Effect of the deposition and thickness parameters of titanium nitride (TiN) coatings on the fatigue strength

Abstract

669.15:539.43 The effect of vacuum-plasma coatings of titanium nitride (TiN) on the fatigue strength of titanium VT1-0 is investigated in terms of the coating deposition and thickness parameters. The analysis of the obtained results is performed with the goal of improving the required fatigue strength of the base material-coating composition. It is shown that in all the investigated cases, TiN coatings enhance the fatigue strength. The optimum range of coating thicknesses is established, in which the change in the deposition conditions influences slightly the fatigue limit. A satisfactory agreement is noted between the experimental and calculated values of fatigue limits obtained using the calculation model earlier proposed by the authors. The principal possibility of essential increasing the fatigue strength has been discussed and confirmed in the case of formation of ultra-thin coatings under well-defined conditions of their deposition.Introduction. Surface hardening of engineering components through the use of vacuum plasma coatings has a number of economic, ecological and manufacturing advantages. These coatings obtained by the physical vapor deposition (PVD) method combined with the ion bombardment-assisted deposition (IBAD) during the condensation of the metal plasma are applied to components using an industrially produced "Bulat"-type deposition system [1]. When producing vacuum plasma coatings with the use of this type of equipment, it is possible to easily vary the parameters of the manufacturing process, such as medium pressure, arc current intensity, gas (N, O 2 , Ar, etc.) supply time, composition of the gas atmosphere, deposition rate, and temperature, which offers a real possibility of optimizing the process for producing coatings with different properties, in particular, the strength properties.In this paper, the influence of vacuum plasma coatings of titanium nitride (TiN) on the fatigue resistance of titanium VT1-0 is investigated in terms of the deposition and coating thickness parameters. The analysis of the results obtained is performed based on the statement of the problem and objectives of the investigation.Problem Statement. Real processes accompanying the formation of coatings are of a complex nature. Depending on the energy-based parameters of the coating deposition process, these may influence the change in the chemical-structural composition and its related physico-mechanical characteristics. Thus, aside from the titanium δ-nitride TiN, coatings of TiN can contain a certain amount of α-Ti and titanium ε-nitride (Ti 2 N) to form solid

Resistance of PVD Coatings to Erosive and Wear Processes: A Review

“…Hence, erosion resistant materials should be resistant to the mentioned damage processes [29,30]. Most of the investigations prove that deposition of PVD coatings improve fatigue resistance [31][32][33][34][35][36][37][38][39][40][41][42]. However, according to References [35,39,41,43], deposition of PVD coating may also decrease fatigue resistance or has no effect on fatigue resistance [36,42] in comparison to that of substrate material.…”

“…Most of the investigations prove that deposition of PVD coatings improve fatigue resistance [31][32][33][34][35][36][37][38][39][40][41][42]. However, according to References [35,39,41,43], deposition of PVD coating may also decrease fatigue resistance or has no effect on fatigue resistance [36,42] in comparison to that of substrate material. The improvement of fatigue resistance of the material by deposition of PVD coatings depends on the following factors: coatings properties, substrate properties and test conditions.…”

“…In case of fatigue, very important are such test conditions as frequency and a load ratio, R. In case of tests performed with R = −1, deposition of PVD coatings leads to improvement of fatigue endurance in most cases [31,36,38,44], while in case of R = 0.1, the fatigue endurance depends on the coating thickness and material of the coating [45]. With increasing thickness of PVD coating, the fatigue resistance decreases [36,41,45]. However, the results of fatigue tests also depend on the substrate material.…”

“…Because the material property that has largest impact on resistance to cavitation erosion, solid particle erosion and wear is hardness [50,51], hard coatings are tested as anti-erosion and anti-wear coatings [52][53][54][55]. In the case of PVD coatings, the properties affecting their resistance to erosion depend on such factors as the technique and parameters of deposition [40,41,43], the coatings Coatings 2020, 10, 921 3 of 34 thickness [38,41,45,[56][57][58], the type of PVD coating (monolayer or multilayer coating) [21,33,36,[59][60][61][62][63] and the substrate properties [64]. Since PVD coatings play an increasingly important role in various applications and there are many different opinions regarding their resistance and the relationship between their properties and resistance to the above-mentioned deterioration processes, the aim of the article is to present the recent knowledge on the resistance of PVD coatings to these types of degradation, discussing the impact of the properties and structures of coatings on this resistance, and presenting common relationships between coating properties and resistance to the mentioned degradation processes.…”

Wrinkled titanium nitride nanocomposite for robust bendable electrodes

“…The synthesis temperature T S was limited to 150 °C to avoid PET alteration. For T S =100 °C, σ th was estimated to be about −0.6 GPa, using the Poisson coefficient ν=0.25 and 0.35 (ppm) , the young modulus E=400 and 3 (GPa), the CTE α=6× 10 −6 (K −1 ) and 35×10 −6 for TiN and PET respectively [26,27].…”