Insert Material Grades & Coatings
Carbide Insert Material Grades and Coatings for Turning, Milling and Drilling
GUASS provides carbide substrate and coating grades for turning, drilling and milling applications. This page summarizes grade hardness, grain size, coating characteristics, recommended workpiece materials and machining conditions.
The final grade selection should consider the workpiece material and hardness, machining process, cutting speed, feed rate, depth of cut, machine rigidity, coolant use, and whether the operation involves continuous or interrupted cutting.
ISO Workpiece Material Groups
The ISO group identifies the material being machined, not the material of the insert. Identify the workpiece material group before comparing the available grades.
| ISO Group | Workpiece Material | Common Materials |
|---|---|---|
| P | Steel | Carbon steel and alloy steel |
| M | Stainless steel | Austenitic, martensitic and other stainless steels |
| K | Cast iron | Gray cast iron and ductile cast iron |
| S | Heat-resistant and titanium alloys | Nickel-based alloys, titanium alloys and aerospace alloys |
| N | Non-ferrous metals | Aluminum, copper and their alloys |
| H | Hardened materials | Hardened steel and high-hardness tool steel |
Turning and Drilling Coating Grades
GUASS turning and drilling inserts are available with CVD and PVD coating grades for different workpiece materials, hardness levels, machining stages, and continuous or interrupted cutting conditions.
| Grade | Coating | Materials and Machining Conditions |
|---|---|---|
| GSC33 | Yellow CVD | Suitable for most cast iron and ferrous materials. Its impact resistance supports heavier interrupted cutting and the machining of harder cast iron grades. |
| GSC33-5 | Black CVD | Suitable for cast iron, ferrous materials and carbon steel. It performs well in continuous cutting and can also accommodate light interrupted cutting. |
| GSC33-2 | Yellow-black CVD | Suitable for carbon steel, steel, cast iron, forging stock, HSS punches and difficult-to-cut ISO P materials. Recommended for continuous cutting above HRC 40. Not recommended for interrupted cutting. |
| GSC33-6 | Yellow-black CVD | Suitable for carbon steel, steel, cast iron, forging stock and HSS punches. Recommended for continuous cutting of non-heat-treated workpieces or heat-treated workpieces below HRC 39. |
| GA0120 | TiSiN PVD | Suitable for semi-finishing and finishing alloy steel, carbon steel, stainless steel and heat-resistant alloys at approximately HRC 45–55. Suitable for wet or dry cutting. |
| GA0124 | TiSiN PVD | Suitable for roughing and semi-finishing stainless steel, low-carbon alloy steel and heat-resistant alloys at approximately HRC 20–40. Suitable for wet or dry cutting. |
| GA0147 | AlTiN PVD | Suitable for carbon steel, cast iron, stainless steel and heat-resistant alloys. It can be used for interrupted cutting, grooving, parting and continuous cutting. |
| GA0157 | Silver PVD | Suitable for long continuous machining of titanium, aluminum, copper and other non-ferrous alloys. Available by custom order. |
Milling Carbide Substrate Grades
The performance of a milling insert depends on both its surface coating and carbide substrate. Substrate hardness, grain size and transverse rupture strength affect wear resistance, edge sharpness, toughness and resistance to cutting loads.
A grade should not be selected by one value alone. Workpiece material, machining conditions, cutting load and the risk of edge chipping must also be considered.
| Grade | Hardness | Grain Size | TRS | ISO Range | Characteristics and Applications |
|---|---|---|---|---|---|
| G12XF | HRA 92.7 | 0.5–0.6 μm | 320 kg/mm² (450 ksi) | — | Ultra-fine carbide grade for high-strength alloy steel and applications requiring a sharp cutting edge. |
| G10CF | HRA 92 | 0.7–0.8 μm | 290 kg/mm² (410 ksi) | — | Submicron carbide grade that retains a sharp cutting edge when machining high-strength nickel-based alloys, aerospace alloys, tool alloy steel and high-strength cast iron. |
| G15M | HRA 91.4 | 1–2 μm | 170 kg/mm² (240 ksi) | M15–M20, P20–P40 | Contains TiC and TaC for heat resistance. Suitable for carbon steel, stainless steel and alloy steel. |
| G20P | HRA 90.5 | 1–2 μm | 180 kg/mm² (255 ksi) | M20–M30, P20–P30 | Provides toughness and heat resistance for turning and milling carbon steel, alloy steel, stainless steel and cast iron. |
| G40M | HRA 89 | 1–2 μm | 260 kg/mm² (370 ksi) | M30–M40 | Contains tantalum and niobium carbide particles for heat and wear resistance. Suitable for machining high-nickel alloys. |
| G11C | HRA 89.5 | 1.5 μm | 250 kg/mm² (360 ksi) | K20–K30 | Provides impact resistance and toughness. After TiN, TiCN or TiAlN coating, it is suitable for heavy milling, turning and drilling of carbon steel and alloy steel. |
| G10KTA | HRA 92.5 | 1.3 μm | 160 kg/mm² (230 ksi) | K10 | Wear-resistant grade for cast iron, non-ferrous metals, copper and aluminum alloys. |
| G20H | HRA 92 | 0.8 μm | 240 kg/mm² (340 ksi) | K10–K20 | Provides hardness, toughness and brazability for end mills, reamers and brazed chamfering tools, as well as carbon steel, alloy steel, stainless steel, cast iron, copper, aluminum alloys and woodworking tools. |
| G6CF | HRA 93 | 0.6–0.8 μm | 211 kg/mm² (300 ksi) | K05 | Contains vanadium and chromium carbides for heat and wear resistance. Suitable for alloy steel, cast iron, alloy cast iron and aerospace alloys. |
Milling Coating Grades
PVD coating grades can be compared according to the workpiece material and hardness, machining stage, and wet or dry cutting conditions.
| Grade | Coating | Workpiece Hardness | Machining Range | Materials and Conditions |
|---|---|---|---|---|
| GA0120 | TiSiN PVD | Approx. HRC 45–55 | Semi-finishing and finishing | Alloy steel, carbon steel, stainless steel and heat-resistant alloys. Suitable for wet or dry cutting. |
| GA0124 | TiSiN PVD | Approx. HRC 20–45 | Roughing and semi-finishing | Stainless steel, low-carbon alloy steel and heat-resistant alloys. Suitable for wet or dry cutting. |
| GA0128 | TiSiN PVD | HRC 55 or higher | Semi-finishing and finishing | High-hardness alloy steel, carbon steel, stainless steel and heat-resistant alloys. Suitable for wet or dry cutting. |
| GA0129 | TiSiN PVD | — | Semi-finishing and finishing | Low-carbon alloy steel and stainless steel. Suitable for wet or dry cutting. |
| GA0145 | AlTiN PVD | Approx. HRC 25 or below | General milling | Mild steel, stainless steel, general steel and cast iron. Suitable for wet or dry cutting. |
| GA0147 | AlTiN PVD | Approx. HRC 25–35 | General machining | Carbon steel, general steel, cast iron and heat-resistant alloys. Suitable for wet or dry cutting. |
| GA0148 | AlTiN PVD | Approx. HRC 30–50 | Roughing | Carbon steel, heat-resistant alloys and large workpieces, including wind-power components. Suitable for wet or dry cutting. |
| GA0157 | Silver PVD | — | Continuous machining | Long continuous machining of titanium, aluminum and other non-ferrous alloys. Available by custom order. |
Need Help Confirming a Grade?
To help us review the available grade options, please provide:
- Machining process: turning, drilling or milling
- Workpiece material and exact material grade
- Workpiece hardness or heat-treatment condition
- Roughing, semi-finishing or finishing requirement
- Continuous or interrupted cutting
- Dry or wet cutting
- Cutting speed, feed rate and depth of cut
- Current insert grade and machining problem
The information on this page describes general grade characteristics and application ranges. Verify the selected grade under the actual machine, tooling, workpiece and cutting conditions before production use.