How to deal with difficult processing materials?

How to deal with difficult processing materials?

This is because it relatively poor machinability,such as: high hardness and high strength, high plasticity and high toughness, low thermal conductivity, low plasticity, high brittleness, and too active chemical properties, the cutting force is high during cutting and the cutting temperature is high. Chips are difficult to control, work hardening and tool durability are low.

Using new materials

Although the hardness of cubic boron nitride cutter is slightly lower than that of diamond, it is much higher than other high hardness materials, and its thermal stability is much higher than that of diamond, which can reach above 1200 °C, suitable for high temperature dry cutting. Another advantage is that it is chemically inert.

The performance of high-speed steel cutters is not advanced enough. On the base of high-speed steel, a thin layer of wear-resistant material (usually TiN) is coated by physical vapor deposition (PVD) method, which can significantly improve tool life and surface quality, and reduce cutting force.
Carbide tools are powder metallurgy products of carbides (WC, TiC, etc.). According to the size of the crystal grains, it can be divided into ordinary hard alloy, fine-grained hard alloy and ultra-fine grained hard alloy; it can be divided into tungsten-cobalt (YG), tungsten-cobalt-titanium (YT) and added according to chemical composition. Rare carbides (YW). Tungsten-cobalt-titanium (YT) tools have a strong affinity with titanium alloys.

Diamond tools have the advantages of extremely high hardness and wear resistance, sharp edge, low friction coefficient, high modulus of elasticity, high thermal conductivity and low affinity with non-ferrous metals. Diamond tools are suitable for finishing and super finishing of difficult-to-machine materials. The heat resistance temperature of diamond is only 700~800 °C, and it must be fully cooled and lubricated during processing.

The ceramic tool material is obtained by separately adding carbides, nitrides, borides, oxides, and the like to the alumina and silicon nitride substrates. Ceramic tools have higher temperature performance than hard alloys and are therefore suitable for high speed cutting. The fracture toughness and thermal shock resistance of Si3N4 based ceramic tools are higher than those of Al2O3 based ceramic tools, which are suitable for high speed cutting of cast iron.