PCBN Inserts from Kennametal Make Hard Turning More Cost-Effective
Kennametal’s KBH10B and KBH20B grades, designed for hard turning, are available in double-sided inserts for materials as hard as 65 HRC. The polycrystalline cubic boron nitride (PCBN) grades are specially designed to deliver higher productivity and longer tool life when turning tool steels and other hardened materials, according to the company.
Robert Keilmann, turning product manager, says that the inserts are ideal for “high-volume production of hardened gears, shafts, bearings, housings and other drivetrain components, where tooling cost per part is an important metric.”
Various features are said to make the PCBN mini-tipped inserts cost-effective for turning hardened steel components. A ceramic binder structure and TiN/TiAlN/TiN coating provide extreme wear resistance even at elevated cutting speeds, the company says. A gold PVD coating makes it easier to identify when an insert needs indexing, while the numbered corners ensure that a machine operator does not inadvertently switch to a used edge. Two edge preparations in a “trumpet-style” hone the inserts for heavier and interrupted cuts, while a light hone prepares the inserts for continuous turning. Both inserts are free-cutting, extending tool life and generating surface finish values as low as 0.2 Ra. The PCBN mini tips are offered in four insert shapes — three rhomboidal and one triangular — which provide up to six cutting edges per insert.
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