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Introduction: Cathodic arcs allow obtaining dense compound coatings with high deposition rates and good adhesion, making it attractive for applications that require hard and wear-resistant coatings [1]. In addition, a high negative voltage applied to the substrate can influence on the morphology and the density of the film. These effects generally lead to more compact coatings and reduce residual stresses, thus improving the adhesion [2]. PBII&D processes -combining cathodic arcs with a high voltage pulsed bias- employed to produce TiN coating on tool steels have shown to decrease residual compressive stresses while the texture increased [3]. The aim of this work was to study the influence of applying high voltage pulses to the substrate during the growth process on the residual stress and adhesion properties of Ti/TiN bilayers. The films were deposited on low-alloy steel and nitride stainless steel substrates, which are usually employed in the gas and oil industry.Materials and Methods: Ti/TiN coatings of 2 m thickness were synthesized by a Ti cathodic arc. The arc was run at a current of 100 A. The Ti interlayers were deposited in the base vacuum at 10-5 mbar, while the TiN films were obtained in a N2 atmosphere at 10-4 mbar. Nitrided AISI 316L stainless steel and hardened and tempered SAE 4140 steel were employed as substrates. The temperature of the substrates was maintained constant at 300 ºC during the growth process. Some of the samples were biased with negative pulses of 6 kV at 200 hz with 30 s duration. The morphology of the coatings was studied through optical and scanning electron microscopy (SEM). The film structure was analyzed by x-ray diffraction (XRD) in the Bragg-Brentano geometry and the residual stress was determined from grazing incidence XRD measurements [4]. The adhesion of the coatings was evaluated by means of the Rockwell-C adhesion test (150 kg load VDI3198 standard) [5] and a scratch test. Results and Discussion: Compact films with the presence of macroparticles, which are typical of cathodic arcs, were observed by SEM. In all cases the main peaks of TiN and Ti were detected by XRD. The coatings obtained on SAE 4140 showed TiN textured with preferred orientation in the (111) plane either for samples obtained with or without bias. Compressive residual stress was reduced from (-5.5 ± 0.8) GPa to (-3.8 ± 0.4) GPa when high voltage pulses were applied. The films deposited on nitrided AISI 316L did not exhibit apparent texture. The residual stress was determined in (-6.5 ± 0.9) GPa for both deposition processes. However, the adhesion to the substrate was clearly improved for the samples obtained by PBII&D, as can be noticed from the Rockwell-C imprints shown in Figure 1.Conclusion: Although the behavior of the residual stresses with respect to the applied bias depended on the substrate material, the adhesion was improved with the use of high voltage pulses for both studied steels.