Values Of Surface Roughness Parameters Research Articles

Enhanced technique for photochemical nano-polishing of a rough quartz surface: the numerical calculation of profile evolution.

The enhanced technique of quartz surface nano-local etching is considered. The enhancement of an evanescent field above surface protrusions and, as a result, an increase in the rate of quartz nano-local etching, are proposed. The possibility to reduce the amount of etch products filled in rough surface troughs and control the optimal rate of the surface nano-polishing process is achieved. The dependences of the quartz surface profile evolution on the initial values of surface roughness parameters, on the refractive index of the medium containing molecular chlorine and contacting the quartz surface, and on the wavelength of radiation illuminating this surface are shown.

Evaluation of surface roughness parameters of anatomical structures models of the mandible made with additive techniques from selected polymeric materials

Making a template or implant for surgery is not a simple task. This is especially true of the craniofacial area, which consists of bone tissues with a very complex geometry. Titanium alloys are still used in medicine as implantable materials. However, due to the continuous improvement of mechanical and functional properties, the scope of polymeric materials application in medicine is expanding. Each model used directly or indirectly during a surgical procedure must meet many conditions. One of them is to obtain the appropriate condition of the surface layer, which has a significant impact on the reactions between the applied surgical template or implant and the living organism. Knowledge of the printed models made of polymeric materials surface roughness parameters may allow the targeted modification planning of the surface layer, allowing better application during the procedure. In this study, the research on the comparative analysis of the obtained values of surface roughness parameters of the anatomical structures of the mandible made of selected polymer materials with the use of additive techniques was presented. In the research process, the following materials were used: polylactic acid (PLA), polycarbonate (PC), three photo polyacrylic resins (marked in the manuscript as AR1, AR2 and AR3) and polyamide (PA11). On the basis of them, physical models of the mandible lateral sections were made using 3D printing techniques. Measurements of the model surfaces geometric structure were carried out using a 3D contact profilometer. In the process of determining the surface roughness, the measurement data was filtered in accordance with the ISO 4288 standard. As a final result, selected amplitude parameters and three-dimensional visualization of the surface roughness of the tested models were presented.

Influence of post-processing techniques on the microstructure, properties and surface integrity of Al Si Mg alloy processed by laser powder bed fusion technique

The present work investigates the influence of post-processing techniques such as heat treatments (T5 and T6 conditions) and the shot peening (SP) under peening pressures such as 3 bar (SP-3) and 6 bar (SP-6) on the LPBF processed AlSi10Mg alloy. The microstructures of as-printed and heat-treated samples revealed a density of greater than 99.9%. The micro-hardness, yield and tensile strength properties were similar in both as-printed and heat-treated (T5) conditions. However, the samples of the heat-treated (T6) showed lower micro-hardness, yield and tensile strength properties than as-printed and heat-treated (T5) samples. There was a significant decrease in surface roughness and a notable improvement in surface hardness for shot-peened samples compared to the as-printed samples. SP process decreased the surface roughness parameter values by more than about ~50% compared to the as-printed samples. The SP-3 condition induced a smoother surface (~12%) than the SP-6 condition on the LPBF processed AlSi10Mg samples. Overall, the employed post-processing techniques such as heat treatment and shot peening on the LPBF processed AlSi10Mg alloy exhibit improved isotropic mechanical properties and surface integrity. • Post-processing techniques such as heat treatments and the shot peening on the LPBF processed AlSi10Mg alloy is studied. • The micro-hardness and tensile properties of T5 were higher than T6 conditions. • SP process decreased the surface roughness by more than about ~50% compared to the as-printed samples. • The SP-3 condition induced a smoother surface (~12%) than the SP-6 condition.

Soil moisture retrieval over agricultural fields through integration of synthetic aperture radar and optical images

ABSTRACT The soil roughness and two-way vegetation transmissivity parameters affect the radar backscattered signal; therefore, the results of the soil moisture retrieval from Synthetic Aperture Radar (SAR) images. In this paper, the Improved Water Cloud Model was extended to specify the effects of the above parameters. The surface roughness parameter values were calculated for each ground measurement site using an artificial neural network. This parameter was then used in the proposed models to rectify the effects of surface roughness on soil moisture estimation. Also, the Normalized Difference Water Index, derived from Landsat 5 imagery, was used to account for the impact of the vegetation canopy on the SAR backscatter. The accuracy of the proposed model was assessed using AIRSAR C-, L-, and P-band data, ALOS PALSAR L-band and two reference data were collected during NASA’s SMEX03 and SMAPVEX08 campaigns. The experimental results indicated that the proposed models had improved the RMSE and R values with respect to those in the IWCM in all bands and polarizations, with the highest values concerning the L band and VV polarization. In this band, the value of RMSE decreased by 0.002 (6.25%), and R increased by 0.054 (9.45%).

The Influence of Battery Acid on the Destruction of Acrylic Coatings of Car Bodies

Renovation coatings of car bodies undergo destruction under the influence of operational factors. Like ultraviolet radiation, erosion, and aggressive media (among others, battery acid). This article concerns the evaluation of the influence of battery acid on the destruction of acrylic coatings previously non-aged, as well as aged climatically for 2 years. Ageing of the coatings with battery acid contributed to a degradation increase of their chemical structure. It was supported by a considerable increase in the polar component of surface free energy (SFE) of the coatings. In the case of prior climate ageing, the increase in the polar component was even higher. Moreover, the coating’s ability to absorb battery acid increased, which induced blistering. The DSC method revealed that the action of battery acid caused more intense oxidation of coating material, and as a result, the brittleness increased, leading to chipping of the coating surface layers. This led to the increase in surface roughness, measured using an interferometric method. The coatings previously climatically aged for 2 years presented higher values of surface roughness parameters than the non-aged ones. The increase in the surface roughness contributed to a substantial decrease in the gloss of coatings. A sharp difference in colour escalating with the lengthening of the ageing period was also observed using the spectrophotometric method.

Research on the Effects of Roughness on the Tactile Properties of Rice Straw Particleboard Surface

To explore the effects of roughness on the tactile properties of rice straw particleboard (RSP), the surface roughness and psychological tactile and visual experiments were conducted for RSP substrates with 0.76 g/cm3 and 0.55 g/cm3 densities after sanding with sandpaper (mesh 180#, 360#, and 600#). The effects of different sandpaper types, sanding time, and density of RSP on the surface roughness were analyzed. The experimental results are as follows. The sanding treatment had significant influence on the surface roughness characterization parameters Ra and Rpv of the RSP specimens. Surface roughness differences between the 180# and 360# mesh-prepared samples were obvious. The tactile and visual psychological values of the 360# and 600# mesh-sanded specimens were higher, and the psychological quantities of untreated and 180# mesh-sanded specimens were lower. After comparing the samples with sanding treatment of sandpaper 0∼180#, the change in surface roughness of RSP with a density of 0.76 g/cm3 was smaller than that of the specimen with a density of 0.55 g/cm3. The psychological quantity difference of RSP specimens with a density of 0.55 g/cm3 was evident. When the sanding time was 1 min., the values of the roughness characterization parameters Ra and Rpv increased slightly. After 3 min. sanding, the Ra and Rpv values stabilized. When the sanding time was 5 min, the roughness was essentially unchanged. With the change in sanding time, the measured values of the tactile psychological quantity varied greatly and the measured values of the visual psychology were very close. For the RSP substrates with higher density, the surface roughness was less after sanding with a smoother surface and better tactile properties. There were significant differences between the surface roughness of the RSPs before and after sanding. After manual sanding over the same time span, the surface roughness evaluation parameter values decreased with an increase of mesh size of the sandpaper, and the tactile properties were improved. The longer the sanding time, the smaller the difference in the surface roughness parameter values, and the smaller the difference between the tactile psychological quantity and the visual psychological quantity. To expand the research scope of RSP products, this study investigates not only the physical and chemical properties but also the subjective feelings when using the RSP products. This will provide analytical methods and design guidelines for the consideration of environmental factors in furniture and interior design.

Towards an Intelligent Approach for the Restitution of Physical Soil Parameters

The analysis of the radar response on natural surfaces has been subject of intense research during the last decades in the field of remote sensing. Unless the availability of accurate values of surface roughness parameter, the restitution of soil moisture from radar backscattering signal can constantly provide inaccurate estimates. Characterization of soil roughness is not fully understood, so a wide range of roughness values can be obtained for the same studied surface when using different measurement methodologies. Various studies have shown a weak agreement between experimental measurements of soil physical parameters and theoretical values under natural conditions. Due to this nonlinearity and its ill-posedness, the inversion of backscattering radar signal on soils for restitution of physical soil parameters is particularly complex. The aim of the present work is the restitution of soil physical parameters from backscattered radar signal using an adapted backscattering model to the soil proposed description. As our study focuses on little rough soils, we have adopted in this work a multi-layered modified multiscale bi-dimensional Small Perturbation Model (2D MLS SPM). Subsequently, we propose a new way of describing the dielectric constant, with the aim of including air fractions in the multiscale multilayer description of the soil. Calculating the dielectric constant is based on the consideration of a soil comprising two phases, a fraction of soil, and an air fraction. For the inversion method, a methodology of coupling between neural networks (NN) and genetic algorithms (GA) was carried on in order to restitute the physical properties of the soil. Samples were generated by the original MLS 2D SPM followed by a neural network to obtain the statistic soil moisture and MLS roughness parameters algorithm. thereafter, these restored values were modelled by the genetic algorithms to resolve, in part or in whole, the disagreement between the retrieval and original values.

Istraživanje i optimizacija uticaja parametara obrade na hrapavost površine kod obrade AISI 4340 čelika

This paper focuses on the experimental investigation of machining parameters such as cutting speed, feed rate and depth of cut influence over surface roughness parameters (Ra, Ry and Rt) during turning AISI 4340 steel. Further, in order to achieve smaller surface roughness parameter values, the machining parameters are optimized using Taguchi's technique Signal-to-Noise ratio (S/N ratio). Analysis of Variance (ANOVA) is performed to determine the most contributing factor that influences the surface roughness parameters. It is observed that the feed rate is the most significant factor contributing by 70.50%, depth of cut by 18.54% and cutting speed by 9.15%. From the optimum condition obtained, a confirmation experiment is performed and the results obtained shows that the surface roughness parameter values are reduced by 31.63% than the designed experimental values.

The Influence of Cutting Parameters on Surface Topography During Turning Marine Pump Shafts

Abstract One of the greatest problems of modern production techniques is the achievement of an appropriate quality at minimal costs and accompanied by the production efficiency increase. Therefore, while designing the production process. The technology used should have a considerable influence on the durability and reliability of machine parts to be produced. During finish treatment, the final dimensions as well as functional properties are imparted to a given element by application of proper treatment type. The engineer has a range of production techniques to choose for the proper surface layer formation. Conventional turning machines belong to the basic equipment of ships, because in sea conditions, they enable the execution of a spare part or carrying out the necessary operations in the process of their regeneration. The use of modern cutting tools makes it possible to obtain a surface with low values of surface roughness parameters. The use of new generation cutting inserts on conventional lathes can cause problems for operators. The lack of the ability to ensure proper of treatment condition and setting errors of cutting tools contribute to the damage of the cutting insert or the surface of the workpiece. The article presents the results of influence of different cutting parameters on surface topography during turning process of stainless steel. A shaft made of 304L stainless steel was used for the research. The cutting process was carried out on a universal TUM 25B x 500 centre lathes. During the turning the following machining parameters were used: cutting speed Vc [m/min], feed f [mm/rev] and depth of cut ap [mm].The turning process was conducted by a cutting tool with CCGT 09T302 UM, CCGT 09T304 UM and CCGT 09T308 UM inserts. Measurement of surface topography was carried out by T8000 profilometer.

Surface quality simulation with neural networks in AZ91D Mg alloy milling

The mathematical model presented in this paper describes the process of milling AZ91D Mg alloy with the TiAlN-coated tool. The experimental data from the neural network training served to determine the effect of various milling parameters on the surface roughness of the workpiece. The 2D roughness measurements were taken on the end-faces of specimens and focused on the set of three parameters – Ra, Rz and RSm. The tests were performed at constant parameters (tool geometry, workpiece strength properties and technological machine properties), variable parameters (cutting speed, feed per tooth, depth of cut) and output variables (Ra, Rz, Rsm). The simulations were executed by means of the artificial neural networks, modelled with Statistica Neural Network software. Two types of neural networks were employed: MLP (Multilayered Perceptron) and RBF (Radial Basis Function). The comparative analysis showed that the discrepancy between the results of simulation and the results obtained from experimental tests is on an acceptable level, not exceeding 15%. The above result confirms that ANNs can be successfully used as a tool for a selection of technological parameters, enabling obtaining the desired values of surface roughness parameters without the need for time-consuming machining tests.

“Mechanically prepared copper surface in oxidizing and non-oxidizing conditions”

In the present work surface roughness of copper samples after mechanical surface preparation processes (polishing, grinding, sand-blasting) and after exposure in non-oxidizing (high purity argon) and oxidizing (air) conditions at 700 and 750 °C have been evaluated by contact profilometer and by fractal analysis. Quantitative description of surfaces that are hidden from the sight of conventional methods is possible by fractal analysis, e.g. in the present work, the roughness of Cu2O/Cu boundary has been evaluated under oxide layer. It has been pointed out, that in both oxidizing and non-oxidizing conditions initial surface roughness of copper is affected by annealing at high temperature: at 700 °C surface roughness of polished and ground samples increased but at 750 °C decreased in comparison to surface roughness prior to heat treatment. For sand-blasted samples in both oxidizing and non-oxidizing conditions the lowest values of surface roughness parameters were obtained at 750 °C. It is then concluded that two phenomena are responsible for such effect: chemical reaction between copper and oxygen and surface diffusion of copper due to high temperature of annealing.

Effect of Recasted Material Addition on the Quality of Metal-Ceramic Bond: A Macro-, Micro-, and Nanostudy

Using the recasted alloys in dental prosthetics could affect the quality of the metal-ceramic bond. However, scientists, alloys producers, and prosthetists are still of different opinions. The purpose of this study was to estimate the influence of recasting of the NiCrMo alloy on the metal-ceramic bond quality. The research was carried out on macro-, micro- and nanoscales using the three-point bending test procedure and hardness tests as well as atomic force microscopy and SEM analyses. The SEM analyses showed good integrity of the metal-ceramic bond. The τb index of all test samples was greater than 45 MPa. The highest values were recorded for the samples made of 50% and 100% of a brand new material. SEM analysis made after the bending test confirmed good metal-ceramic bond and exhibited adhesive-cohesive fracture. The largest hardness of metal plates was found for the samples containing 50% of the recycled material. Atomic force microscopy studies showed that the alloy containing 50% of the recycled material was characterized by the highest values of surface roughness parameters.

Polished surface roughness of optoelectronic components made of monocrystalline materials

A study of the mechanism of formation of monocrystal planes of different crystallographic orientations has revealed that in polishing of sapphire the surface roughness parameters Ra, Rq, Rmax decrease in the series c > r > m > a with decreasing dielectric permittivity and thermal conductivity coefficient of the workpiece material, debris particle height, and Lifshitz constant that represents the energy of interaction between the polishing powder grains and the workpiece surface. The minimum allowable values of surface roughness parameters for atomically smooth surfaces have been defined, which linearly depend on interplanar spacings and decrease in the series r > a > c > m.

Experimental studies of the cutting force and surface morphology of explosively clad Ti–steel plates

The present work pertains to the study of clad material such as titanium plated steel in drilling process. The study was conducted for two types of indexable insert drills with different configuration of the tool coatings (TiAlN/AlTiN+TiN and TiAlN/TiN), the same geometry of insert and fixed machining conditions. Drilling process was assessed by the analysis of thrust force, torque and signal fluctuations of PSD function. In this context, surface morphology of the drilled holes and contact area was analysed. It has been observed that the use of the PSD function allows assessment of the drilling process in different layers of clad materials. Also was found that the parameters of the surface morphology are dependent upon the type of layers of the clad and the type of drill. Furthermore the reduction in torque results in obtaining smaller values of surface roughness parameter especially in the area of volume parameters of the bearing area curve.

The electrochemical behavior of Co(TPTZ)2 complex on different carbon based electrodes modified with TiO2 nanoparticles

Electrochemical behavior of cobalt (II) complex with the N-donor ligand 2,2′-bipyridyl-1,3,5-tripyridyl-s-triazine (TPTZ) was investigated to elucidate the electron-proton transfer mechanisms. The electrochemical response of the complex was studied using square-wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS) techniques. A conventional three-electrode system, consisting of glassy carbon (GCE), TiO2 modified glassy carbon (T/GCE), carbon paste (CPE) and TiO2 modified carbon paste (T/CPE) working electrodes were employed. The ligand/metal ratio and stability constant of the complex as well as the mechanisms of the electrode processes were elucidated by examining the effects of pH, ligand concentration and frequency on the voltammograms. The EIS results indicated that the samples modified with TiO2 had the higher charge transfer resistance than that of the bare electrodes and also suggested that the electroactivity of the electrode surfaces increased in the following order, T/CPE > CPE > T/GCE > GCE. The surface morphology of the working electrodes was also characterized by atomic force microscopy (AFM). The values of surface roughness parameters were found to be consistent with the results obtained by EIS experiments.

Evaluation of wood surface roughness depending on species characteristics

This study is focused on the impacts of species characteristics on the surface roughness of five species with different wood density namely white fir, Aleppo pine, European beech, walnut and white oak. The sample specimens tested were 300x300x30 mm in size and their surface quality was evaluated by the “the direct contact method” based on a mechanical system of measurement, giving the possibility of reproducing the surface measured and analyzing its profile. The surface roughness measurements were performed with a contact stylus profilometer, holding the moisture content of the specimens constant at 10%. The evaluation of the surface characteristics of the wood samples considered the roughness parameters: arithmetic mean deviation of the profile, maximum two point height of the profile, mean roughness depth and root-mean-square deviation of the profile. From the study result showed different average values of surface roughness parameters for broadleaved and conifers species. The differences can be explain by the influence on the roughness of the wood surface of the wood texture and the texture uniformity.

Evaluation of 3D Surface Roughness Parameters of EDM Components Using Vision System

Surface roughness evaluation is very important for many fundamental problems such as friction, contact deformation, tightness of contact joints positional accuracy etc. Many techniques have been developed for measuring surface finish ranging from the simple touch comparator to sophisticated optical techniques. In recent years, the advent of high-speed general-purpose digital computers and vision systems has made image analysis easier and more flexible. Unlike the stylus instruments, computer vision systems have the advantages of being non-contact and are capable of measuring an area from the surface rather than a single line. A vision system is considered relatively cheap, fast and suitable for automation.Work pieces are prepared with varied roughness using manufacturing process of EDM and subjected to different machining parameters such as variable current and voltage. The proposed method used vision system. Vision system consists of a CCD camera, frame grabber, advanced image processing card and a high end computer. The surface images are grabbed using CCD camera and then transferred to the computer memory through frame grabber. An image processing algorithm is prepared using MATLAB. The surface roughness parameter values (3D) obtained by Vision system are then compared with those obtained by Optical method. Strong correlation is obtained between the vision roughness and optical roughness parameters. Hence the proposed method can be used in the assessment of 3D surface finish. The complete analysis of results is presented in this work.

Comparison of Theoretical and Real Surface Roughness in Face Milling with Octagonal and Circular Inserts

Various modeling techniques have applied by researchers to predict values of surface roughness parameters in different metal cutting processes. Some examples of these methods are briefly introduced. After this an analytical model and investigation method are presented which were used to make predictions of the expected values of surface roughness parameters. Cutting experiments were performed to obtain real roughness data and to validate the proposed and realised model by face milling of 42CrMo4 specimens with two different insert shapes. Conditions and results of these experimental investigations are presented in the subsequent part of the paper, and finally the determined approximation relations are introduced that can be used to calculate the expected roughness values from theoretical data.

Surface Roughness Minimization in Turning PEEK-CF30 Composites with TiN Cutting Tools Using Particle Swarm Optimization

Poly ether ether ketone (PEEK) composite belongs to a group of high performance thermoplastic polymers and the addition of carbon fibers increases the resistance and rigidity of PEEK. Due to favorable mechanical and thermal properties and potential applications in various manufacturing industries, it is essential to analyze the machining performance of reinforced PEEK composites. The surface roughness is a widely used measure of product quality that could influence the performance of mechanical products and production costs. The present study establishes the relationships between the cutting conditions (cutting speed and feed rate) and three surface roughness parameters (centerline average surface roughness, maximum peak to valley height and root mean square roughness) by developing second order mathematical models based on response surface methodology (RSM). The reinforced PEEK with 30% of carbon fiber (PEEK-CF30) workpieces were machined using TiN-cutting tools. The experiments have been planned as per full factorial design of experiments (FFD). The developed surface roughness models were then employed with particle swarm optimization (PSO) to optimize the cutting conditions. PSO program gives the minimum values of surface roughness parameters and the corresponding optimal cutting conditions.

Characterization of surface roughness of unworn hydrogel contact lenses at a nanometric scale using methods of modern metrology

The aim of this study was to qualitatively and quantitatively characterize the optic surface topography of unworn hydrogel contact lenses (CLs) using atomic force microscopy (AFM) analysis and methods of modern metrology. The CLs used in this study were vifilcon A (Focus® Monthly Toric Visitint® model, CIBA Vision Corp.). AFM analysis was performed in Tapping Mode™ in an aqueous environment. The surface roughness analysis was based on six quantitative statistical parameters: arithmetic mean deviation of the surface (Sa), root mean square deviation of the surface (Sq), skewness of the topography height distribution (Ssk), kurtosis of the topography height distribution (Sku), 10-point average of the absolute heights (Sz), and vertical distance between highest peak and lowest surface point (St). These parameters were determined across different square areas (1, 4, 9, 16, and 25 μm2). The surface roughness parameter values were found to be dependent on the examined surface area. The values of Sa, Sq,|Ssk|, Sz, and St parameters increase with the increasing size of the scanning area, an opposite effect of that observed for the Sku parameter values. The proposed methodology might potentially have implications for the future testing of contact lens hydrophilic polymers. POLYM. ENG. SCI., 53:2141–2150, 2013. © 2013 Society of Plastics Engineers