Titanium Nitride Coating on AISI 1010 and AISI M2 steels by Thermo-Reactive deposition tecnique

TITANIUM NITRIDE COATING ON AISI 1010 AND AISI M2 STEELS BY THERMO REACTIVE DEPOSITION TECNIQUE SUMMARY Keywords: Wear, Corrosion, Titanium nitride coating, Thermo-reactive deposition coating, Chemical vapor deposition, Physical vapor deposition. Service life of the machine parts and tools are limited by wear and corrosion in the service conditions. For this reasons, the protection of these materials in the corrosive environment and wear conditions is of major importance, especially for economic reasons. To solve there problems and having more service life, new tool steels with high alloying elements are produced and yet. Instead of changing the tools with new and expensive materials, it is economical to directly solve the problems, that is, changing the surface characteristics of the used materials for improving the corrosion resistance and wear resistance. For these reasons, hard coating technologies have had a great importance in the tool industry. Hard ceramic films can be produced by different coating techniques. Chemical vapor deposition (CVD) and physical vapor deposition (PVD) techniques have the most important techniques. In this process, coating systems are expensive and know-how is needed for the coating parameters. Because of these, thermo-reactive deposition technique has a major importance due to advantages like; no expensive equipment, no restriction on the dimensions of the coated materials, etc. In this study, titanium nitride coating by thermo reactive deposition technique has been studied. The main goal of this study is to produce titanium nitride coating on the surface of AISI 1010 and AISI M2 steels and investigate mechanical and structural properties of these coating layers. This study includes two steps. First one is nitriding the coated steel because of the formation of nitride base coating on the steel substrate. Second one is the titanising of the pre-nitrided steel substrate to form titanium nitride layer on the pre-nitrided steel substrate. Titanising treatment was carried out at 900°C, 1000° and 1 100°C for 1-4 hours on the nitrided steel at 575 °C for 2h. Titanising treatment was employed in the powder mixture consisting of ferro-titanium, alumina and ammonium chloride. Surface characteristics and phase analysis of titanium nitride coated steels were carried out by optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction (XRD) analysis. The hardness of the coating layers are measured by micro-vickers indenter. As a result, titanium nitride coating on the steel substrates was carried out by means of thermo reactive deposition technique. Titanium nitride layer formed on the steel substrates are extremely hard (1850-2200 HV), dense, smooth, porosity free and of good apperence. xxvu