Increasing superficial hardening in materials used in aeronautics or biomedicine

Researchers at the Public University of Navarre and the Navarre Industry Association research centre have managed to increase by 30 to 500 % the superficial hardness and resistance to wear of metals and V5Ti alloys by means of applying nitrogen. These results could be of great use for different industrial applications in which these types of materials are employed such as in the aeronautic and biomedical sectors.

Economic losses

The wear and tear of tools and machine tools is one of industry’s main problems when trying to reduce energy consumption and atmospheric contamination. The problem gives rise to important economic losses.

This fact has fed the growing demand for new, so-called second-generation materials, where optimisation of the surface properties of the material is sought without altering the properties of the volume of the material. This involves working with materials that have enhanced tribological characteristics (low friction coefficient, hardness, resistance to wear and to oxidation).

With this in mind, techniques involving ionic implantation have been shown to be a highly efficacious tool in this enhancement of surface properties. These techniques consist of ionising the atoms of nitrogen so that, after accelerating them, cause them to hit the surface we wish to modify. When these nitrogen ions enter the material surface, a number of effects are produced; amongst which are chemical reactions which drastically change the properties of the surface, such as resistance to wear and the coefficient friction.

University-enterprise co-operation

The work was carried out at the Navarre Industry Association’s installations – the Centre for the Advanced Engineering of Surfaces.

This co-operation has enabled the research results to be applied in real time in those business companies that are members of the Navarre Industry Association, particularly in those sectors involving energy generation and biomedical applications.

With this we can draw the conclusion that the techniques of ionic implantation are a highly efficacious tool in this enhancement of surface properties of tools and machine tools. Not only on steel and titanium alloy surfaces, but also with other kinds of metal such as vanadium or vanadium 5 – titanium.