Indexable insert
Indexable inserts are made of hard metal , cermet , polycrystalline cubic boron nitride (CBN), polycrystalline diamond (PCD) or cutting ceramics or, more rarely, of HSS or HSSE / HSS-PM and serve as a cutting material carrier for cutting metals, plastics or wood, for example.
They are manufactured using the sintering process and can be screwed or clamped into tool holders (e.g. turning tools or milling cutters ) (see also: differential thread for screw connection principle ). Indexable inserts usually have several cutting edges . To improve the properties, indexable inserts are often coated with hard materials such as titanium carbide (TiC) or titanium nitride (TiN) in order to improve wear resistance and heat resistance. Indexable inserts are available in different shapes and sizes so that they can be used for specific applications.
We speak of positive cutting inserts when the cutting insert itself has a clearance angle > 0 ° (see Figure 3 - coated cutting insert). Negative cutting inserts themselves have a clearance angle of 0 °. The clearance angle required for machining is created by the specific installation of the cutting insert in the tool holder (e.g. drill , milling cutter). The advantage of negative cutting inserts can be seen both in the more stable cutting edge, so that these cutting inserts can be found especially in difficult machining, and in the fact that there are twice the number of possible cutting edges in contrast to a positive cutting insert.
To protect against rapid wear and tear and to increase the service life, the cutting edge is provided with a radius that is between 0.1 mm and 1.6 mm in the production area. If a cutting edge wears and is blunt, the insert is simply turned, for positive and negative inserts, or turned, for negative inserts. Indexable inserts almost always have chip breakers in order to achieve short-breaking chips during machining . There are different standards in which indexable inserts are described in different variations. DIN ISO 1832 provides an overview of the designations on the indexable insert and the possible geometric shapes.
See also
- Lathe Tool - With section for indexable inserts for turning
