6mm Balls | McMaster-Carr

Multipurpose Low-Carbon Steel—Low-carbon steel balls are our easiest steel balls to machine. They are often used for parts that don’t require high strength, such as knobs. These balls can be surface hardened with heat treating for added wear resistance.

Wear-Resistant 52100 Alloy Steel—High carbon and chromium content makes this 52100 alloy steel extremely hard and resistant to wear. It’s also known as chrome steel. Often used as bearings, these balls are hardened for increased abrasion and impact resistance.

	Dia. Tolerance, mm	Heat Treatment	Yield Strength, psi	Mechanical Finish	Hardness	Appearance	Pkg. Qty.		Pkg.
Multipurpose Low-Carbon Steel



	6	-0.13 to 0.13	Case Hardened	44,000	Tumbled	Rockwell C60 (Extra Hard)	Mirror Like	250	96455K133	000000


	Wear-Resistant 52100 Alloy Steel



			6	-0.0025 to 0.0025	Hardened	295,000	—	Rockwell C60 (Extra Hard)	Mirror Like	50	9292K41	0000

Hardened Ultra-Wear-Resistant 440C Stainless Steel Balls

The best choice for high-performance bearings and valves, these 440C stainless steel balls are among the strongest, hardest, and most wear-resistant we offer. They’re passivated to wash away surface particles that cause rust, and they’re polished to a mirror-like finish that contaminants can’t stick to. The result is balls that stay smooth and stand the test of time—even at temperatures up to 800° F. They’re made to strict ISO 3290 standards for roundness and surface quality.

These balls are magnetic, so you can use them in separators, sensors, and automated handling systems that use magnetic pickup or positioning.

Grade 25—Precision-ground to tighter tolerances than Grade 100 balls. Use them in high-accuracy assemblies.

Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.

							Stainless Steel Balls			5 lb. Packs of Stainless Steel Balls
	Dia., mm	Dia. Tolerance, mm	Hardness	Specs. Met	Magnetic Properties	Appearance	Pkg. Qty.		Pkg.	Pkg. Qty.		Pkg.
Grade 25



		6	-0.0025 to 0.0025	Rockwell C58 (Extra Hard)	ISO 3290	Magnetic	Mirror Like	50	1598K27	000000	2,570	1598K271	0000000

Multipurpose 304 Stainless Steel Balls

Whether inside pumps or furnace parts, these balls can be used in any mildly corrosive, high-temperature conditions. Made of 304 stainless steel, they won’t degrade when exposed to mild chemicals and water, even at temperatures up to 1500° F. They’re passivated to wash away surface particles that cause rust, and they’re polished to a mirror-like finish that contaminants can’t stick to. The result is balls that stay smooth and stand the test of time. These balls are made to strict ISO 3290 standards for roundness and surface quality.

Although 304 balls aren’t as wear resistant as 440C balls, they’re easier to fabricate. They’re also nonmagnetic.

Grade 100—Great for mechanical applications where you don’t need the exacting tolerances of Grade 25.

Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.

								Stainless Steel Balls
	Dia., mm	Dia. Tolerance, mm	Fabrication	Hardness	Specs. Met	Magnetic Properties	Appearance	Pkg. Qty.		Pkg.
Grade 100



		6	-0.0127 to 0.0127	Cold Worked	Rockwell C25 (Hard)	ASTM A240, ISO 3290, SAE J405	Nonmagnetic	Mirror Like	50	9291K77	00000

Extra-Hard C2 Tungsten Carbide

Machine long-lasting tools, such as end mills and inserts, with this Tungsten. Tungsten carbide, sometimes called carbide, is harder than our Corrosion-Resistant Tungsten with excellent wear resistance. Its extreme hardness lets cutting edges stay sharp far longer than high-speed steel.

Balls

Dia. Tolerance, mm	Mechanical Finish	Yield Strength	Hardness	Temper Rating	Pkg. Qty.		Pkg.



6	-0.0025 to 0.0025	Polished	Not Rated	Rockwell C75 (Extra Hard)	Not Rated	2	9686K87	000000

Highly Corrosion-Resistant 316 Stainless Steel Balls

Trusted in marine and chemical-processing valves, these balls stand up to some of the most highly corrosive environments. Made of 316 stainless steel, they hold up to sulfuric acid, chlorine, and other harsh chemicals in temperatures as high as 1500° F. They’re a step up from balls made of 304, which have similar strength and temperature performance. They’re passivated to wash away surface particles that cause rust, and they’re polished to a mirror-like finish that contaminants can’t stick to. The result is balls that stay smooth and stand the test of time. They’re made to strict ISO 3290 standards for roundness and surface quality.

Although 316 balls aren’t as wear resistant as 440C balls, they’re easier to fabricate. They’re also nonmagnetic.

Grade 100—Great for mechanical applications where you don’t need the exacting tolerances of Grade 25.

Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.

								Stainless Steel Balls
	Dia., mm	Dia. Tolerance, mm	Mechanical Finish	Hardness	Specs. Met	Magnetic Properties	Appearance	Pkg. Qty.		Pkg.
Grade 100



		6	-0.013 to 0.013	Tumbled	Rockwell C25 (Hard)	ISO 3290	Nonmagnetic	Mirror Like	50	96415K588	00000

Plastic Balls

Nylon—Use these nylon 6/6 balls as bearings and in sealing applications. They have a slippery surface that reduces wear caused by friction.

Torlon PAI—Dimensionally stable and slippery, these balls are often used in high-friction applications, such as nonlubricated rollers and ball bearings.

	Max. Temp.	Color	Flammability Rating	Pkg. Qty.		Pkg.
Wear Resistant







	Nylon

	6	-0.001" to 0.001"	Not Rated	Not Rated	Off-White	—	25	9613K52	000000


	Flame Retardant, Wear Resistant







					Torlon PAI

					6	-0.0254 mm to 0.0254 mm	Not Rated	450° F	Green	UL 94 V-0	10	9593K26	0000

Tumbling Media for Steel, Stainless Steel, and Hard Metals

Ball

Made of a hard material, this tumbling media is tough enough to finish steel, stainless steel, and other hard metal parts. Choose the shape that best matches the contours of your part and a size that’s large enough not to get stuck in recesses and holes. You can also mix shapes and sizes to tailor the finish to your part.

For Mirror Finish—Use this media as the final step in your finishing process to create a reflective finish. Ideal for fragile parts, it rubs the surface without removing material.

Ball—Best for gentle finishing. Balls are less aggressive than other shapes, so they smooth your workpiece without flattening any details.

Wet Tumbling Condition—Use this media with liquid cleaners.

							5 lb.
	Dia., mm	Density, lb/ft³	Recommended Media to Parts Ratio	Abrasion Type	Tumbling Condition	Material		Pkg.
For Mirror Finish







				Ball

				6	125	3:1	None	Wet	Porcelain	4334A35	000000