Magnetron sputtering is a flexible technique and allows producing a significant amount of types of coatings, thus, this method was also used within the frame of this paper in order to obtain dark Ti(CON) coatings. The films, with various compositions, were deposited onto high speed steel (AISI M2) substrates, in a closed field unbalanced reactive d.c. magnetron sputtering system, using a reactive atmosphere composed of acetylene (C source) and a mixture composed of oxygen and nitrogen. The deposition parameters were chosen as a junction of pre-existing knowledge about sputtered Ti-O-N and Ti-C-O films, varying the flow ratio C2H2/(O2+N2). Mechanical properties of the films, namely microhardness and Young's modulus were determined using loading and unloading curves data, obtained with an instrumented nanoindentation equipment using a Berkovitch tip.

Within the frame of this work super-hard nanocomposite thin films were deposited using a more recently developed deposition method, namely the magnetron sputtering using a high power generator (HIPIMS) connected to the Ti target and a classical DC pulsed generator connected to the Si target. The films were co-spultered from two metallic targets of Ti and Si (99,99% purity). The silicon content was varied by controlling the DC intensity applied on the silicon target, while HIPIMS discharge parameters were kept constant on the titanium target, The Si enrichment was made by the variation of Si target's intensity between 0.2A and 0.4A. The coatings morphology was observed on brittle-fracture cross sections by scanning electron microscope (SEM). Structure of the layers was achieved via X-Ray Diffraction (XRD). The dynamic friction coefficient and wear rate values (abrasion wear) were estimated using a pin-on-disk tribosystem.

In the present paper, we have carried out the simulation of the heat treatment process, under optimum conditions, of a sample made from C70W2 tool steel with the aid of specialized software. After sketching the sample geometry (cylinder with the dimensions H 12 and D 25), the mesh has been generated, followed by the setting of the subdomain and boundary conditions and the solving of the model by using a suitable solver. The advantage of the simulation of heat treatments for the case of tool steels is determined by the fact that one can visualize, at any computed moment, specific elements of the studied process: temperatures, metallurgical phases, grain sizes, residual stresses, making it easier to detect defects early in practical usage settings.

Ti-Si-C thin-films were prepared by d.c.reactive magneron sputtered on (AISIS M2) steel sample, at 200 degrees C. The depositions were carried out from Ti targets, one with some Si and the other with C pieces incrusted in the erosion zone, working in a simultaneously mode, under the variation of d.c. power applied to the targets. During the deposition process, all the samples were based with a bias voltage of -70V. The atomic composition of a deposited samples was measured by electron probe microanalsis (EPMA) in a Cameca SX-50 apparatus. A tribological characterization for the prepared thin-filims has been done, taking into account the differen measurement of roughness, static friction coefficient and wear. The results revealed that there is no clear correlation between the tribological paramenters, and the general wear behaviour could be explained considering the films composition. Thus, the best results were registered for C/Si ratio (at.%) between 2.2- 5.2, corresponding to a current ration I-Tic/I-TiSi(A) between 1.4-2.9.

As a result of technological progress in recent years, a new challenge was passed onto decorative hard coatings. While enhancing the appearance and lending attractive coloration to surfaces, the films are supposed to provide scratch resistance, protection against corrosion and durability. For this work, TiN(O) and TiN(C,O) thin films were prepared. Within the TiN(O) system, film colours varied from the glossy golden type for low oxygen contents to dark blue for higher oxygen contents. In order to reach darker colours (black), TiN(C,O) thin films were deposited, and results revealed the possibility to deposit very dark black films. All these results have been analysed and are presented as a function of both the deposition parameters and the particular composition and crystalline phases present in the films.

The main purpose of this work consists in the preparation of titanium oxycarbide, TiCxOy, thin films, in which the presence of oxygen changed the film properties between those of titanium carbide and those of titanium oxide. Varying the oxide/carbide ratio allowed to tune the structure of the films between titanium oxide and carbide and consequently electronic, mechanical and optical properties of the films. The depositions were carried out from a TiC target by direct current, dc, reactive magnetron sputtering, varying the oxygen flow rate. The obtained results showed that the film's properties can be divided into 3 different regimes — i) carbide, ii) a transition zone and iii) an oxide one. X-ray diffraction results revealed the occurrence of a face-centered cubic phase (TiC-type) for low oxygen content, also obtained in the TiC1.6(O) film, with a clear tendency towards amorphization with the increase of the oxygen flow rate. For the highest oxygen contents, the results revealed the development of a mixture of poorly crystallized TiO2 phases. The colour results indicated a strong dependence on the O/Ti ratio. A progressive reduction of hardness and residual stresses with the increase of the O/Ti ratio was also observed. The residual stresses, as well as the film structure, seem to play an important role on the adhesion of the coatings. The static friction coefficient revealed also some correlation with the mechanical properties, but mainly with the surface roughness.

Within the frame of this work TiCO d.c. reactive magnetron sputtered films were prepared on (AISI M2) steel samples at 200°C. The depositions were carried out from a TiC solid target under the variation of two process parameters, such us time deposition and flow rate of reactive gas O 2 . The O 2 flow varied between 0.5 and 7.5 sccm and the deposition time between 3600 and 6000 s. Static friction coefficient, wear and residual stresses are characterized and discussed as a function of both process parameters (oxygen flow and time). A compressive residual stress state has been observed if the O 2 flow is bigger than 1 seem. Generally, the addition of oxygen till 7.5 sccm leads to an increasing of this compressive stress level to -17.7 GPa. At the same time, for an oxygen flow rate higher than 2 sccm and a high compressive residual stress level, the deposited films presented good wear behaviour.