Hipims TiB2 Coating in Titanium Alloy Cutting Tools

TiB2 (titanium diboride) coating #

Nasi TiB2 (titanium diboride) coating, 3000HV hardness, prepared by HiPiMS, low stress and high chipping resistance. Especially suitable for non-ferrous metals (such as aluminum, copper, magnesium and its alloys) processing in the wear-resistant and anti-metal high-temperature corrosion working conditions. And can realize 300 m/min high speed cutting.

TiB₂ has a hexagonal crystal system structure, the contact angle with liquid aluminum, copper and other metals are more than 90 °, at 1000 ℃ still maintains the hardness of 3.6 GPa. TiB₂ coated tool friction coefficient compared with the traditional cemented carbide reduced by more than 40%.

01 Characteristics of Titanium Alloy Machining #

• Small density, poor thermal conductivity, cutting heat is not easy to diffuse when cutting, concentrated in a small area near the cutting edge, resulting in a very short tool life.
• Titanium alloys have a high affinity; they are highly chemically active and tend to affinity with metals in contact with each other, leading to bonding, increased diffusion, and tool wear.
• The low modulus of elasticity and high elastic deformation of titanium alloy will cause the machined surface to have a large contact area with the back cutter surface, which will cause severe wear.
• Titanium alloy cutting deformation coefficient is small, so that the chip in the front face of the sliding friction distance increases, accelerating tool wear.

Titanium alloy material machining process cutting force, high temperature, resulting in rapid tool wear, machining process time-variant enhancement, although to ensure that the size and form accuracy of the components to meet the design requirements, but the surface of the workpiece will appear machining cutter marks, prismatic damage, surface microcracks, machining hardening, tissue damage and other surface integrity issues.

02 Titanium Alloy Processing Pain Points #

03 Role of PVD coatings on CNC tools #

Enhance tool surface hardness and improve tool wear resistance; thermal insulation or thermal conductivity; lubrication and easy chip removal.

Also, side effects, yes PVD coatings are likely to have side effects on the tool, reducing cutting ability. When the material used for PVD does not match the working conditions of the machining, even at micron thickness, the effect on the edge is huge. In addition, usually tool coatings are coated at high temperatures to increase adhesion, which also has a significant detrimental effect on the sharp edge.

TiB2 coatings prepared by Hipims coating equipment have obvious advantages #

The processed material is Ti6Al4V titanium alloy, which is commonly used in the market, and the TiB2 coating is prepared by DCMS and Hipims in the same PVD device, and relevant cutting tests are conducted. To compare the performance difference between TiB2 coatings prepared by DCMS and Hipims in parallel.

summarize #

TiB2 coatings are prepared using Hipims technology, which is characterized by high dissociation rate, high energy, dense prepared coatings, low stress, and less prone to chipping. At the same time TiB2 coating tool surface oxidation produced by the B2O3 liquefied film, play a self-lubricating effect, reduce sticky sticky. With a small amount of wear, it can effectively extend the service life of titanium alloy cutting tools.

Related links #

TiB₂ coatings for non-ferrous metal processing applications