A new development in chipbreaker design especially for light duty finish turning of super-alloy and hardened steel-type materials involving low cutting forces is now available through Sumitomo Electric Hardmetal in Princess Risborough.

The New NSI inserts have been developed for finish turning and facing with high orders of chip control giving greater levels of turning stability and predictability on typical components used in the medical and high precision machining sector. Typical operations for the new tooling are those where CNC sliding head machines are involved. The NSI insert incorporates a nose radius having a ‘minus tolerance’, a high rake angle and is produced to ‘G-Class’ precision.

Sumitomo has added the new chipbreaker format to the highly successful positive relief inserts designated CCGT, DCGT, TCGT and VCGT. This range of inserts are available with Sumitomo’s multi-layer ZX PVD structured coating on both cermet and carbide base material with both types having a ‘bumpy’ chipbreaker style.

CCGT is an 80 deg, 7 deg relief diamond-shaped insert, DCGT 55 deg, 7 deg relief diamond, TCGT 60 deg with 0 deg relief and VCGT a 35 deg, 7 deg relief diamond insert.

The ZX nano layer coating of TiAIN and AlCrN creates a surface hardness some 40 per cent higher with a 200 deg C higher resistance level to oxidation. ZX coated tools are also able to run at 1.5 times higher speed with the added value of double the tool-life of conventional grades.