The main cutting edge of the end mill is on the cylindrical surface, and the cutting edge on the end face is the secondary cutting edge. When working, the feed motion cannot be made along the axial direction of the milling cutter. End mills can be used in machining fields such as side machining, groove machining, and curved surface machining. There are also a wide variety of end mills that can be used for various machining forms.
In the past, high-speed steel integral end mills were commonly used, but now with the advancement of coating technology and tool material technology, coated carbide solid end mills and indexable end mills are gradually popularized and widely used in mold processing, High hardness material processing and other fields.
1. The name of each part of the end mill:
Helix angle: The larger the helix angle of the end mill, the longer the contact line between the workpiece and the cutting edge, the smaller the load applied to the cutting edge per unit length, which is beneficial to prolong the tool life. But on the other hand, as the helix angle increases, the axial component force of the cutting resistance also increases, making the tool easy to fall off from the handle. Therefore, when machining with a tool with a large helix angle, the rigidity of the tool handle is required. The 0° helix angle is called a straight edge, and its contact line is the shortest.
Selection of helix angle: Stainless steel is a difficult-to-cut material with low thermal conductivity, which has a great impact on the tool tip. Using an end mill with a large helix angle is beneficial to prolong the tool life. As the hardness increases, the cutting resistance of high-hardness materials increases, so end mills with large helix angles should be selected. For thin plate processing and other situations where the rigidity of the workpiece is low, an end mill with a small helix angle should be used.
Core thickness: Core thickness is an important factor in determining the rigidity and chip flute of an end mill. The core thickness of solid end mills is generally 60% of the outer diameter. As the core thickness increases, the cross-sectional area increases and the rigidity increases, but the chip pocket decreases and the chip removal performance deteriorates; on the contrary, the core thickness decreases and the rigidity decreases, but the chip removal performance increases.
Helical direction of chip flute
2. The number of edges of commonly used end mills
3. Types and shapes of end mills
The types and shapes of end mills can be classified according to peripheral edge, bottom edge, shank and neck. Different types have different shapes and characteristics, and their application conditions are also different.
1) Types, shapes and characteristics of peripheral blades
2) The type, shape and characteristics of the bottom edge
3) Types, shapes and characteristics of handle and neck
When the end mill is rotating, the midpoint of the bottom edge is relatively stationary, and it does not have any cutting and chip removal properties, so it cannot be cut vertically.
