Top grades for hard-part turning

Sandvik Coromant is releasing two grades for interrupted hard-turning operations: CB7125 and CB7135. Available immediately, the grades complete the company’s offer for hard turning, complementing the existing CB7105 and CB7115 grades.

The latest Sandvik Coromant grades provide the ability to perform medium-to-heavy interrupted cuts and remove the hardened layer (depth of cut up to 2 mm) in case- and induction-hardened steel components, typically for the automotive industry. Here, CB7125 and CB7135 offer longer and more consistent tool life, good levels of surface finish and consistent dimensional tolerances, says the company.
CB7125 and CB7135 are optimised for turning steel materials with a hardness of 58-62 HRc. Designed for medium intermittent cutting, CB7125 features a newly developed PVD coating that provides improved wear and fracture resistance for extended tool life. This grade, which contains medium CBN content, is suitable for the turning of shaft splines and shafts with chamfered oil holes or pockets. Further applications include the facing of gears, the hard-to-soft turning of crown wheels, and the removal of hardened layers.
The CB7135 grade is pitched at the longitudinal turning of gears and shafts with un-chamfered keyways or pockets, as well as CV joint components such as the inner/outer race and cage. Featuring a high CBN content, the grade is said to offer high fracture resistance and predictable machining results.
Available for T-Max P, CoroTurn 107 and CoroTurn TR tooling systems, the grades come in both positive and negative basic shapes, with various edge preparations.
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