What does a machinability rating below 1.0 indicate?

A machinability rating below 1.0 signifies that the material is harder to machine compared to the baseline standard of 1.0, which is typically taken to represent a reference material, such as a particular type of steel. This rating is an important metric in manufacturing and machining because it evaluates how easily a material can be cut, shaped, or milled.

When the rating is below 1.0, it indicates that more difficulty, time, and possibly more specialized tooling and techniques are required to achieve the desired results. Materials that fall below this threshold might produce more wear on tools, require slower speeds or increased feed rates, and result in poorer surface finishes or dimensional accuracy. Understanding machinability ratings helps machinists and engineers choose appropriate tools and machining strategies, ensuring efficient production processes.