In the hardened tool steel in the high-speed cutting performance

In the mold manufacturing, the largest economic workpiece size of about 400 × 400 × 150 (length × width × height). Maximum size with high cutting speed, the relatively low material removal rate. Of course, with the machine tool dynamic characteristics and size. As mentioned earlier, most of the mold in complete cutting (single loaded card), the size is quite small. The typical procedure for the roughing to semi finishing, finishing and super finishing many cases. Always rounded and arc milling tool for later process left some margin. In many cases, to use 3-4 kinds of tools.

Usually the diameter range of 1-20 mm. In 80-90% cases, the cutting material is solid carbide end mills or ball mills. Often use a large fillet end mill. Solid carbide cutting edge tools to enhance the former angle is zero or negative (mainly used for more than 54 HRC hardness of materials). A typical and important design features is to get the maximum bending strength and thickening of the core.

Use a short length of the cutting edge and contact the ball end mill is beneficial. Another important design feature is cutting capacity, while cutting along the steep, this necessary. You can also use with indexable cutting tool size smaller. Especially for roughing and semi-finishing. These tools should be a great knife handle stability and bending rigidity. Taper shank increased rigidity, heavy metal knife handle made of stiffness also increased.

Mold should be shallow groove, not too complicated. Some trough is also suitable for use with high productivity, high-speed cutting.

Contour cutting tool to smooth the path with the better combination of milling, cutting the better.

A finishing or semi-finishing the principles to be followed is to take shallow depth of cut. Depth of cut should not exceed 0.2/0.2 mm (ae / ap). This is to prevent the holder / cutting tool produced a large bend in order to maintain a small tolerance and groove mold precision. Uniform distribution of the margin of each tool is guaranteed constant high-productivity conditions. When ae / ap constant, the cutting speed and feed rate should always be maintained at a high level. Thus, mechanical changes and the load on the cutting edge will be smaller, tool life also increased.

Cutting parameters

TiC, N, or TiAlN coated solid carbide end mills in hardened steel (HRC 54-58) on a typical cutting parameters: (HRC 54-58)

Roughing

The actual cutting speed vc: 100 m / min, ap (axial cutting speed): tool diameter 6-8%, ae (radial depth of cut): tool diameter 35-40%, fz (feed per tooth) :0.05-0 .1 mm / tooth

Semi-finishing

The actual cutting speed vc :150-200 m / min, ap (axial cutting speed): tool diameter 3-4%, ae (radial depth of cut): tool diameter 20-40%, fz (feed per tooth): 0.05-, 15 mm / tooth

Finishing and super finishing

The actual cutting speed vc: 200-250 m / min, ap (axial cutting speed): 0.1-0.2 mm, ae (radial depth of cut): 0.1-0.2 mm, fz (feed per tooth): 0.02-0.2 mm / tooth

Of course, these values outside the pole, overhang, application stability, tool diameter, material hardness and so on. These values are typical values and specific values of a particular application. In the discussion of high-speed cutting, sometimes you can see that the cutting speed values are very high and unrealistic.

Recommended use of compressed air or high-pressure mist of dry milling

   Practical definition of high-speed cutting

HSM is not simply the sense of high-speed cutting speed. It should be considered with specific methods and equipment for processing technology.

High speed spindle speed cutting without cutting. Many high-speed machining applications is medium speed spindle and conducted with large knives.

If the high cutting speed and high feed conditions to finish on hardened steel, cutting parameters for the conventional 4 to 6 times.

In these cases, the cutting speed vc may be the name of the tool diameter is calculated, rather than cutting the effective diameter. For example:

90 ° angle milling cutter, diameter of 6 mm. The actual cutting speed is 250 m / min spindle speed when = 13 262 r / min.

Ball milling, nominal diameter of 6 mm, axial depth of cut ap is 0.2 mm when the effective cutting diameter of 2.15 mm. The actual cutting speed is 250 m / min spindle speed when = 36 942 r / min.

In the small size of the rough to finish machining parts, finishing and super finishing of any size in parts, HSM means high productivity machining.

Part shapes become more complex, it appears more and more important high speed cutting.

Now mainly used in high speed cutting machine tool taper 40.