HARDLOCK Bearing Nut Materials & Coatings

The HARDLOCK Bearing nut (bearing locknut) is available in common materials and can be manufactured in any material that is required. HARDLOCK Bearing nut is composed of completely one material reducing the chance of galvanic corrosion which occurs with dissimilar metals. HARDLOCK Bearing nut is very viable when a specific material must be used, and does not require plastic/ resin components which can degrade over time.

Standard materials and coatings

For HARDLOCK Bearing Nut we often hold stock in the following materials, please quote us for current information.


Equivalent Materials

Finish / Coating


AISI 1018

Manganese Phosphate Coating


AISI 1045

Manganese Phosphate Coating


SAE 304


・Low carbon steel – JIS SS400
This material is the Japanese version of AISI 1018 Steel, differing in such that the chemical composition has slightly different constraints. Also the tensile strength requirement for SS400 is 400Mpa, but for 1018 it is 440Mpa. Please use this material for applications where the nut isn`t under heavy loads. For example when locating a ball bearing with no axial loads under operation.

・Medium carbon steel – JIS S45C
Also known as SAE AISI 1045 Steel, this material is used quite commonly worldwide and is often used for nuts.

・Stainless steel – SUS304
Also known as SAE 304 stainless steel, this material is the most common stainless steel for nuts/bolts. However this material is not recommended where severe corrosion resistance can occur, in this case please use SUS316 or SUS316L..

・Manganese Phosphate Coating or what we call Parkerizing is our most common coating for carbon steel HARDLOCK Bearing Nuts. Make sure to store with corrosion preventative liquids or oils as this is not a corrosion resistant coating.

Non-standard Materials

The following materials are suggestions of materials you can inquire to get made for you. We do not hold stock in these materials. Please inquire to us first to see whether manufacturing is possible.
We are very open to any materials you propose, as long as it can be procured.