Our solutions
Industrial Tools & Solutions
Industrial Tools & Solutions
Power Technique
Power Technique
Energy Storage Systems
Products and solutions
Gas generator

How to harden a chisel

Follow the guidelines below to determine which steps are needed to make your chisels perform well again.

Europe Foundries & Metal Fabrication Products Articles North America South America Industrial Tools & Solutions Atlas Copco Africa and Middle East Percussive Tools Asia Global Australia Metal & Fabrication

To keep the productivity at a maximum it’s important to sharpen the chisels when the chisel tip eventually wears out. It’s not always necessary to harden the chisel every time you sharpen it.

Check the status of your chisel:

If the chisel tip is slightly worn out you only need to sharpen it. In this case it is not necessary to have a heat treatment.

If the chisel is very worn it may be necessary to reshape it before sharpening.

  • If the chisel is through hardened and the reshaping is made carefully without inducing too much heat in the chisel, hardening afterwards is not necessary.

  • If the chisel is case hardened it’s likely that reshaping will expose the unhardened core of the chisel. It’s therefore important to harden the chisel after the reshaping.

  • If the chisel is severely damaged it can be better to reforge it instead of reshaping it.

    Hardening is always needed after reforging as the heat from the process will cause the hardening to disappear. It is recommended to sharpen the chisel after hardening: a sharp chisel will increase productivity!

    Heat treatment for chisels

    Forging and other processes should always be carried out in accordance with the following instructions.

    When reforging worn chisels and when forging a chisel to the shape wanted, be cautious to restrict the heat treatment to as small a portion of the chisel as possible, to avoid unnecessary loss of strength.


    Forging a chisel at 850-1050°C


    • Heat the chisel slowly to the temperature specified.

    • The final forging should be carried out at the lower temperature limit.

    • Let the chisel cool in dry charcoal (breeze).
    Cool down hardened chisel

    Cool down hardened chisel in a bucket with oil


    • Don't harden the chisel directly from the forging heat.

    • Heat slowly from a low temperature to 800°C. The slower the heating process is the better the hardening of the chisel.

    • Cool the chisel in oil.
    Tempering chisel

    Tempering a chisel at 220°C


    • Temper the chisel for one hour at the temperature specified.

    • After hardening and tempering, the chisel will have the hardness of 55 to 58 HRC.

    Heat treatment not carried out in the prescribed manner may result in an excessively brittle chisel tip that can chip or crack. An incorrect heat treatment can also lower chisel hardness, leading to rapid wear or deformation of the chisel tip.

    Learn more about our Percussive Tools here