Influence of nitrogen content on microstructure and the mechanical properties of nanoscale CrAlN coatings

2^nd International Conference and Exhibition on Materials Science & Engineering

October 07-09, 2013 Hampton Inn Tropicana, Las Vegas, NV, USA

Bejarano Gaitan Gilberto

Accepted Abstracts: J Material Sci

Abstract :

The first generation binary coatings as TiN, CrN, ZrN, WN, among other, have been widely used for improving the wear resistance of cutting tools and various machinery parts. However, the increase in productivity in the manufacturing process requires tools and machines that can operate at much more severe working conditions, in which binary coatings no longer meet these requirements. An alternative is the use of ternary and quaternary coatings, which have higher hardness and wear resistance. In this work a coating of chromium aluminum nitride (CrAlN) with nanoscale structure and applied on H13 steel samples was development using the plasma assisted unbalanced magnetron sputtering technique and varying the nitrogen content between 22 and 41%. The influence of nitrogen content on the microstructure, composition and existing phases as well as on the mechanical and tribological properties of the coatings was evaluated. To this purpose scanning electron microscopy, energy dispersive X-ray spectroscopy, micro Raman spectroscopy, X-ray diffraction, atomic force microscopy and nanoindentation measurements were carried out. Wear resistance was measured by a tribometer using the ball-on-disc method. The sample coated with CrAlN and a nitrogen content of 16% showed the best mechanical and tribological properties whit increased wear resistance 4 times greater that the uncoated steel sample, which opens a potential application for cutting and forming tools, as well as for machine parts subjected to wear conditions.

Biography :

Bejarano Gaitan Gilberto received his engineering degree in Metallurgy and Materials Science in 1992 at the Technical University of Aachen (RWTH- Aachen), Germany and has completed his Ph.D. at the age of 42 years from Universidad del Valle, Cali-Colombia. He made postdoctoral at the Dortmund University of Technology in Dortmund, Germany. He is an Associate Professor at the University of Antioquia from the year 2007, belongs to the Centre for Innovation, Research and Development of Materials CIDEMAT, and directs the research area for surface engineering and coatings