In general, a decorative function of hard protective coatings is not important for the performance of the tool, the color of coating provides several advantages: (1) in the machining process, color of the tool indicates its wear; (2) it can be used to distinguish between the tools; (3) it has an aesthetic appearance and can be a recognizable brand for the tool manufacturer. We developed a protective/decorative coating in an industrialscale deposition system using standard hard coating materials. Color of the coating was obtained using the interference effect between the top layer of nanolayered AlTiN coating and reflective layer. Since AlTiN is a semitransparent material in visible range it does not cause significant shift in color with the angle of view and the color has a metallic appearance. In this way intense colors of blue, violet and green were produced by precisely controlling the thickness of the top layer – for this purpose a previously developed simulation of coating growth was used. Coatings were prepared on cutting tools of different geometries but can be applied to any application where decorative and protective functionality is required. We were awarded a patent for this innovation.
B.04 Guest lecture
COBISS.SI-ID: 24447271In general, a decorative function of hard protective coatings is not important for the performance of the tool, the color of coating provides several advantages: (1) in the machining process, color of the tool indicates its wear; (2) it can be used to distinguish between the tools; (3) it has an aesthetic appearance and can be a recognizable brand for the tool manufacturer. We developed a protective/decorative coating in an industrialscale deposition system using standard hard coating materials. Color of the coating was obtained using the interference effect between the top layer of nanolayered AlTiN coating and reflective layer. Since AlTiN is a semitransparent material in visible range it does not cause significant shift in color with the angle of view and the color has a metallic appearance. In this way intense colors of blue, violet and green were produced by precisely controlling the thickness of the top layer – for this purpose a previously developed simulation of coating growth was used. Coatings were prepared on cutting tools of different geometries but can be applied to any application where decorative and protective functionality is required. We were awarded a patent for this innovation.
B.04 Guest lecture
COBISS.SI-ID: 27320615The electrochemical process named anodic oxidation of Al-alloy results in the growth of a porous aluminum oxide on the surface of an Al-alloy. In the first instance the resulting oxide layer serves to protect the alloy. Furthermore, the oxide layer can be colored with the desired color by the addition of certain colors. The aim of our work was the optimization of key parameters, which are a prerequisite for successful anodic oxidation of Al-alloys. Al-alloys were mechanically polished and afterwards the parameters for successful anodization were optimized, such as: applied voltage and time of anodization, concentration and temperature of the electrolyte, etc. by optimizing these parameters we can regulate the pore diameters, the distance between pores and ultimately the thickness of the Al2O3 layer on Al-alloy. After the anodization we focused on optimization of the coloring of the existing Al2O3 layers using copper salts. After the adsorption of the selected color in the pores and on the surface of Al2O3, the pores must be sealed to prevent the damage of color. The sealing is conducted by using the socalled hot sealing of the pores, which results in the boehmite structure of Al2O3.
B.04 Guest lecture
COBISS.SI-ID: 27240487According to selection of scientific council of individual sciences at Slovenian Research Agency the patent N°23538 (Hard protective coatings with the ability to change their color) was selected as exceptional achivement in the year 2012. This patent was arised in the framework of this resarch project (L24249, Color, absorption and protective nanolayer coatings for aluminium alloy).
E.03 Other
COBISS.SI-ID: 27421735