Rough Trend Research Articles

Intrinsic tensile brittleness of tilted grain boundaries and its shear toughening

In the endeavors of working with microstructures in polycrystalline metals for better strength and ductility, grain boundaries (GBs) are placed at the front burner for their pivotal roles in plastic deformation. Often the mechanical properties of polycrystalline metals are governed by mutual interactions among GBs and dislocations. A thorough comprehension of GB deformation is therefore critical for the design of metals of superb performance. In this research, we investigated the mechanical behavior of symmetric tilt grain boundaries in face-centered cubic (F.C.C.) nickel, which may be subject to tension, shearing, and mixing-mode load using molecular dynamics simulations. We observed that (1) there exist four types of micro deformation mechanisms in GBs, and illustrate at the atomistic scale their distinctions and their dependence on the activation of lattice slip in the crystal; (2) GBs are intrinsically brittle under tension but exhibit ductile behavior during shearing. Shifting from pure tension with increasing shear component during mixing-mode load leads to GB toughening; and (3) there lacks conceivable dependence of GB tensile strength on tilted GBs, in contrast to a relatively rough trend of greater shear strength in GBs of large misorientation. GB energy shows no direct connection with GB strength, as broadly reported in existing literature. This research enhances our mechanistic understanding of GB plasticity in crystalline metals, and points to a potential way of making strong-yet-tough polycrystalline metals through GB engineering: in addition to GB structure manipulation, tuning the loading mode of GBs may open another avenue for their better performance.

Change in Surface Roughness on the Inner and Outer Surfaces of the Microtube during Hollow Sinking.

Hollow sinking experiments and tensile tests were conducted to clarify the evolution of surface roughness during hollow sinking. Stainless steel tubes (outer diameter: 1.5 mm; wall thickness: 0.045 mm) featuring a single grain spanning the wall thickness achieved via annealing as the starting material. The tube was drawn without an internal tool using a draw bench by controlling the tube drawing speed ratio of the die entrance and exit sides. The surface roughnesses of the inner and outer surfaces at the die entrance and exit sides of the drawn tube were compared with the surface roughnesses of the inner and outer surfaces under the uniaxial tensile deformation of the starting material. As a result, two major findings were revealed; the surface roughness formation behavior during the hollow sinking; the uniaxial tensile deformation exhibits a tube on both sides of the entrance and the exit of a die. Former uniaxial tensile deformation forms surface roughness of the tube at the die-entrance-side. However, hollow sinking reduces the roughness. The tube keeps its small roughness even though it is applied the later uniaxial tensile deformation behind the die exit. Furthermore, the conventional formula to predict the surface roughness of a metal sheet caused by the uniaxial tensile deformation can predict the surface roughness of a tube in the hollow sinking. At both die entrance and exit sides, the roughness of the inner surface was larger than that of the outer surface at the die entrance and exit side. The outer surface of the tube contacts the inside of a die when the tube passes through the die. The height of the convex parts decreased at that moment. Hollow sinking suppressed the increase in surface roughness of the inner surface as the outer surface was smoothed in the die. However, due to the formation of surface roughness after leaving the die, there is an overall increasing trend in inner surface roughness.

Enhancing triboelectrification via multiscale roughness dependent thermal dissipation

Polymer-based triboelectric nanogenerators (TENGs) have held promise due to their excellent interfacial conformity and ease of fabrication. However, the role of surface roughness in triboelectricity requires further study. In this study, we have manipulated the nano-/micro-scale roughness configuration in polydimethylsiloxane (PDMS) over a wide range of extents using various sandpaper-based templates. According to the power spectral density analysis, the spatial frequency of template-free PDMS exhibits several distinct bandwidth regions each with different fractal dimensions significantly higher than 2, despite having the lowest roughness value. In contrast, most template-based PDMS shows an entire spatial frequency region that scales nearly with a single power factor corresponding to a fractal dimension as low as 2, despite slight increases in roughness values. Consequently, the surface temperature gradient and output performance of TENG increased, following the trend of fractal dimension and roughness, but the surface potentials have remained almost invariant. However, excessive increases in the surface roughness cause the spatial frequency to be divided once again into several different bandwidth regions with different cutoffs and higher fractal dimensions. These results suggest that the performance of TENG can be controlled by tuning both surface roughness and self-affine properties over multiple scales. Specifically, adhesive interaction becomes dominant on surfaces with lower fractality, enhancing TENG performance due to the expanded contact area. This study sheds light on the relationship among triboelectricity, thermal dissipation, and topography.

Effect of composite textured rough surfaces on the lubrication performance of cylindrical roller bearings

PurposeThe purpose of this paper is to study the impact of different types of textures on the friction lubrication performance of cylindrical roller bearings.Design/methodology/approachIn the present study, the composite texture hydrodynamic lubrication model that takes into account the effects of surface roughness is established, and the Reynolds equation for the oil film is numerically solved using the finite difference method. The study investigates the oil film carrying capacity and maximum pressure of bearings under two different arrangements of four composite textures and conducts a comparative analysis of the oil film characteristics under various texture parameters and surface roughness levels.FindingsWhen the roughness of the inner texture surface and the contact surface are equal, the bearing capacity of the composite texture is intermediate between the two textures. The impact trend of surface roughness on fluid dynamic pressure effects varies with the type of composite texture; the internal roughness of the texture affects the micro-hydrodynamic pressure action. Composite textures with different depths exhibit improved bearing capacities; elliptical cylindrical parallel and elliptical hemispherical parallel textures perform better when their area densities are similar, while other types of composite textures show enhanced bearing performance as the ratio of their area densities increases.Originality/valueThis paper contributes to the theoretical investigations and analyses on designing the textured rolling bearings with high lubrication performance.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2024-0050

Titanium surface treatments and their effects on the roughness factor

The surface pretreatment of a Ti substrate to produce metal oxide electrodes with electrocatalytic properties is of fundamental importance. The preparation of the substrate prior to the application of the coating critically affects the properties of the coating, including its surface roughness, adhesion, and corrosion resistance. In this work, different treatments were applied to the surfaces of Ti discs and their effects on surface roughness were studied. The treatments applied to Ti consisted of three stages: (1) mechanical treatment, (2) degreasing, and (3) chemical treatment. The first stage was carried out with 120 grit SiC abrasive sandpaper, the second stage was carried out with acetone (group A) or sodium hydroxide (NaOH) solution (group B), and the third stage was conducted using hydrochloric acid (HCl), oxalic acid, a mixture of hydrofluoric acid (HF)/phosphoric acid (H3PO4), or a sequence of all three chemical treatments (i.e., HCl, oxalic acid, and HF/H3PO4). The morphological properties, surface composition, and electrochemical behavior of the treated Ti discs were characterized by scanning electron microscopy (SEM), X-ray diffractometry (XRD) and cyclic voltammetry (CV) in a 0.5 M H2SO4 solution, respectively. The electroactive surface area (Aes) and roughness factor (frs) of each Ti disc were estimated from capacitance measurements of the electrochemical double layer. The morphology and voltammetric behavior of Ti varied markedly depending on the surface treatment applied. In addition, the XRD results showed that Ti surfaces subjected to different treatments exhibited different crystallographic planes. The trend in surface roughness with respect to the chemical reagent used was as follows: Group A: oxalic acid > HF/H3PO4 > global treatment > acetone > HCl; Group B: oxalic acid > HF/H3PO4 > NaOH > HCl > global treatment. The most severe chemical attack on the substrate was induced by oxalic acid, which led to the largest electroactive area and roughness factor among the treated Ti samples investigated in this study.

Numerical simulation study of combined shot peening and laser shock peening on surface integrity of Ti-6Al-4V titanium alloy

Combined shot peening and laser shock peening (CSP) can introduce high surface compressive residual stress (CRS) and deep CRS layer, and reduce the high surface roughness caused by shot peening. The relationship between CSP sequences and surface integrity, including CRS and surface roughness, is far from satisfying the actual demand. In this paper, we construct a finite element model considering initial surface profile features. The experimental results agree with the simulated results. Based on the simulation results, axial and longitudinal stress wave transfer effects on surface CRS and depth CRS are investigated. Compared with shot peening (SP) and laser shock peening (LSP) alone, CSP treatment can increase CRS depth and CRS magnitude by 1060 μm and 50 ∼ 80Mpa, respectively. In addition, the roughness following CSP treatment is lower than that observed after SP treatment alone, and the roughness varies depending on the sequence of CSP treatment. Specifically, the roughness values for SP, SP + LSP, and LSP + SP are 0.938 ± 0.031 μm, 0.982 ± 0.11 μm, and 1.168 ± 0.093 μm, respectively. The surface morphology, hardness, and simulation results are combined to reveal the reasons for the reduction of surface roughness after CSP treatment. The changes of peaks and valleys after CSP treatment compared with single SP treatment were studied, and the variation trend of surface roughness was further explained.

Assessment of Surface Quality during EDM of AISI 4147 with Copper Tool

This experimental assessment is performed to estimate the impact of EDM parameters on surface quality while machining AISI 4147 with a copper tool. The need of the present-day is to achieve good surface quality. Here, an investigation was performed to depict surface quality characteristics with respect to machine variables. The machined specimens were examined under white light interferometry (WLI) for the crests and troughs developed post-machining. The range of average surface finish was found to be between 5.32 to 7.67 µm. The test of model highlighted that the relation linking the EDM variables and surface roughness could be modelled using quadratic equations. As per the SMSS and lack of fit tests, a quadratic model is suggested for the roughness trend obtained. The analysis apprised that duration (p-value = 0.0006) major influence on the surface quality produced while the depth of machining (p-value = 0.9251). At all levels of on time, the surface roughness initially increases and then tends to decrease on increasing peak current. At all current levels, the surface roughness is almost constant with the machining depth; as suggested by ANOVA, it is the least influencing factor. At all levels of duration, the surface roughness is almost constant with depth of machining, and as suggested by ANOVA, it is the least influential factor. Model surface plots are curved representing the presence of quadratic terms in the model. Model validation for surface finish showed that the residual error was lower than 1.48%, proving the adequacy of the model.

Dynamic process of wet etching using BOE solutions to control the etch rate, roughness, and surface morphology of a Z-cut α-quartz wafer

Quartz is a widely used material in the field of microelectromechanical systems (MEMS) for fabricating devices such as substrates, probes, and lenses; it is also indispensable as a resonator or oscillator for frequency control in communication and network technologies. However, its development is limited because it is difficult to fabricate an ideal profile for implementation in complex structures. In practice, wet etching is the most effective and extensive method for achieving the expected structure, although dry etching and other special machining techniques have also been investigated. In this study, the dynamic wet etching process was recorded using different ratios of buffered oxide etcher (BOE) solutions as the etchant to reveal the etching mechanism. The experiments were first designed considering the fabrication of samples, experimental conditions, and measurement indicators. Subsequently, the corresponding etch rate, roughness, and surface morphology were investigated to control the process parameters during wet etching. Different etchants exhibit varying etching rates and roughness properties. A smaller proportion of hydrofluoric acid in the BOE solution results in lower etch rate, and vice versa. The roughness (Ra) in the stable stage was not completely consistent with the tendency of the etch rate, whereas the surface morphology and dimensions of the pyramids rationally complied with the roughness trend. Additionally, the results suggested that the three following stages exist during the wet etching process of the z-cut α-quartz wafer; smooth, incremental, and stable. The analysis of the dynamic wet etching process in this study is beneficial for the structural design, manufacturing, and performance of quartz MEMS devices.

MSSPN: Automatic first-arrival picking using a multistage segmentation picking network

Picking the first arrival of prestack gathers is an indispensable step in seismic data processing. To enhance the efficiency of seismic data processing, some deep-learning-based methods for first-arrival picking have been developed. However, when applying currently trained models to data that significantly differ from the training set, the results are often suboptimal. We refer to this predictive scenario as cross-survey picking. Therefore, further improving model generalization for accurate cross-survey picking has become an urgent problem. To overcome the problem, we develop a multistage picking method called multistage segmentation picking network (MSSPN), which breaks down the complex picking task into four stages. In the first stage, we develop a coarse segmentation network to recognize a rough trend of first arrivals. Second, a robust trend estimation method is developed in the second stage to further obtain a tighter range of first arrivals. Third, a refined segmentation network is conducted in the third stage to pick high-precision first arrivals. Finally, we develop a velocity constraint-based postprocessing strategy to remove the outliers of network pickings. Extensive experiments indicate that MSSPN outperforms current state-of-the-art methods under the cross-survey test situation in terms of the metrics of accuracy and stability. Particularly, MSSPN achieves 94.64% and 89.74% accuracy under the cross-survey field cases of the median and low signal-to-noise ratio data, respectively.

The effect of surface energy on the wettability of graphene-coated copper: A comparison of different single and multilayer graphene

The present research investigated the effect of different types of graphene layers including a slow cooling rate single-layer graphene (SSLG), a high cooling rate single-layer graphene (HSLG), and a multilayer graphene (MLG) on the wettability and surface energy of the copper substrate, which was synthesized using a chemical vapor deposition (CVD) process. Results revealed an increasing trend in surface roughness of the substrate by applying the graphene layer which is mostly due to the formation of step bunches (SBs) during the synthesis process, and the highest surface roughness is obtained for the MLG. Moreover, despite the expectations the results of surface energy indicated that applying the graphene layer in all cases has increased the surface energy. However, the lowest surface energy is related to SSLG among the coated samples. On the contrary, the wettability of the coated-samples was diminished and the lowest wettability was obtained for the SSLG.

Assessment of surface irregularities created by controlled liquid droplet on the surface of stainless steel AISI 304L

Surfaces created by the erosive action of water droplets have not been sufficiently explored because of their stochastic structure, which depends on hydraulic parameters. This article details the complex analysis of surfaces created by the controlled distribution of water droplets on the surface of AISI 304L using an ultrasonically stimulated water jet. The traverse speed of the jet controlled the distribution of the water droplets. The surface topology was modified in an interleaved mode when the trajectories were parallel for all samples. Additionally, the second layer treated the other half of the preprepared samples with a perpendicular trajectory with respect to the parallel trajectory. The 3D surface reconstruction was performed using a noncontact MicroProf FRT measuring instrument. Several profile roughness parameters (Ra, Rz, Rv, Rp, Rsk, and Rku), areal surface roughness parameters (Sa, Sz, Sp, Sv, Ssk, Sku, Sdr, Sk, Spk, and Svk) and surface isotropy values were measured for the surfaces generated using variations in the traverse speed of the jet. The measurement results show a decreasing trend of surface roughness upon an increase in the traverse speed, and a better surface finish was also measured for the cross-hatch trajectory compared to the linear trajectory. The results also show that the generated surfaces have deeper valleys with truncated peaks, which are suitable for use in a wide range of technical and medical applications. This study shows the potential utilization of controlled liquid droplet impingement for surface preparation in various application domains.

Influence of Diamond Wire Saw Processing Parameters on the Sawn Surface Characteristics of Silicon Nitride Ceramics.

For the slicing of superhard silicon nitride ceramics, diamond wire sawing technology has great potential for application, and its slicing surface characteristics are an important indicator of cutting quality. In this paper, the sawing experiments of silicon nitride ceramics were carried out within the range of industrial processing parameters of diamond wire sawing (saw wire speed: 800-1600 m/min, workpiece feed speed 0.1-0.4 mm/min). The effects of cutting parameters on the surface morphology, surface roughness and waviness of the as-sawn slices were analyzed. The results show that within the range of sawing parameters for industrial applications, the material on the diamond wire as-sawn surface of silicon nitride ceramics is removed mainly in a brittle mode, with the slice morphology showing brittle pits and regularly distributed wire marks in the 20-55 μm scale range. The surface roughness of the slices along the workpiece feed direction ranges from 0.27 to 0.38 μm and decreases with increasing saw wire speed and decreasing feed rate. The surface waviness ranges from 0.09 to 0.21 μm, which is in good agreement with the changing trend of the sliced-surface roughness. The results of the study provide an experimental reference for promoting the engineering application of diamond wire sawing technology to the processing of silicon nitride ceramic slices.

Studied validation of finite element modeling for titanium alloy (Ti–6Al–4V) at face milling

BackgroundDue to its qualities, There is a lot of use of the titanium alloy (Ti–6Al–4V) in gas turbines and other aero engines. It is difficult to determine machining parameters such cutting force, temperature, and surface roughness, and it is difficult to calculate these values using analytical methods. The finite element method (FEM) is a particularly useful platform for studies since it predicts the machining parameters. MethodsThe advantage of this method is taken for the purpose of linking the mechanical and thermal equations based on a step of the dynamic, temperature-displacement, explicit of the Lagrangian formulation in a new model that is fully thermomechanically connected. Three mesh areas were created for optimizing the cutting zone during the cutting simulation process. The machining process by using a face milling tests was carried out. There are two variable factors of cut such as feed rate, cutting speed are created randomly when depth is a constant parameter. High-speed camera used to capture the machining process which determines the important details of spark generated. Findings and interpretationThere is a very excellent agreement between the experimental data and the simulation results from the finite element modeling (FEM). By raising the feed rate in the cutting zone, the cutting temperature can be raised and a spark can be generated. This led to the conclusion that surface roughness trends can be predicted using feed cutting force measurements. Surface roughness rose in direct proportion to the magnitude of the feed cutting force, and vice versa.

Orbital and physical parameters of eclipsing binaries from the Optical Gravitational Lensing Experiment catalogue: testing the tidal circularization

ABSTRACT Tidal forces are an important process in the pre-main-sequence phase (as reported by Zahn and Bouchet in their now well-known paper) and throughout the main-sequence phase of stellar evolution. Nevertheless, uncertainty over tidal forces affects estimates obtained from models of the circularization and synchronization of the orbit by tidal interactions. Here, we search for evidence of tidal circularization in close binaries using a large sample of well-characterized eclipsing systems. We searched Optical Gravitational Lensing Experiment (OGLE) photometric catalogue for the Southern hemisphere from the Southern hemisphere for eclipsing binaries in eccentric orbits. We present precise values of the eccentricity and orbital and stellar parameters of eight detached, eclipsing stars from the OGLE catalogue that were determined by jointly modelling light curves and spectral analysis. The temperatures and relative radii of their components, as well as their mass ratios, were also calculated with high accuracy. We find a clear dependence of the components' relative radii and orbital period on the eccentricity. The determination of eccentricities as a function of period potentially allows us to infer the role of tidal circularization. The (P, r1,2) distribution of the known eccentric binaries exhibits a rough trend of increasing eccentricity with period. This suggests that the secondary components in binaries with longer orbital periods may be tidally circularized significantly more efficiently than is usually assumed. Observing this effect is challenging because it requires large and well-characterized samples that include many types of systems. Here we seek evidence of the predicted dependence of circularization on the relative radii using a sample of eclipsing binaries observed by OGLE.

Fire Detection with Image Processing using Live Camera

People's safety and property can only be saved if the fire alarm signal is precisely detected and identified as early as possible in the fire, which is a terrible catastrophe for the security of people's lives and properties. Fire detection accuracy and validity are degraded as a result of growing ambiguity in the fire signal. – An algorithm for the detection of one dimensional fire space is provided to demonstrate the suggested method's fine fault tolerance, robustness, and accuracy in a novel technique for detecting uncertainty fire signals based on fire scenarios. First, an analysis of fire scenario performance yields a fractal character for the fire space, and then an intelligent method based on rough set theory and trend integration is used to process the multi-source signal obtained from a group of fire detectors. When a relationship between the two characters is recognised as being logically coincident, an actual alarm for a fire is triggered.

Analysis of Tool Wear and Roughness of Graphite Surfaces Machined Using MCD and NCD-Coated Ball Endmills.

The high-purity G5 graphite material is widely used for glass moulding and provides high hardness and brittleness because it is sintered to fine particles unlike other graphite materials. Hence, tool cutting of a G5 workpiece is performed by local fracture instead of plastic deformation of the machined surface. Although a diamond-coated tool with outstanding hardness is used to machine very hard graphite, the tool shows variability regarding the service life and machining performance depending on the grain size, even in the same machining environment. We investigated the wear and change trend of machined surface roughness considering microcrystalline diamond (MCD) and nanocrystalline diamond (NCD)-coated tools, which are generally used to machine graphite materials, and analysed their relation with coating. For rough machining, the MCD-coated tool, for which the delamination of coating occurred later, showed less wear and improved machined surface roughness. For precision machining, the NCD tool showed less tool wear rate relative to the cutting length, leading to a small difference in the machined surface roughness between the two tools. We conclude that if rough and precision machining processes are performed using the same cutting tool, the MCD-coated tool is advantageous in terms of service life, while the difference in roughness of the final machined surface between the tools is negligible.

Sample entropy based prescribed performance control for tailless aircraft

This paper proposes a sample entropy (SampEn) based prescribed performance controller (SPPC) for the longitudinal control of a supersonic tailless aircraft subject to model uncertainty and nonlinearity. Considering that SampEn can evaluate the system’s stability, a SampEn-based feedback adjust system (SFAS) is developed in this paper. With the help of SFAS, the SPPC could identify the dangerous chattering in the status signal that may lead the aircraft to lose control and make appropriate adjustments to feedback. Besides, the SPPC does not require any accurate model information and only needs to know the rough trend of dynamic functions. Although no adaptive or robust control mechanisms are introduced, the SPPC shows robustness against model uncertainty utilizing the nonlinear error feedback. Compared with traditional prescribed performance control (TPPC), the SPPC achieves better performance and safer flight. The whole control structure is developed through the backstepping technique, and the closed-loop stability is proved. At last, the advance of SPPC is verified via simulation using a high-fidelity tailless aircraft model, and the inner mechanisms of SPPC are further discussed.

Online Surface Roughness Prediction for Assembly Interfaces of Vertical Tail Integrating Tool Wear under Variable Cutting Parameters.

Monitoring surface quality during machining has considerable practical significance for the performance of high-value products, particularly for their assembly interfaces. Surface roughness is the most important metric of surface quality. Currently, the research on online surface roughness prediction has several limitations. The effect of tool wear variation on surface roughness is seldom considered in machining. In addition, the deterioration trend of surface roughness and tool wear differs under variable cutting parameters. The prediction models trained under one set of cutting parameters fail when cutting parameters change. Accordingly, to timely monitor the surface quality of assembly interfaces of high-value products, this paper proposes a surface roughness prediction method that considers the tool wear variation under variable cutting parameters. In this method, a stacked autoencoder and long short-term memory network (SAE–LSTM) is designed as the fundamental surface roughness prediction model using tool wear conditions and sensor signals as inputs. The transfer learning strategy is applied to the SAE–LSTM such that the surface roughness online prediction under variable cutting parameters can be realized. Machining experiments for the assembly interface (using Ti6Al4V as material) of an aircraft’s vertical tail are conducted, and monitoring data are used to validate the proposed method. Ablation studies are implemented to evaluate the key modules of the proposed model. The experimental results show that the proposed method outperforms other models and is capable of tracking the true surface roughness with time. Specifically, the minimum values of the root mean square error and mean absolute percentage error of the prediction results after transfer learning are 0.027 μm and 1.56%, respectively.

Effect of defocusing distance on the forming quality of inner structure parts manufactured via selective laser melting

A systematical work was studied to illustrate the influence of defocusing distance on the forming quality of inner structure fabricated by selective laser melting for Ti-6Al-4V alloy. The relationship between defocusing distance and dimensional accuracy, surface roughness as well as flatness was investigated, finite element analysis (FEA) was used to show the temperature distribution. The results show that defocusing distance not only had an impact on laser energy density, but also showed a significant influence on the surface pressure of the metal powder. Smaller defocusing distance (0.0 mm) accompanied with higher molten pool maximum temperature (3262.96°C), powder melting and splashing at the same time. On the contrary, larger defocusing distance leading to unmelted powder and powder bonding, which influences the forming quality of samples. Dimensional accuracy was less affected in 0.0, 1.0, 2.0 mm defocusing distance (5%), but changed dramatically when it is 3.0 mm (22%). In the same condition, similar variation trend of surface roughness (Ra) and flatness was observed, and varying from 5.1 to 27.3 μm and 0.05 to 0.26 mm, respectively. Simultaneously, the bottom surface is less affected, while the other three sides have the opposite situation. Pores and unmelted powder can be seen on the surface, it is the comprehensive effect of laser energy density and surface pressure. It proves that it is feasible to manufacture inner structure by controlling this process parameter during SLM process, the influence mechanism of defocusing distance on forming quality was also illustrated in this work.

Calcium-doped titanium thin films prepared with the assistance of an oxygen ion beam: The effect of Ca content on microstructure, mechanical properties and adhesion

The effect of adding calcium on the microstructural evolution and properties of the Ti-Ca-O system has been investigated. Calcium-doped titanium (Ti-Ca) thin films were prepared by dual electron beam deposition with the assistance of an oxygen ion beam. The films were characterized by glow discharge optical emission spectroscopy (GD-OES), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), to determine the elemental composition, chemical bonds and crystallinity. Oxygen ion assistance produces non-completely oxidized Ti-Ca films. The addition of calcium led to increased formation and stabilization of titanium oxides in the titanium matrix under conditions of oxygen deficiency. Replacement of Ti by Ca in TiO and TiO2 was observed, rather than the formation of a CaO and TiCaO mixture. Compound formation, crystallite growth and lattice expansion with rising Ca concentration induced an increase in mechanical properties (hardness and reduced elastic modulus) and surface roughness. High Ca concentration (5 at%) led to a significant reduction in mechanical properties, and above 1 at% led to a significant reduction in adhesion strength. The Ti-Ca films showed hydrophobic behaviour. The water contact angle followed the increasing trend of Ca concentration and surface roughness. There is a discussion of the changes in the studied properties.