Minimum Surface Roughness Value Research Articles

Effect of sodium tungstate concentration on surface morphology and hardness variation of 6063 aluminium alloy using by plasma electrolytic oxidation

Abstract The coatings were prepared on the surface of 6063 aluminium alloy using by plasma electrolytic oxidation in a sodium tungstate (Na2WO4) electrolyte solution with concentration varying from 0.017 to 0.068 mol/L. The power of plasma electrolytic oxidation is about 600 W, electrolysis time is 20 and 30 minutes, respectively. In this study using sodium tungstate as the main component of the electrolyte without any additives. The effects of Na2WO4 concentrations on the surface morphology and hardness variation of the 6063 aluminium alloys are investigated. These oxide films on aluminium were characterized by laser scanning confocal microscope, scanning electron microscopy (SEM) and Vickers microhardness indenter (Hv), respectively. The results reveal Na2WO4 electrolyte solution with concentration varying from 0.017, 0.034, 0.051 to 0.068 mol/L. When the electrolyte concentration is 0.034 mol/L, the maximum hardness value is 104 Hv after plasma electrolytic oxidation for 20 minutes. When the electrolyte concentration is 0.051 mol/L, the minimum surface roughness value obtained by plasma electrolytic oxidation for 30 minutes is Sa 0.324 μm.

Experimental Study on Dry Milling of Stir-Casted and Heat-Treated Mg-Gd-Y-Er Alloy Using TOPSIS

This study examines the dry milling process of a rare-earth-based magnesium alloy, emphasizing the optimization of the milling parameters and their impact on the surface quality, cutting forces, and the rate of material removal. The objective is to improve our comprehension of the milling behavior of the Mg-Gd-Y-Er alloy. The Taguchi technique is adopted to formulate the experimental design. This study methodically investigates the influence of heat treatment (T4 and T6) on milling performance, and the effects of speed, feed rate, and depth of cut. The output variables considered for this investigation are the surface roughness (Ra, Rz, Sa, and Sz), material removal rate (MRR), and cutting force. To optimize the milling parameters and achieve superior outcomes, the multi-objective optimization technique TOPSIS is used. At a feed rate of 150 mm/min, a spindle speed of 1500 rpm, and a depth of cut of 1 mm, the T4-treated sample exhibits a minimum surface roughness value of 0.0305 µm. The highest resultant force values of 96.4416 N and 176.1070 N for 200 °C and 225 °C T6-treated alloys are obtained by combining process parameters such as a spindle speed of 1500 rpm, a feed rate of 50 mm/min, and a depth of cut of 1.5 mm. Furthermore, the maximum closeness coefficient value is achieved by combining a spindle speed of 1000 to 1500 rpm, a feed rate of 150 mm/min, and a depth of cut of 0.5 mm to 1 mm. The closeness coefficient value is significantly influenced by the most significant process parameters, as indicated by the ANOVA results.

Hole quality geometrical measurement and surface roughness for α-Phase titanium alloy (α-Ti-6Al-4V) materials by using L-PBF (laser powder bed fusion) orthopedic implant application

This study examines the quality of circular-hole 3D-printed objects using laser powder bed fusion (L-PBF) on Ti-6Al-4V titanium alloy that typically used for orthopedic implants. Meanwhile measuring surface roughness and hole dimension deviations in AM specimens is very challenging. Thus, the specimens were printed with varying process parameters, followed by an L9 orthogonal array experiment, where parameters included laser power (LP) at 175, 185, and 195 W; scanning speed (SS) at 600, 900, and 1200 mm/s; and hatch distance (HD) at 70, 90, and 110 µm. Thus the, minimum surface roughness values are Ra 2.4 µm for the top surface and Ra 16.06 µm for the inside hole curve. Whereas the smallest hole deviations are 0.1102 mm for external and 0.2094 mm for internal diameters. Therefore, this analysis include FESEM, EDX, XRD, profilometry and stereomicroscopy. Where the best settings are LP 195 W, SS 900 mm/s, and HD 70 µm, producing well-fused, uniform α-phase Ti-6Al-4V specimens that are suitable for biomedical applications.

Fabrication and growth mechanism of Al-Si coatings deposited on Mo substrate by hot dip plating technology

The Al-Si coatings with a low surface roughness were deposited on Mo substrate via the hot-dip plating technology, and the effects of deposition parameters on the microstructure, phase composition and surface roughness were systematically investigated. The results show that the hot-dip Al-Si coating is consist of a Mo(Si, Al)2 inner layer and an Al(Si)-Mo(Si, Al)2 outer layer. The coating surface is composed of Si(70.21–92.66 at%)-Al alloy phase containing Mo (Si, Al)2 grains and Al(73.83–92.32 at%)-Si alloy phase. With the increase of deposition temperature and the extension of time, the average grain area of Mo (Si, Al)2 increases from 0.264 μm2 to 0.623 μm2. The coating surface becomes smoother with the increase of deposition temperature, while rougher with the time. The maximum and minimum average surface roughness(RSa) values of the coating are 0.847 and 0.431μm, respectively. The coating thickness increased with the increase of deposition temperature and times. When the deposition temperature is 1000 ℃, the thickness value of the Mo (Si, Al)2 layer of the coating increases in a parabolic law with deposition time, and the Kp(reaction rate constant) is 4.5 ×10−13 m2/s. The growth of coatings is essentially a process of depositing Al, Si elements in the form of Mo (Si, Al)2 intermetallic compounds on Mo substrate.

Effect of polymerization methods on surface roughness and hardness of commercially available self-curing acrylic resins: a comparative study

Purpose This paper aims to compare the surface roughness and hardness of three commercially available self-curing acrylic resins for dental use, under different polymerization conditions. Design/methodology/approach A comparative in vitro study was conducted using a convenience sample of 12 × 5 × 2 mm blocks with n = 40 for each material (Nic Tone, Arias Plus and Orthocryl®), with subgroups according to the polymerization method: conventional (C) and polymerization under ambient conditions (A). The surface roughness of the materials was measured using a profilometer; hardness was measured with a portable hardness tester. Additionally, surface morphology as well as particles size and morphology were evaluated with scanning electron microscopy. Findings There were significant differences in roughness and hardness values between the three self-curing acrylic resins (p < 0.05), as well as within each self-curing acrylic resin according to the polymerization method used (p < 0.05). The samples polymerized with the conventional method presented lower surface roughness and hardness values. Originality/value This study provides scientific evidence of values not provided by manufacturers in relation to the surface roughness and hardness of these materials, and all of them met the ideal minimum values of surface roughness, regardless of the polymerization technique used.

A comparative study on milling-induced surface roughness during milling of jute–epoxy and carbon–epoxy composites and optimization for better surface finish through Taguchi and RSM techniques

During the present experimentation, milling machining was performed on two different composites, namely carbon fiber-reinforced polymer composite and jute fiber-reinforced polymer composite, using a computer numerical control vertical machining center. The selected machining parameters were spindle speed (S), feed rate (FR), depth of cut (DOC), and flute number or cutting edge number (FN). The output parameter is the machined surface roughness (Ra). Analysis of variance was used to predict the percentage influence of each parameter on machining quality. The parameter feed rate exhibited a higher influence on the machined surface roughness, followed by spindle speed, flute number, and depth of cut in sequence. Similarly, while milling the carbon fiber composite, the feed rate had the highest influence, followed by the parameter flute number. As for the surface roughness, the feed rate had a greater effect, followed by the spindle speed. Under the same machining conditions, it was observed that the sequence of parameters influencing the jute composite and carbon composite changed in the case of cutting force generation, but the sequence of parameters was the same for both cases in terms of roughness. The outcome of the work confirmed that to achieve a smaller value of roughness in the milling of jute–epoxy composite, the optimum combination should be S = 3000 rpm, FR = 800 mm/min, DOC = 0.25 mm, and FN = 6. Similarly, to achieve the minimum surface roughness value in the milling of carbon–epoxy composite, the optimum combination of parameters should be S = 600 rpm, FR = 100 mm/min, DOC = 0.25, and FN = 6. The average roughness values obtained during the milling of jute–epoxy composite and carbon–epoxy composites are 6.685 and 3.08 μm, respectively. In this present work, it is proved that the optimum combination of parameters to get the minimum surface roughness and the amount of surface roughness produced during milling are highly influenced by the type of reinforced material. The graphs are prepared for the entire range of input parameters to identify the intermediate Ra value at any input value without the use of software.

Optimization of Electrical Discharge Machining Process by Metaheuristic Algorithms

Because of its versatility and ability to work with difficult materials, Electrical Discharge Machining (EDM) has become an essential tool in many different industries. It can produce precise shapes and intricate details. EDM has transformed fabrication processes in a variety of industries, including aerospace and electronics, medical implants and surgical instruments, and the shaping of small components. Its capacity to machine undercuts and deep cavities with little material removal makes it ideal for producing complex geometries that would be challenging or impossible to accomplish with conventional machining techniques. Several attempts have been carried out to solve the optimization problem involved in the EDM process. This paper emphasizes optimizing the EDM process using three metaheuristic algorithms: Glowworm Swarm Optimization (GSO), Grey Wolf Optimizer (GWO), and Whale Optimization Algorithm (WOA). The study's outcome showed that the GWO algorithm outperformed the GSO and WOA algorithms in solving the EDM optimization problem and achieved the minimum surface roughness value of 1.7593µm.

Parametric study of WEDM of titanium grade 12 using RSM and desirability approach

The present experimental study aims to scrutinize the effect of different process parameters on the material removal rate (MRR) and surface roughness (SR) of titanium grade 12 alloy during wire electro-discharge machining (WEDM) using response surface methodology. Four parameters (pulse-on time, pulse-off time, wire feed and gap voltage) and three levels of each selected variable are considered to conduct the experimental work. Depending on experimental results, a mathematical model is generated for both MRR and SR. An analysis of variance (Anova) study is performed to find significant process parameters. The Anova results show that the developed models for both MRR and SR are significant, and pulse-on time is found to be the most significant parameter. Additionally, the desirability approach is used to scrutinize the single-objective and multi-objective criteria of response variables. The desirability functions for all of the cases are found to be 1. The maximum MRR is observed to be 12.4845 mm3/s, while the minimum value of SR is found to be 1.4911 μm. For multi-objective optimization, the maximum value of MRR and the minimum value of SR are obtained as 12.0942 mm3/min and 1.7167 μm, respectively. Finally, the surface morphology of the machined surfaces is examined using scanning electron microscopy micrographs.

The new Iridium-Hafnium-Aluminum alloy thin films with excellent mechanical properties and oxidation resistance

Improving oxidation resistance has long been a challenge for hot end components in high temperature environments. We have fabricated a series of IraHfbAlc (at. %) alloy thin films by multi-targeted direct current magnetron sputtering (DC-MS) and have thoroughly investigated the microscopic mechanism of the films. More importantly, we for the first time prepared IraHfbAlc alloy thin films with a preferred (111) orientation substitution solid solution, which exhibits excellent mechanical properties and oxidation resistance. The minimum surface roughness (Ra) value of the IraHfbAlc alloy films was 0.7 nm, while the maximum hardness (H) and elastic modulus (E) exceeded 20 GPa and 330 GPa, respectively. The oxidized volatility of the Ir in the films was only 0.11 μm/h at 1300 °C (lower than most previously reported values, such as 0.5 μm/h), which greatly improved the lifetime of the film. Confirmation that lattice distortion induces the refinement of crystal-like order (CLO) in thin films, and solves the mystery of enhanced oxidation resistance. The findings provide important insights into the design of Ir-containing alloy coatings and offer new ideas in the field of high-temperature protection.

Investigation of machining rate and surface roughness in wire EDM of Al6063/WC/ZrO2 composite using response surface methodology

The aim of the current work is to explore the machinability behavior of Al6063/WC/ZrO2 metal matrix composites (MMC) produced through a stir casting process through wire electrical discharge machining (WEDM) process. In order to examine the effects of process parameters such as voltage (V), pulse on time (Ton) and pulse off time (Toff) on material removal rate (MRR) and surface roughness (SR), the experiments were conducted by adapting Response Surface Methodology (RSM) in conjunction with the central composite design (CCD). A second-order regression model has been developed to predict the response parameters and an analysis of variance (ANOVA) was performed to validate the significance of the models. Using the desirability function approach, the parameters were set for the highest MRR and the minimum SR value. The prediction was within a tolerable average error range. A total of 19 sets of tests were developed to obtain six possible solutions. The most suitable solution among these six has been found by a confirmatory experiment. The results indicate that voltage and its interactions have significantly affected both the responses than Ton and Toff. Overall, it can be said that the study of the Al6063/WC/ZrO2 MMCs using WEDM process parameters demonstrated improved casting and machining qualities.

Influence of surface polishing on the degradation behavior of biodegradable Magnesium alloy

Mechanical polishing can significantly improve the surface integrity of Mg alloys to reduce the corrosion rate (CR) by minimizing the galvanic corrosion sites. In this study, an emery-polishing attachment on a lathe machine has been used for surface polishing of as-turned cylindrical ZM21 Mg alloy. Using Taguchi’s L9 orthogonal array, three process variables with three levels were investigated and optimized for minimum surface roughness (Ra and Rz values) of Mg-alloy samples. The minimum surface roughness values of Ra; 195 nm and Rz; 1481 nm were obtained corresponding to emery paper (EP) grade; 2000, rotational speed; 250 rpm, and polishing time; 2 min. An in-vitro immersion study was conducted in simulated body fluid (SBF) for up to 28 days to investigate the degradation behavior of as-turned and as-polished Mg alloy samples. In-vitro study showed that the as-turned samples (surface roughness; Ra: 640 nm, Rz: 4640 nm) had a higher degradation rate (CR: 3.9 mm year−1 after 28 days) with a higher volume of H2 evolution rate, whereas the polished sample with the minimum surface roughness (Ra: 195 nm, Rz: 1481 nm) exhibited lower weight loss, H2 release rate, degradation rate (CR: 0.95 mm year−1 after 28 days) and minimum loss of mechanical strength. Based on the present study, polishing is recommended as a secondary operation after machining of Mg alloy to reduce the corrosion rate for biodegradable implant applications.

Analisis Pengaruh Variasi Kecepatan Spindel Dan Feeding Terhadap Nilai Kekasaran Permukaan Proses Finishing Bubut CNC

In the industrial sector, technological progress has experienced very rapid development. So that the manufacturing industry is required to be able to produce quality products and a high level of accuracy with fast processing. One machine that can meet these demands is a CNC lathe, where a CNC lathe is a machine that is controlled using a computer system in its operation. In the machining process of CNC lathes, the level of surface roughness of the machining material is of great concern, because the lower the surface roughness value, the better the quality of the product. Therefore, the aim of this study was to obtain a low surface roughness value using a finishing cutting edge. The material used is AISI 1045 steel which is turned using a MORI SEIKI SL-25 CNC machine. The parameters used are spindle speed and feeding. The research method used was the Taguchi method with an orthogonal matrix L9(32) experimental design and 3 replications were carried out to reduce large deviations. The result of this research is to obtain a combination of parameters that produce minimum surface roughness values, namely spindle speed of 1804 rpm and feeding of 0.1 mm/put. And the parameter that has the greatest effect on the value of roughness is feeding with a difference of 16.029 and the one that has the least effect on the value of surface roughness is spindle speed with a difference of 1.384.

Tool wear and surface integrity in liquid nitrogen clean cutting of cobalt-based superalloy GH605 with AlTiN coated tools

The tool wear is severe and the machined surface quality is low in dry cutting of cobalt-based superalloy. The traditional coolant is harmful to the environment and not in line with sustainable development. The liquid nitrogen (LN2) clean cutting of cobalt-based superalloy GH605 using AlTiN coated tools is proposed in this work. The tool wear mechanism and the machined surface integrity are investigated. The results show that, with the decrease of LN2 injection temperature, the sharp wear stage of the tool can be delayed. The injection temperature directly affects the tool life. Compared with dry cutting, the tool life is increased by 42.5% at LN2 injection of −190 °C. Under the lower liquid nitrogen condition, the coating peeling is reduced on the rake face. The decrease of LN2 injection temperature can effectively reduce the damaged area of the flank face and inhibit the oxidation wear. The injection temperature between −30 °C and −150 °C can significantly reduce the surface roughness. The minimum surface roughness value at the injection temperature of −90 °C is 0.486 μm, which is 39.4% lower than that at dry cutting condition. When the LN2 injection temperature is below −90 °C, the thickness of the white layer is less than half of that in dry cutting condition. The hardness of the machined surface is enhanced and the residual stress is reduced at injection temperature below −150 °C. This work demonstrates the possibility of improving the machinability of cobalt-based superalloy by optimizing the LN2 injection temperature.

Optimization of surface roughness parameters in Hybrid-Chemo Magnetorheological Finishing (HC-MRF) process using Response Surface Methodology and Genetic Algorithm

Hybrid Chemo-Magnetorheological Finishing ( HC-MRF) process is an advanced surface finishing process that utilizes the interaction of Magnetorheological Finishing and chemical etching to reduce the surface roughness of the cemented carbide cutting tools. Herein, Murakami’s reagent is used as a Magnetorheological (MR) fluid carrier medium to trigger chemical etching and mechanical abrasion. The synergic action reduces surface finishing time and increases process efficiency. However, optimizing process parameters during the HC-MRF process is required to improve process efficiency further. Response Surface Methodology ( RSM) is used to develop the regression model to study the impact of process parameters (i.e. spindle speed, feed rate, and vol.% of Murakami’s reagent in MR fluid) on the surface quality. Three surface roughness parameters, namely average surface roughness ( Ra), skewness ( Rsk), and kurtosis ( Rk), are opted to analyze the surface characteristics of the polished surface. Furthermore, optimization is performed with the help of a Genetic Algorithm ( GA) to achieve the best surface quality following input parameters. The surface roughness ( Ra) is reduced by 88.97% as the initial Ra value decreases to 34.50 nm from 312.87 nm after the HC-MRF process. The results obtained from RSM and GA are in good agreement with the experimental results. The optimum value of feed rate, spindle speed, and vol.% of Murakami’s reagent in the MR fluid while achieving minimum surface roughness value (i.e. 31.26 nm) through GA are 1.2 mm/min, 23 rpm, and 53%, respectively. The measured kurtosis ( Rku) value of 0.64 at the optimum process parameter condition represents flat peaks on the surface roughness irregularities of the polished surface. Similarly, a skewness ( Rsk) value of 1.46 signifies that the number of peaks is higher than the number of valleys on the polished surface. Furthermore, it is observed that the Vol.% of Murakami’s reagent in MR fluid is the most significant process parameter compared with other parameters among all responses.

Investigation on the effective factor calculation of electropolishing using full factorial design and mechanism model by microscopic analysis for super austenitic stainless steel

This investigation is to calculate the effective factors of the electropolishing by using the full factorial design for UNS N08367. In addition, based on the calculated effective factors, the electropolishing mechanism model was researched on 3D microscopy and scanning electron microscopy analysis. The parameters were selected as electrolyte composition ratio, electropolishing process time and applied current density. Calculation of effective factors was performed through analysis of variance (ANOVA). As a result of ANOVA, it was observed that the electrolyte composition ratio had the greatest effect on surface planarization. As a result of surface analysis after electropolishing, the maximum height difference is about 54 times. Also, the minimum value of surface roughness after electropolishing was 0.129 μm, which was improved by more than 70% compared to mechanical polishing. As a result of all analysis, it was most flat to perform electropolishing with a sulfuric acid and phosphoric acid ratio of 3:7, 300 mA/cm2 and 5 min.

Properties of Ni-Al2O3 composite coating by laser-assisted pulse electrodeposition.

To study the influence of laser process parameters on the surface properties of the coating, N i-A l 2 O 3 composite coatings on 304 stainless-steel sheets with laser-assisted pulsed electrodeposition was proposed in this paper. Laser single pulse energy and scanning speed were selected as research factors. Single-factor experiments were performed to investigate the effect of various factors on the surface morphology, particle mass fraction, microhardness, surface roughness, and corrosion resistance of the composite coating. The experimental results show that the surface properties of the composite coating first increase and then decrease with increasing laser single pulse energy. When the laser single pulse energy is 11µJ, the minimum surface roughness value is 0.380µm with a smooth and uniform coating surface and the best surface morphology. Moreover, as the scanning speed increases, the corrosion resistance of the composite coating initially increases and then decreases. The corrosion resistance of the composite coatings is best with a scanning speed of 1000mm/s. When the scanning speed was 1500mm/s, the particle mass fraction in the coating reached a maximum of 1.984%; meanwhile, the highest hardness of the composite coating was obtained with the value of 476.38 HV.

Tribological characterizations and numerical simulations of thermoplastic composites in pin-on-disc configuration

The tribological characterizations and numerical simulations of filler reinforced polymeric composites for sliding wear in pin on disc configurations was performed using the finite element simulations. This paper aims to perform the numerical simulation of the deformation and strain in sliding wear. The evaluations for the deformation and strain are carried out by following the Archad’s linear wear law. The study assumes a uniform pressure distribution during simulation. The tribological behaviours of the polymeric composites was found to be non-linear. The results of the tribological characterization found the minimum values of surface roughness (Ra) and coefficient of friction to 0.6643 µm and 0.081 respectively. The values of friction forces for the developed composites were found to increase with the applied load. The density and hardened were found in the ranges of 0.8404–1.5304 (g/cm3), and 4.6–15.8 HV respectively. Moreover, the values for density and hardness were found to improve with the incorporation of sand particles as fillers. The study showed that the tribological performances of the polymeric composite increases with reinforcement. The study was found significant to predict the deformation and strain of polymeric composites without lasting and usually expensive experiments.

Prediction and Optimization of Surface Roughness for Laser-Assisted Machining SiC Ceramics Based on Improved Support Vector Regression.

In this paper, the surface roughness of SiC ceramics was investigated in laser-assisted machining (LAM) processes; machine learning was used to predict surface roughness and to optimize the process parameters, and therefore, to ultimately improve the surface quality of a workpiece and obtain excellent serviceability. First, single-factor turning experiments were carried out on SiC ceramics using LAM according to the material removal mechanism to investigate the variation trend of the effects of different laser powers, rotational speeds, feed rates, and cutting depths on surface roughness. Then, laser power, rotational speed, feed rate and cutting depth were selected as the four factors, and the surface roughness was used as the target value for the orthogonal experiments. The results of the single-factor experiments and the orthogonal experiments were combined to construct a prediction model based on the combination of the grey wolf optimization (GWO) algorithm and support vector regression (SVR). The coefficient of determination (R2) of the optimized prediction model reached 0.98676 with an average relative error of less than 2.624%. Finally, the GWO algorithm was used to optimize the global parameters of the prediction model again, and the optimal combination of process parameters was determined and verified by experiments. The actual minimum surface roughness (Ra) value was 0.418 μm, and the relative error was less than 1.91% as compared with the predicted value of the model. Therefore, the prediction model based on GWO-SVR can achieve accurate prediction of the surface roughness of SiC ceramics in LAM and can obtain the optimum surface roughness using parameter optimization.

Parametric Studies on Finishing of AZ31B Magnesium Alloy with Al2O3 Magnetic Abrasives Prepared by Combining Plasma Molten Metal Powder with Sprayed Abrasive Powder

High-performance iron-based Al2O3 magnetic abrasive powder (MAP) prepared by combining plasma molten metal powder with sprayed abrasive powder is used for magnetic abrasive finishing (MAF) of AZ31B magnesium alloy to remove surface defects such as creases, cracks, scratches, and pits generated during the manufacturing process of the workpiece, and to reduce surface roughness and improve its wear and corrosion resistance. In order to solve the problem of magnetic abrasive powder splash in the MAF process, the force analysis of the MAP in the processing area is conducted, and a composite magnetic pole processing device was designed and simulated to compare the effects of both devices on MAF, confirming the feasibility of composite magnetic pole grinding. Then, experiments have been designed using Response Surface Methodology (RSM) to investigate the effect of four factors-magnetic pole rotation speed, grinding gap, magnetic pole feed rate, magnetic abrasive filling quantity-on surface roughness and the interactions between them. The minimum surface roughness value that can be obtained is used as the index for parameter optimization, and the optimized parameters are used for experiments, and the results show that the established surface roughness model has good predictive ability.

Evaluation of surface characterization and mechanical features of resin-matrix ceramics before and after different surface treatments

Statement of problemSurface treatments (STs) required for micromechanical interlocking can lead to alterations in the surface characterization and mechanical features of the resin-matrix ceramics (RMCs), which may jeopardize the long-term outcome of an indirect restoration. However, evidence on this issue is lacking. PurposeThe purpose of this in vitro study was to assess the influence of different STs on the surface roughness (SR), water contact angle (WCA), and flexural strength (FS) of RMCs. Material and methodsTwo hundred rectangular plates (12×14×1 mm) were prepared from 5 different RMC ingots, including a polymer-infiltrated ceramic network (Vita Enamic [VE]), 2 resin nanoceramics (Lava Ultimate [LU], Grandio Blocks [GB]), a flexible nanoparticle-filled resin (GC Cerasmart [GC]), and a reinforced composite resin (Brilliant Crios [BC]). Plates of each RMC group were further divided into 4 subgroups according to the ST applied: Control, no treatment (C); airborne-particle abrasion with aluminum oxide particles (APA); 2W- and 3W-Er,Cr:YSGG laser irradiations (LI2W, LI3W) (n=10 per ST). The SR (Ra) of each plate was recorded with a contact profilometer. WCAs (θ) of distilled water on the plates were determined by using the sessile-drop method. The FS (MPa) of each plate was measured with a universal testing machine. Data acquired for SR, WCA, and FS were statistically analyzed (α=.05). Weibull statistics were also conducted to determine the reliability of each material. ResultsThe 2-way ANOVA showed that SR, WCA, and FS values were significantly influenced not only by all tested variables but also by their interaction terms (P<.001). All STs significantly increased the SR values (P<.05). Maximum and minimum SR values were recorded in GC-LI3W (7.06 ±0.16) and GC-C (0.07 ±0.02) groups. After STs, WCA values significantly diminished (P<.05). Maximum and minimum WCA values were recorded in LU-C (61.74 ±2.45) and VE-APA (40.38 ±1.56) groups. All STs significantly reduced the FS values (P<.05). The upper and lower FS bounds were 140.7 ±17.07 and 60.66 ±6.31, respectively, set by VG-C and GC-APA. Weibull distribution indicated that the untreated groups presented the highest m values. Among the treated groups, BC-LI3W demonstrated superior reliability (m=14.04). ConclusionsAPA for LU, LI2W for VG and BC, and LI3W for GC and VE can be preferred. Although APA increased the SR and provided more wettable surfaces, it caused considerable loss of FS. Therefore, LI can be recommended as a safer ST for RMCs.