CBN END MILLS · HRC60+ · HIGH-PRECISION FINISHING

CBN End Mills for Hardened Material Finishing

ZHY CBN end mills are designed for precision finishing of hardened molds, high-hardness components and demanding applications requiring stable dimensional accuracy, long cutting-edge retention and fine surface quality.

The range uses the ZHY-developed NL900 CBN grade, controlled vacuum brazing, a 70% large-core design, a 20° helix and a 10° negative edge chamfer to support high-temperature stability and continuous finishing of materials above HRC60.

NL900 CBN Grade
For HRC60+ Materials
Radius Accuracy 0.003–0.005 mm
Surface Finish Ra 0.3 μm or Better

CBN End Mill Product Range

Select the cutting profile according to the machined surface, mold geometry, corner requirement and finishing toolpath.

CBN square end mill for hardened steel finishing

CBN Square End Mill

For hardened-steel flat surfaces, shallow pockets, straight walls, shoulders and precision planar finishing.

Flat Bottom · HRC60+ · Precision Finishing
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CBN ball nose end mill for hardened mold finishing

CBN Ball Nose End Mill

For hardened mold cavities, curved surfaces, lamp molds, free-form profiles and high-precision three-dimensional finishing.

Full Radius · R0.1 Available · 3D Finishing
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CBN corner radius end mill for hardened steel

CBN Corner Radius End Mill

For hardened pockets, shoulders, thin-wall parts and transition surfaces requiring reinforced corner strength and controlled radius accuracy.

Reinforced Radius · Thin-Wall Finishing · Custom R
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Recommended CBN Finishing Applications

CBN end mills are primarily used after heat treatment, when the component has reached its final hardness and requires controlled stock removal with stable surface quality.

01

Hardened Mold Finishing

Precision finishing of hardened mold cavities, inserts and detailed mold surfaces above HRC60.

02

Automotive Lamp Molds

Fine machining of headlamp molds requiring controlled radius accuracy and low surface roughness.

03

Thin-Wall Components

Low-stock finishing of thin sections where stable cutting pressure and dimensional consistency are important.

04

High-Precision Batch Production

Long cutting-edge retention supports automated production with fewer tool changes and stable part quality.

CBN Material and Tool Design Features

The CBN grade, brazing process, large-core geometry, edge preparation and precision grinding are designed specifically for high-hardness finishing applications.

01

NL900 CBN Material

The ZHY-developed NL900 grade uses an approximately 1.0 μm grain structure and a hardness specification of HV41 for finishing materials above HRC60.

02

Controlled Vacuum Brazing

The vacuum brazing process helps limit oxidation, decarburization and insert deformation while producing a stable joint between the CBN tip and tool body.

03

70% Large-Core Design

The approximately 70% core diameter increases tool rigidity and supports stable finishing of hard materials, slender features and precision mold surfaces.

04

20° Helix Geometry

The 20° helix is designed for controlled cutting engagement and stable chip formation during high-hardness finishing.

05

10° Negative Edge Chamfer

The negative chamfer strengthens the cutting edge, helps resist micro-chipping and supports longer tool life during finishing of hardened components.

06

CBN-Specific Grinding Wheels

Dedicated CBN grinding wheels are used to maintain cutting-edge sharpness, profile accuracy and consistent geometry.

07

R0.1 Minimum Tool Capability

Walter five-axis grinding supports small-radius CBN tools down to approximately R0.1 for detailed mold and micro-feature finishing.

08

Radius Accuracy of 0.003–0.005 mm

Controlled grinding and inspection support radius accuracy between approximately 0.003 and 0.005 mm, depending on tool size and profile.

09

Ra 0.3 μm or Better Surface Quality

Under suitable finishing conditions, the tool can support machined surface roughness of approximately Ra 0.3 μm or better.

10

High Thermal Stability

CBN retains hardness and cutting stability at elevated temperatures, making it suitable for continuous finishing of hardened ferrous materials.

11

Chemical Stability with Ferrous Materials

CBN offers greater chemical stability with iron-based materials than diamond cutting tools, supporting high-hardness steel finishing.

12

Long Cutting-Edge Retention

Under suitable finishing conditions, tool life may reach approximately 20 machining hours while maintaining stable edge quality and dimensional accuracy.

How to Select the CBN End Mill Profile

Select the cutting profile according to the final surface, corner geometry and machining path rather than choosing only by tool diameter.

Choose a Square End Mill For

  • Flat mold surfaces
  • Shallow pockets
  • Straight side walls
  • Shoulders and planar finishing
  • Defined flat-bottom features

Choose a Ball Nose End Mill For

  • 3D mold cavities
  • Curved and free-form surfaces
  • Automotive lamp molds
  • Inclined and transition surfaces
  • High-precision contour finishing

Choose a Corner Radius End Mill For

  • Pocket-bottom transitions
  • Reinforced cutting corners
  • Thin-wall components
  • Shoulders with a defined radius
  • Semi-finishing and finishing

Recommended Workpiece Materials

CBN end mills are primarily intended for finishing hard materials after heat treatment. The exact grade and cutting parameters should be verified before production machining.

Hardened Steel Above HRC60
Quenched Mold Steel
High-Hardness Mold Inserts
Hardened Precision Components
Selected Graphite Mold Applications
Selected Nickel-Based Alloys

CBN tools are normally used for precision finishing with low and stable stock allowance. They are not generally intended for heavy roughing, interrupted cutting or unstable machining conditions.

CBN End Mill Technical Overview

Standard and customized CBN end mills can be supplied according to workpiece hardness, surface profile, finishing allowance and required tool reach.

Product Types Square End Mill / Ball Nose End Mill / Corner Radius End Mill
CBN Material Grade NL900
Grain Size Approximately 1.0 μm
Hardness Specification HV41
Recommended Hardness HRC60 and Above
Brazing Process Controlled Vacuum Brazing
Core Diameter Approximately 70%
Helix Angle 20°
Edge Preparation 10° Negative Chamfer
Minimum Radius Capability Approximately R0.1
Radius Accuracy Approximately 0.003–0.005 mm
Surface Finish Capability Approximately Ra 0.3 μm or Better
Main Applications Hardened Mold Finishing / Lamp Molds / Thin-Wall Components / 3D Contours / High-Precision Batch Production
Dimensions Standard Sizes / Small Radius / Long Reach / Custom Dimensions
OEM Options Custom Dimensions / Laser Marking / Customer Model Number / Private Label

Production and Precision Inspection

Precision grinding, controlled brazing and profile inspection support consistent cutting geometry and repeatable finishing performance across production batches.

NL900 Material Verification
Vacuum Brazing Control
Walter Five-Axis Grinding
Negative Chamfer Inspection
Tool Profile Measurement
Ball and Corner Radius Inspection
Cutting-Edge Appearance Inspection
Final Packaging Inspection

CBN End Mill Manufacturer and OEM Supplier

ZHY supplies standard and customized CBN end mills for cutting-tool distributors, mold manufacturers, precision machining companies and private-label tool brands.

Application and Wholesale Support

  • Square, ball nose and corner radius profiles
  • Small-radius tools down to approximately R0.1
  • Standard and long-reach configurations
  • Application review based on hardness and allowance
  • Sample tools for machining verification
  • Mixed-size and batch-order quotations

OEM and Private Label

  • Customized diameter and radius
  • Customer logo laser marking
  • Customer model and product numbers
  • Custom labels and barcode stickers
  • Private-label tool packaging
  • Packaging verification before shipment

Request a CBN End Mill Recommendation

Send us the workpiece material, final hardness, tool profile, diameter, corner or ball radius, machining allowance, required surface finish, tool reach and order quantity. Our team will review the finishing application and recommend a suitable standard or customized CBN end mill.

Request a CBN Tool Quote