Heat-Resistant Coating For Cutting Tools

Nitride hard coatings made from titanium aluminum nitride (TiAlN) protect drill bits, milling cutters and indexable cutting inserts against premature failure due to wear. Now, small quantities of tantalum improve the thermal stability of these adherent layers still further.

TiAlN coatings are often doped with other elements to optimize the properties for a specific application. Thus, for instance, tantalum makes cutting operations even easier at high temperatures. Particularly when machining extremely hard materials, the tools are quickly liable to overheat. Wear-protection coatings made from titanium aluminum tantalum nitride offer even better high-temperature stability and resistance to oxidation. This makes machining operations possible at temperatures of up to 950 °C.

The Institute of Materials Science and Technology at the Vienna University of Technology conducted a detailed investigation of the properties of titanium aluminum tantalum nitride coatings. The research team carried out trials with coatings made from titanium, aluminum and tantalum in different compositions. The greatest thermal stability was achieved in the trials with a specific composition of materials (Ti_0.32 Al_0.6 Ta_0.08N). The powder metallurgy technology used at Plansee to produce the necessary targets makes it possible to manufacture products with this precise composition of materials. Plansee thus provides the ideal materials for thin films with an extremely long life.

Read the detailed research findings in the paper "Origin of high temperature oxidation resistance of Ti–Al–Ta–N coatings"
Download: http://www.sciencedirect.com/science/article/pii/S0257897214002072