• Wierzchoń, Tadeusz
• Sobiecki, Jerzy Robert
• Mańkowski, Patrycjusz

Abstract

<p>A gaseous mixture composed of tetraisopropoxytitanium, nitrogen and hydrogen in the PACVD process, has been used to obtain Ti(NCO) layers of good performance properties, such as a high hardness and good resistance to corrosion and to frictional wear. The temperature of the process is 500°C. The paper describes a method which permits improving the properties of the Ti(NCO) type and composite nitrided+Ti(NCO) type layers by plasma nitriding treatment. The structure of the layers is described and their wear and corrosion resistance is determined. The results of SEM examinations, microhardness and stereological measurements and X-ray diffraction analysis are discussed. The TiO, TiC and TiN phases have the same crystallographic structure of the NaCl type. The Ti(NCO) layer is a solid solution of these phases with nitrogen atoms in the TiN lattice being replaced by carbon and oxygen atoms. The lattice parameter is strongly related to the chemical composition of the layers. As the nitrogen content increases and oxygen content decreases the lattice parameter can increase to 0.424nm a value characteristic of pure stoichiometric titanium nitride. The nitrogen content can be increased by reducing the process temperature to 500°C, by using pre-nitrided substrates and by subjecting the Ti(NCO) layers obtained to nitrogen plasma annealing. © 2002 Elsevier Science Ltd. All rights reserved.</p>

Topics

• impedance spectroscopy
• Carbon
• corrosion
• phase
• scanning electron microscopy
• x-ray diffraction
• Oxygen
• Nitrogen
• nitride
• composite
• hardness
• Hydrogen
• titanium
• annealing
• tin
• oxygen content