Institute for Machines Logo

Machinability Database.

Empirical ratings, Brinell hardness, and specific cutting energy coefficients for industrial alloys.

The Machinability Rating Baseline

Machinability ratings are empirical percentages based on a standard reference material: AISI 1212 cold-drawn steel, which is assigned a rating of 100%. If a material has a rating of 50%, it generally means the surface speed (SFM) must be halved compared to 1212 to achieve the same tool life.

This is a heuristic. True optimization requires calculating the Specific Cutting Energy (Unit Power).