Coating tools is one of the most important ways to improve tool performance. The emergence of coated tools has led to a major breakthrough in tool cutting performance. Coated tool is in the toughness of the better cutter body, coated with one or more layers of good wear resistance of refractory compounds, it will be the tool matrix and hard coating combination, so that the tool performance is greatly improved. Coated tools can improve machining efficiency, improve machining accuracy, extend tool life, reduce processing costs.
New CNC machine tools used in cutting tools, about 80% of the use of coated tools. Coated tools will be the most important tool varieties in the field of CNC machining in the future.

The performance characteristics of coated tools are as follows:

　　①Good mechanics and cutting performance: coated tools combine the excellent properties of the base material and the coating material, which not only maintains the good toughness and high strength of the base, but also has the high hardness, high wear resistance and low coefficient of friction of the coating. As a result, the cutting speed of coated tools can be increased by more than two times than uncoated tools, and a higher feed is allowed. The life of coated tools is also improved.

　　② Strong versatility: coated tool versatility is wide, the machining range is significantly expanded, a coated tool can be used instead of several kinds of non-coated tools.

　　③ coating thickness: with the increase in coating thickness tool life will also increase, but when the coating thickness reaches saturation, tool life is no longer significantly increased. When the coating is too thick, it is easy to cause stripping; when the coating is too thin, the wear resistance is poor.

　　Re-abrasion: poor re-abrasion of coated blades, complex coating equipment, high process requirements, long coating time.

　　⑤ Coating material: cutting performance of tools with different coating materials is not the same. For example: when cutting at low speed, TiC coating has the advantage; when cutting at high speed, TiN coating is more suitable. More suitable.

Application of coated tools

　　Coated tools have great potential in the field of CNC machining, will be the most important tool varieties in the field of CNC machining in the future. Coating technology has been applied to end mills, reamers, drills, composite hole processing tools, gear hob, gear shaper, shaving cutter, shaping broach and a variety of clamping indexable inserts to meet the high-speed cutting and processing of a variety of steel and cast iron, heat-resistant alloys and non-ferrous metals and other materials.