
HEX Series End mill for hardened steel
HEX Square End Mill for Hardened Steel HRC60–68
Range reference: KVX-015
- workpiece material
- Hardened Steel
- application type
- Semi-Finishing; Finishing
- flute type
- Square End Mill
- Coating
- DR3
• Carbide: Ultra-fine grain carbide, 0.4 μm, 9% Co • Coating: Balzas DR3, heat resistance up to 1300°C • Hardness Range: HRC 60–68 • Core Diameter: Up to 68% for high rigidity • Helix Angle: 45° • Negative Rake Angle: 0° to -5° • Application: High-efficiency side milling & finishing
Enquire about this tool →Technical data
HEX square end mills use ultra-fine carbide with 0.4 μm grain size and 9% cobalt content. This carbide substrate provides high hardness, excellent wear resistance, and enough toughness for high-hardness steel machining. It helps the tool maintain edge strength and cutting stability when machining hardened steel materials where ordinary carbide end mills may wear quickly or suffer from edge chipping. The cutter is coated with DR3 high-wear-resistant coating, with heat resistance up to 1300°C. This coating helps improve oxidation resistance, reduce friction, and extend tool life during continuous cutting of hardened steel. For HRC60–68 machining, cutting temperature and tool wear are usually critical problems. The DR3 coating helps the tool maintain stable performance under high-temperature and high-load cutting conditions. | |
The HEX square end mill adopts a large core diameter design of up to 68%, improving tool rigidity and edge support. This helps reduce tool deflection and vibration during side milling, shoulder machining, and high-speed finishing. Higher rigidity is especially important when machining hardened steel, because unstable cutting can easily lead to poor surface finish, edge damage, or shortened tool life. The tool uses a 45° helix angle together with a 0° to -5° negative rake angle. This geometry helps improve cutting stability, strengthen the cutting edge, and reduce the risk of micro-chipping in hardened steel machining. The negative rake design is especially suitable for high-hardness materials where edge strength is more important than aggressive cutting sharpness. |
Additional technical data
| Machining Task | Why HEX Square End Mill Fits |
|---|---|
| Side milling | Large core design improves rigidity and cutting stability |
| Shoulder machining | Strong edge support helps reduce micro-chipping |
| Flat surface finishing | Stable geometry supports better surface consistency |
| Contour finishing | 45° helix angle helps achieve smoother cutting |
| Hardened steel finishing | DR3 coating improves wear resistance under high cutting temperature |
| Precision mold machining | Negative rake design improves edge strength and dimensional stability |
Additional technical data
| Item | Range / Notes |
|---|---|
| Tool type | Square end mill / flat end mill |
| Hardness range | HRC60–68 |
| Diameter range | D1.0–D25.0 |
| Length options | Standard length and long shank options available |
| Typical use | Semi-finishing, finishing, high-speed machining |
| Custom service | Diameter, flute length, overall length, shank, coating, and special geometry |
Technical notes
- The HEX square end mill is specially developed for hardened steel machining from HRC60 to HRC68 . It is designed for side milling, shoulder machining, contour finishing, and precision mold applications where high rigidity, edge strength, and stable cutting performance are required.
- Compared with general-purpose square end mills, the HEX series is built for high-hardness cutting conditions. Its ultra-fine carbide substrate, high-wear-resistant DR3 coating , reinforced core geometry, and negative rake design help improve tool life, cutting stability, and surface quality in hardened steel machining.
- This tool is especially suitable for precision finishing and semi-finishing of hardened mold components, die steel parts, and high-hardness workpieces where dimensional accuracy and edge durability are critical.
- HEX square end mills are suitable for high-hardness steel machining from HRC60 to HRC68 , especially for hardened mold materials such as H13, 718H, NAK80, S136 , and similar mold steels.
- This tool is mainly used for semi-finishing and finishing applications where cutting stability, edge strength, and surface quality are required. It is suitable for hardened mold components, die steel parts, and precision high-hardness workpieces.
- Typical applications include:
- • Side milling of hardened steel components
- • Shoulder machining
- • Flat surface finishing
- • Step face machining
- • Side wall finishing
- • Contour side finishing
- • Precision mold component finishing
- • High-speed CNC finishing of HRC60–68 materials
- Recommended Application Guide
- Size Range Overview
Technical illustrations and dimension data


