Application of CrAlN coatings on carbide substrates in routing of MDF

Abstract

This study deals with the development of Chromium Aluminium Nitride (CrAlN) hard coatings (by varying the nitrogen content in the plasma, the target bias voltage, the working pressure and the deposition time) and their characterization by physical and mechanical techniques (XRD, nanoindentation, Young’s modulus, stress, scratch-test, composition, etc.) in order to determine the optimal deposition conditions to apply the coatings to carbide substrates. Moreover, in order to improve the adhesion of the same optimal hard coatings and as it was efficient with Diamond Like Carbon (DLC) coatings, we tried to modify the carbide inserts by chemical attacks with Murakami’s agent before machining. The coated tools (with and without Murakami’s attack) were then tested in routing of Medium Density Fibreboard (MDF). A comparison of the abrasion and shock resistance of the conventional tools with the treated ones, was made. The efficiency of Murakami’s agent was also studied. It was obvious that the coated carbide tools had greater tool life than the untreated ones. Besides, Murakami’s attack was not optimized or not a solution to improve the adhesion of nitride coatings on carbide inserts.