardness is 80 HRB.
Soft Mild Steel Balls
are manufactured from steel, AISI type 1018. They are strongly attracted by a magnet. Soft mild steel is easy to machine, drill, and tap. The balls are highly polished for decorative applications etc. Hardness 28 HRC.
Aluminum Balls
are manufactured from Aluminum Association Specification No. 2017 (SAE No.26). The material is nonmagnetic. It is easy to machine, drill, and tap.
Tungsten Carbide Balls
are manufactured from high grade material in the range of Tungsten Carbide 93.5-94.5%, Cobalt 5.5-6.5%. The balls may be ground with diamond wheels and shaped with electro discharge machines. This is one of the hardest, toughest, and most rigid materials available. It is slightly magnetic.

See our web page, Ball Material Selection, for more information.

Ball Technical Data Sheet #2 — Plastics Used to Manufacture Balls

Plastic Resistant to Physical Properties Maximum Usable Temperature Specific Gravity Water Absorption
Nylon Oils, greases, electrolytic corrosion and most organic solvents High Tensile strength, abrasion resistant, high compression strength, low coefficient of expansion, very good electrical properties 360 °F. 1.09 - 1.14 Is hygroscopic and absorbs considerable amounts of water, .4 -1.5%
Polyethylene Bases, weak acids, and organic solvents ( except chlorinated ones ) Attacked slowly by oxidizing acids 175 ° F .90 - .91 low water absorption, low density, will float in water, .02%
Polypropylene Bases, weak acids, and organic solvents about 80 °C Attacked slowly by oxidizing acids 320° F .90 - .91 low water absorption, low density, will float in water, .01%
PTFE Practically all organic solvents, strong caustics, cryogenic missile fuels, liquid oxygen, and concentrated acids Good physicals from cryogenic temperatures to over 500 °F, good compressive strength 550 °F 1.13 - 2.22 zero water absorption 0% < .01 %
Nylon Balls
are resistant to most common organic solvents, oils, greases and electrolytic corrosion. Nylon has a good heat resistance, high tensile strength, fatigue endurance, compression and shear strength, abrasion resistance, low coefficient to friction and very good electrical properties.
PTFE Balls
are unaffected by practically all organic solvents, strong caustics, cryogenic missile fuels, liquid oxygen and concentrated acids. They have zero water absorption, while maintaining the highest heat resistance of all thermoplastics. PTFE has good physicals with cryogenic temperatures to +500 °F and good compressive strength.
Click to see our PTFE ball stock in our shopping cart.
Polyethylene Balls
are resistant to organic solvents, except chlorinated ones, and to bases and weak acids. They have very low water absorption, and they will float in water.
Polypropylene Balls
are resistant to organic solvents below about 80 °C, to bases and weak acids. They are only slowly attacked by oxidizing acids. They will float in water and have a low water absorption.
See our web pages, Ball Material Selection, and Sizes and Materials Used by to Manufacture Balls for more information.
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