Cutting It Fine

Advancements in Milling and Turning Tools Come With a Certain Level of Modernity

- Jayashree Kini Mendes

MILLING AND TURNING HAS COME A LONG way from merely being up on machines and running them on objects. According to a science website, circumstantial evidence for early tools rose years ago. Scraps of animal bones dated to around 3.4 million years ago bear slice marks that seem to be intentional.

Materials of tools too have evolved. From steel, it has come a long way to diamond coating and somewhere along the way carbide, ceramic, cemented carbide and several others were a part of the cutting tools. However, certain materials exhibit poor machineability due to their low thermal conductivity, potential for adhering to cutting tools and the presence of abrasive particles within the alloy structure. L Krishnan, MD, TaeguTec India, says, “Machinability of different materials vary based on composition, grain structure and heat treatment. Realising this, several years ago, ISO classification according to application grouped them under six broad categories: P/M/K/N/S/H.”

Each category would mean the following:

• P: for long chipping material like steel

• M: Stainless steel and similar materials

• K: For cast iron and short chipping materials

• N: Non-ferrous

• H: Hard materials

• S: Super alloys