Machine-tooling hard materials such as tool steel, D2 hardened steel, and H13 hardened steel appears to be a difficult challenge for many precision engineers. However, by selecting the appropriate work holding and tool holding techniques, as well as a high-performing, purpose-made cutting tool, it can be made to appear simple.

For hardened steels HRc 50-70, a standard Micrograin Carbide substrate cannot be used because of the nature of the material. It is not only CNC milling parts the workpiece is extremely hard, but CNC milling part is also that dry machining is typically used to reduce heat fluctuations on the cutting tool. CNC milling part is necessary to use tools that contain superior grades of carbide, such as Ultrafine Micrograin Carbide (such as YG-1 X-Power) or Nanograin Carbide (such as YG-1 X5070), to achieve this result.

When milling hardened steel, should you use a wet or dry cutting method?
When milling or turning hardened steel, cutting dry (CNC milling parts is, without the use of coolant) will result in longer tool life and greater consistency. Most engineers find this to be counter intuitive, as they were taught in college that the more lubrication, the better. Hardened steel tools, such as our X5070 cutters, have coatings that are capable of withstanding temperatures CNC milling china are many times higher than those generated when cutting dry, allowing them to be used in extreme conditions.

When machining high-hardened steel, can indexable milling cutters be used successfully?
The majority of standard indexable milling grades are capable of machining materials with hardnesses up to 45 HRc without difficulty. The majority of indexable milling inserts will fail once you start machining materials with hardnesses greater than 50 HRc because they are not hard enough and have the incorrect cutting-edge geometry.

For hardened steel, a high feed milling system such as the Korloy HRM Double or HFM High Feed Milling System is the ideal indexable tool, according to the manufacturer. However, despite the fact CNC milling they mill hardened steel at high feed rates (1.2mm per revolution), these systems require only a small depth of cut (0.3-1.6mm).

This means that tools with a diameter of up to 200mm can be used to mill hardened steels!
Hardened steel tools have a negative land, shallow chip pockets, and a thick core that are common characteristics. In addition to being extremely strong, this type of geometry is also designed for high-speed machining with small depths of cut.

Once the correct tool has been selected, the next step is to determine the most appropriate tool holding technique. If you are going to the trouble of investing in high-performance milling tools, using a general-purpose tool holder may negate any benefits that the tool has to offer in the first place. Side lock arbors and ER collets are good for general milling, but they should be avoided when milling hardened steels, as they can cause damage to the steel.

Despite the fact that they may have been balanced to 15,000RPM or higher in the factory, this will not be the case once they have been assembled with a collet and tool.

Cutwel offers a variety of tool holding options for use with high-performance cutting tools for hardened steels, including the following:

Chucks with a Shrink Fit
Hardened steel machining is made easier with shrink fit chucks. With perfect concentricity and a precise 3 micron run out, shrink fit chucks are easy to maintain balance even when cutting at high cutting speeds.

Additionally, you can change tools on the machine quickly, and the clamping force increases as the tool becomes hotter! Also available in shrink chuck style geometries are the YG long neck design (with 6mm wall thickness) and the WTE HPH slim chuck (with 3mm wall thickness), both of which have a 6mm wall thickness.

The Korloy GSK collet chuck or the Cutwel HP3 slim chuck are the most versatile and cost-effective tool holders available. They outperform ER collets in almost every way, including run out of 5 microns, a slimmer nut design, and higher clamping force.

If I'm milling hardened steel, what speeds and feeds should I be running?
The ability to maintain constant chip load on the milling tool's cutting edges is critical to tool life and machining quality in milling, and particularly in high-speed milling of hardened steels.

Chip load varies widely; if the load is too low or too high, tools will either wear out too quickly, chip, or break, depending on the situation. To ensure a high-quality product, a large number of high-speed and feed cuts with small cut depths is the most effective method.