To help manufacturers enjoy benefits such as reduced cycle times and greater tool life when performing hard-part turning, Halesowen-based Sandvik Coromant has strengthened its existing offer in the ISO H05 to H15 application area with the introduction of two new grades — CB7105 and CB7115 (www.sandvik.coromant.com).

These will be of particular benefit to those machining transmission components for the automotive industry, where lower cost per part can be achieved, says the company.

With CB7105, Sandvik Coromant claims to have created a grade for hard-part turning that offers enhanced resistance to crater wear than existing solutions, while CB7115 is designed to provide better fracture resistance.

Both grades are based on a PCBN material and coating, with inserts featuring an “appropriately adjusted” edge preparation.

Sandvik Coromant product manager Torbjörn Ågren says: “CB7105 allows machine shops to achieve lower cost per part when used as part of a high-speed machining strategy.

“Alternatively, users of this grade can benefit from longer tool life at lower speeds. CB7115 is also designed to deliver lower cost per component, typically though the adoption of one-cut strategies at higher speeds.”

In one trial, the output of case-hardened 16MnCrS5 (57-62HRc) automotive components increased by at least 15% after switching to CB7105 and CB7115.

In fact, CB7115 produced more than 600 components (at 0.15min in-cut time) with predictable surface finish and lower Rz value. The cutting speed was 170m/min, while the feed rate was 0.22mm/rev and the cutting depth 0.15mm.