Description
Product Overview
This CBN square end mill is designed for precision finishing
of HRC60+ hardened steel, quenched mold components, flat
surfaces, shallow pockets, straight side walls, shoulders
and thin-wall features.
The tool uses the ZHY-developed NL900 CBN grade, controlled
vacuum brazing, a 70% large-core design, a 20° helix and
a 10° negative cutting-edge chamfer. This combination supports
high tool rigidity, stable edge retention and consistent
finishing of high-hardness materials.
Recommended Machining Applications
The flat-end cutting profile is intended for controlled
finishing operations requiring planar surfaces, straight
walls and defined flat-bottom features after heat treatment.
Flat Surface Finishing
Suitable for precision finishing of hardened mold
surfaces, planar inserts and flat component features.
Shallow Pocket Finishing
Designed for low-stock finishing of shallow pockets
and recessed features requiring a flat machined bottom.
Shoulder and Side-Wall Finishing
Supports straight side walls, shoulders and stepped
features in hardened mold components.
Thin-Wall Component Finishing
Suitable for stable low-allowance machining of
thin-wall and precision features where dimensional
consistency is important.
Why Use a CBN End Mill for Hardened Steel?
After heat treatment, conventional carbide tools may experience
rapid wear, loss of edge sharpness and unstable surface quality.
CBN provides high hot hardness, wear resistance and chemical
stability when machining hardened ferrous materials.
High-Hardness Finishing Performance
- Designed for hardened materials above HRC60
- High hot-hardness retention during continuous cutting
- Strong resistance to abrasive edge wear
- Suitable for low and stable finishing allowance
- Supports long continuous machining cycles
- Reduces frequent tool replacement in batch production
Surface and Dimensional Stability
- Sharp and stable cutting edge for precision finishing
- Supports approximately Ra 0.3 μm or better
- Reduced variation between production parts
- Suitable for automated high-precision machining
- Helps maintain consistent flatness and profile quality
- Rigid toolholding and stable machines are recommended
CBN Square End Mill Design and Cutting Performance
The CBN material, vacuum brazing process, large-core geometry,
negative edge preparation and precision grinding work together
to support stable finishing of hardened components.
NL900 CBN Material
The ZHY-developed NL900 material is selected for
precision finishing of hardened materials above HRC60.
Approximately 1.0 μm Grain Structure
The controlled grain structure supports consistent
cutting-edge formation, wear resistance and stable
finishing performance.
HV41 Hardness Specification
The NL900 grade uses an HV41 hardness specification
for machining high-hardness mold materials and
precision hardened components.
Controlled Vacuum Brazing
Vacuum brazing helps reduce oxidation, decarburization
and CBN insert deformation while producing a stable
brazed connection.
Reduced Brazing Deformation
Controlled temperature and vacuum conditions help
maintain CBN cutting-section position and reduce
geometry variation during brazing.
70% Large-Core Design
The approximately 70% core diameter increases cutter
rigidity and helps reduce deflection during hardened
steel 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 tool life.
CBN-Specific Grinding Wheels
Dedicated CBN grinding wheels are used to control
cutting-edge sharpness, profile consistency and
edge preparation.
Flat-End Cutting Profile
The square cutting profile supports planar surfaces,
shallow pockets, straight walls, shoulders and
defined flat-bottom features.
High Thermal Stability
CBN retains cutting hardness at elevated temperatures,
supporting stable 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.
Strong Wear Resistance
High abrasion resistance helps maintain cutting-edge
geometry during long finishing cycles.
Long Cutting-Edge Retention
Under suitable finishing conditions, continuous tool
life may reach approximately 20 machining hours while
maintaining usable edge quality.
Walter Five-Axis Grinding
Walter five-axis precision grinding supports stable
dimensions, consistent cutting geometry and repeatable
production quality.
High-Precision Batch Machining
Stable edge retention helps reduce tool changes and
supports automated, high-precision batch production.
Surface Finish and Tool-Life Capability
Actual surface finish and tool life depend on workpiece
hardness, machining allowance, spindle runout, tool overhang,
cutting parameters and machine stability.
Surface Finish Capability
- Approximately Ra 0.3 μm or better under suitable conditions
- Suitable for lamp molds and precision mold surfaces
- Supports stable planar and shoulder finishing
- Suitable for low and uniform machining allowance
- Helps reduce subsequent polishing requirements
- Machine and holder runout should be tightly controlled
Extended Tool-Life Potential
- High resistance to abrasive wear
- Stable cutting edge during continuous finishing
- Tool life may reach approximately 20 machining hours
- Fewer tool changes in automated production
- Improved consistency across machining batches
- Final life depends on the complete cutting condition
Recommended Operating Conditions
CBN square end mills are intended for precision finishing
rather than heavy roughing. Stable machining conditions
are essential for preventing edge chipping.
Recommended Applications
- Hardened material after final heat treatment
- Low and consistent finishing allowance
- Continuous or stable cutting engagement
- High-rigidity machine and toolholder
- Low spindle and holder runout
- Automated precision production
Conditions to Avoid
- Heavy roughing and large stock removal
- Strong interrupted cutting
- Unstable workpiece clamping
- Excessive tool overhang
- Severe spindle or holder runout
- Unexpected scale or hard inclusions
Standard and Custom CBN Square End Mill Sizes
Standard diameters, small cutting profiles, long-reach
configurations and customized dimensions are available
according to the hardened component and finishing allowance.
| Tool Diameter | Standard Metric Sizes / Custom Diameter |
|---|---|
| Cutting Profile | Square / Flat Bottom |
| 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 |
| Corner Design | Sharp Corner / Custom Micro Radius Where Applicable |
Send us the workpiece material, final hardness,
tool diameter, cutting length, neck length,
overall length, finishing allowance and order quantity
to receive a suitable size recommendation and quotation.
Technical Specifications
Standard and customized CBN square end mills can be supplied
according to workpiece hardness, finishing allowance,
surface requirement and tool reach.
| Tool Type | CBN Square 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 |
| 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 |
Flat Surface Finishing / Shallow Pockets / Side Walls / Shoulders / Thin-Wall Finishing |
| Dimensions |
Standard Sizes / Short Cutting Edge / Long Neck / Custom Dimensions |
| OEM Options |
Custom Dimensions / Laser Marking / Customer Model Number / Private Label |
Recommended Workpiece Materials
This CBN square end mill is primarily designed for
high-hardness finishing. Application testing is recommended
for non-standard or difficult-to-machine materials.
CBN Square End Mill Manufacturer and OEM Supplier
ZHY supplies standard and customized CBN square end mills
to cutting-tool distributors, mold manufacturers,
precision machining companies and private-label tool brands.
Application and Wholesale Support
- Standard and customized tool dimensions
- Application review based on workpiece hardness
- Small cutting profiles and long-neck tools
- Sample tools for finishing verification
- Mixed-size and batch-order quotations
- Finishing allowance and surface review
OEM and Private Label
- Customized diameter and cutting length
- Customer logo laser marking
- Customer model and product numbers
- Custom labels and barcode stickers
- Private-label tool packaging
- Packaging verification before shipment
Production and Precision Inspection
Controlled brazing, five-axis grinding and profile inspection
support consistent cutting geometry, edge quality and
repeatable finishing performance.
Request a CBN Square End Mill Recommendation
Send us the workpiece material, final hardness,
tool diameter, 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 square end mill.
