Description
Product Overview
This CBN corner radius end mill is designed for precision
finishing of HRC60+ hardened steel, quenched mold pockets,
shoulders, flat-bottom features, thin-wall components and
controlled wall-to-bottom radius transitions.
The reinforced corner radius improves cutting-edge strength
compared with a sharp square corner while retaining a
flat-bottom cutting profile. The ZHY-developed NL900 CBN
grade, controlled vacuum brazing, 70% large-core design,
20° helix and 10° negative cutting-edge chamfer work together
to support tool rigidity, edge retention and stable finishing.
Recommended Machining Applications
The flat-bottom profile and reinforced cutting corner are
suitable for high-hardness components requiring planar
surfaces, defined internal radii and stable corner strength.
Hardened Mold Pockets
Suitable for precision finishing of quenched mold
pockets requiring a flat bottom and a controlled
internal corner radius.
Shoulder Finishing
Designed for hardened shoulders, stepped features
and wall-to-bottom transitions requiring stronger
corner geometry than a sharp square end mill.
Thin-Wall Components
Supports low-allowance finishing of thin-wall
hardened components where stable cutting pressure
and dimensional consistency are important.
Radius Transition Finishing
Suitable for precise transition radii between
planar bottoms, shoulders and vertical side walls.
Why Use a CBN Corner Radius End Mill?
A corner radius end mill combines a flat-bottom cutting
profile with a reinforced corner. This makes it suitable
for finishing hardened pockets and shoulders where both
dimensional control and corner strength are required.
Reinforced Cutting Corner
- Radius reduces stress concentration at the tool corner
- Improves resistance to cutting-edge micro-chipping
- More robust than a sharp square cutting corner
- Suitable for hardened pocket and shoulder finishing
- Supports longer continuous finishing cycles
- Custom corner radii are available
Flat-Bottom and Radius Control
- Retains a flat-bottom cutting profile
- Produces controlled wall-to-bottom transitions
- Radius accuracy of approximately 0.003–0.005 mm
- Suitable for low and uniform finishing allowance
- Supports repeatable hardened mold features
- Low spindle and holder runout are recommended
CBN Performance in Hardened Steel Finishing
CBN provides high hot hardness, wear resistance and chemical
stability with ferrous materials. These properties help
maintain cutting-edge geometry during long finishing cycles
on hardened components.
High-Hardness Cutting Capability
- Designed for hardened materials above HRC60
- High thermal stability during continuous cutting
- Strong resistance to abrasive cutting-edge wear
- Suitable for low and stable finishing allowance
- Supports continuous precision machining
- Reduces frequent tool replacement
Surface and Dimensional Stability
- Supports Ra 0.3 μm or better under suitable conditions
- Stable corner radius across repeated machining cycles
- Reduced variation between production components
- Suitable for automated high-precision production
- Helps maintain pocket and shoulder consistency
- May reduce subsequent manual polishing requirements
CBN Corner Radius Geometry and Cutting Performance
The NL900 CBN material, controlled brazing, large-core
structure, reinforced radius and negative edge preparation
are designed for stable finishing of high-hardness components.
NL900 CBN Material
The ZHY-developed NL900 material is selected for
precision finishing of hardened steels and mold
components above HRC60.
Approximately 1.0 μm Grain Structure
The controlled CBN grain structure supports
consistent cutting-edge formation, wear resistance
and stable finishing performance.
HV41 Hardness Specification
The NL900 grade uses the HV41 hardness specification
for high-hardness mold and precision component
finishing.
Controlled Vacuum Brazing
Vacuum brazing helps reduce oxidation,
decarburization and CBN cutting-section deformation
while producing a stable brazed connection.
Reduced Brazing Deformation
Controlled temperature and vacuum conditions help
maintain the position of the CBN cutting section
and reduce profile variation during brazing.
70% Large-Core Design
The approximately 70% core diameter increases tool
rigidity and helps reduce deflection during hardened
pocket and shoulder finishing.
20° Helix Geometry
The controlled 20° helix supports stable cutting
engagement and predictable chip formation during
high-hardness finishing.
10° Negative Edge Chamfer
The negative chamfer strengthens the cutting edge,
improves resistance to micro-chipping and supports
longer finishing life.
Reinforced Corner Radius
The controlled corner radius reduces stress
concentration and provides stronger edge support
than a sharp square cutting corner.
Flat-Bottom Cutting Profile
The cutting profile supports flat pocket bottoms,
shoulders and planar hardened surfaces while
retaining a defined internal radius.
R0.1 Minimum Radius Capability
Walter five-axis precision grinding supports
corner radius tools down to approximately R0.1
for detailed mold and small-feature finishing.
Radius Accuracy of 0.003–0.005 mm
Controlled grinding and profile inspection support
corner radius accuracy between approximately
0.003 and 0.005 mm, depending on tool size.
CBN-Specific Grinding Wheels
Dedicated CBN grinding wheels are used to control
cutting-edge sharpness, corner-radius consistency
and negative edge preparation.
High Thermal Stability
CBN retains cutting hardness at elevated
temperatures, supporting continuous finishing
of hardened ferrous materials.
Chemical Stability with Ferrous Materials
CBN provides greater chemical stability with
iron-based materials than diamond cutting tools,
making it suitable for hardened steel finishing.
Walter Five-Axis Grinding
Walter five-axis precision grinding supports
stable dimensions, consistent radius profiles
and repeatable production quality.
Surface Finish and Corner Radius Accuracy
Actual surface quality and radius accuracy depend on the
workpiece hardness, finishing allowance, spindle runout,
tool overhang, cutting parameters and overall machine rigidity.
Surface Finish Capability
- Approximately Ra 0.3 μm or better under suitable conditions
- Suitable for high-precision hardened mold surfaces
- Supports flat-bottom and shoulder finishing
- Suitable for low and uniform machining allowance
- May reduce subsequent polishing requirements
- Stable workholding and machine conditions are essential
Corner Radius Control
- Radius accuracy of approximately 0.003–0.005 mm
- Walter five-axis precision profile grinding
- CBN-specific grinding wheel process
- Corner radii down to approximately R0.1
- Supports repeatable wall-to-bottom transitions
- Low holder and spindle runout are required
Long Tool Life for Automated Finishing
High wear resistance and stable cutting-edge retention make
CBN suitable for continuous finishing and automated production
where frequent tool replacement can reduce machining output.
Tool-Life Potential
- Strong resistance to abrasive cutting-edge wear
- Stable corner geometry during long finishing cycles
- Tool life may reach approximately 20 machining hours
- Fewer tool changes during continuous production
- Improved consistency between machining batches
- Actual tool life depends on the complete cutting condition
Batch Production Benefits
- Supports automated high-precision machining
- Reduces machine interruptions for tool changes
- Helps maintain stable radius dimensions
- Supports consistent pocket and shoulder quality
- Suitable for repeat production of hardened parts
- Application verification is recommended before mass production
Recommended Operating Conditions
CBN corner radius end mills are intended for precision
semi-finishing and finishing rather than heavy roughing.
Stable machining conditions help reduce the risk of edge chipping.
Recommended Applications
- Workpieces after final heat treatment
- Hardened material above HRC60
- Low and consistent machining allowance
- Continuous or stable cutting engagement
- High-rigidity machine and toolholder
- Automated precision mold finishing
Conditions to Avoid
- Heavy roughing and large stock removal
- Severe interrupted cutting
- Unstable workpiece clamping
- Excessive tool overhang
- Severe spindle or holder runout
- Unexpected scale, gaps or hard inclusions
Standard and Custom CBN Corner Radius End Mill Sizes
Standard diameters, small corner radii, long-neck tools
and customized dimensions are available according to
the mold geometry, finishing allowance and required reach.
| Tool Diameter | Standard Metric Sizes / Custom Diameter |
|---|---|
| Corner Radius | Standard Radius / Small Radius / Custom Radius |
| Minimum Radius Capability | Approximately R0.1 |
| Cutting Length | Standard / Short Cutting Edge / Custom |
| Neck Length | Standard / Long Neck / Custom |
| Shank Diameter | Standard Shank / Custom Shank |
| Overall Length | Standard / Extended Reach / Custom |
Send us the workpiece material, final hardness,
tool diameter, corner radius, cutting length,
neck length, overall length, finishing allowance,
required surface quality and order quantity to
receive a suitable recommendation and quotation.
Technical Specifications
Standard and customized CBN corner radius end mills can
be supplied according to workpiece hardness, pocket geometry,
required radius, finishing allowance and tool reach.
| Tool Type | CBN Corner Radius End Mill |
|---|---|
| CBN Material Grade | NL900 |
| CBN Grain Size | Approximately 1.0 μm |
| Hardness Specification | HV41 |
| Recommended Workpiece Hardness | HRC60 and Above |
| Brazing Process | Controlled Vacuum Brazing |
| Core Diameter | Approximately 70% |
| Helix Angle | 20° |
| Edge Preparation | 10° Negative Chamfer |
| Minimum Corner Radius Capability | Approximately R0.1 |
| Corner Radius Accuracy | Approximately 0.003–0.005 mm |
| Grinding Process | CBN-Specific Precision Grinding |
| Surface Finish Capability | Approximately Ra 0.3 μm or Better |
| Tool-Life Potential |
Up to Approximately 20 Machining Hours Under Suitable Finishing Conditions |
| Main Operations |
Hardened Pocket Finishing / Shoulder Finishing / Flat-Bottom Features / Thin-Wall Finishing / Radius Transition Finishing |
| Dimensions |
Standard Sizes / Small Radius / Long Neck / Custom Dimensions |
| OEM Options |
Custom Dimensions / Custom Radius / Laser Marking / Customer Model Number / Private Label |
Recommended Workpiece Materials
This CBN corner radius end mill is primarily designed
for high-hardness finishing. Application testing is
recommended for selected nickel-based alloys, graphite
molds and other non-standard materials.
CBN Corner Radius End Mill Manufacturer and OEM Supplier
ZHY supplies standard and customized CBN corner radius
end mills to cutting-tool distributors, mold manufacturers,
precision machining companies and private-label tool brands.
Application and Wholesale Support
- Standard and customized corner radii
- Application review based on hardness and pocket geometry
- Small-radius tools down to approximately R0.1
- Standard, long-neck and extended-reach tools
- Sample tools for finishing verification
- Mixed-size and batch-order quotations
OEM and Private Label
- Customized diameter and corner radius
- Customer logo laser marking
- Customer model and product numbers
- Custom labels and barcode stickers
- Private-label tool packaging
- Packaging verification before shipment
Production and Corner Radius Inspection
Controlled brazing, five-axis grinding and corner-profile
inspection support consistent radius geometry, cutting-edge
quality and repeatable finishing performance.
Request a CBN Corner Radius End Mill Recommendation
Send us the workpiece material, final hardness,
tool diameter, required corner radius, cutting length,
machining allowance, required surface finish,
tool reach, machine condition and order quantity.
Our team will review the finishing application and
recommend a suitable standard or customized CBN
corner radius end mill.
