Why use CBN tools?
First of all, CBN cutting tools were synthesized by artificial methods under high temperature and high pressure in the 1950s. Its hardness is second only to diamond but much higher than other materials. Therefore, cubic boron nitride and diamond are collectively called superhard materials. It has high temperature red hardness, good wear resistance, strong impact toughness, and good thermal stability. The first CBN tools used in the machinery manufacturing industry are mainly welded, mainly used for finishing processes, with a small depth of penetration. Later, with the needs of the manufacturing industry, the CBN tool industry has developed integral CBN tools that can cut large margins and strong interrupted cutting, and more economical embedded CBN tools with multiple cutting edges.
What circumstances is it better to choose CBN tools for machining workpieces?
CBN tools are suitable for processing fields. Due to the performance of CBN tools, they are more suitable for processing high-hardness and difficult-to-machine materials, such as high-hardness cast iron/cast steel, heat-treated high-hard steel parts, powder metallurgy, high-temperature alloys and other materials. With the efficient development of the industry and manufacturing industry, CBN tools are also widely used in the field of ordinary gray cast iron, and the processing effect is not only high in efficiency, but also low in cost.
For steel parts after heat treatment, the CBN tool with a hardness above HRC45 is better. If the hardness is lower than HRC45, it is easy to stick to the tool during processing. It is more suitable to choose cemented carbide tools or coated tools.
1. Intermittent cutting of hardened parts with hardness above HRC45. Intermittent cutting does not know if you know. The so-called intermittent cutting means that there are holes or key grooves on the machined surface, and the tool machining process is interrupted. In view of this kind of situation, it is better to choose CBN tool to process. CBN tools have both impact toughness and fracture resistance, and there will be no chipping or chipping.
2. For processing high-hardness cast iron/cast steel parts formed by casting, especially for workpieces with casting defects such as sand inclusions and air holes, the CBN tool has a better processing effect.
3. It is better to choose CBN tools when producing gray cast iron parts in large quantities.
4. CBN tools are suitable for dry cutting and are environmentally friendly. CBN tool material has a certain degree of brittleness, especially the overall polycrystalline CBN tool, which is easy to break when cutting fluid is added during the machining process; CBN tool has strong red hardness at high temperature. The so-called high temperature red hardness refers to normal cutting under high temperature (1300℃). Machining not only does not require chip flutes, but also ensures stable tool life.