بحوث سكوبس — علاء محمد حسين ويس

Aluminum-siliconalloy castings can benefit from friction stir processing (FSP) locally. In this work, the result of FSP on sand castings of aluminum-silicon cast alloys4%, 12% and 15% Siw as investigated. The influences of different processing parameters on the microstructure and mechanical properties include the rotation speed (560,710, 900 rpm) and the transverse speed (86, 189, 393) mm/min. Various tests of mechanical, including impact, micro hardness and tensile tests, have been carried out. An infrared (IR) camera fitted by software to evaluate the image of thermal fort he treatment zone and ascertain the temperature at particular locations was used to investigate the temperature distribution. Results suggest that increasing rotational speed leads to an increase in heat generation, whereas increasing transverse speed leads to a decrease in heat generation. Hardness measurements were carried out throughout the entire process zone, Tests for tensile strength were conducted at room temperature., and FSP resulted in very little change in the hardness while significantly improving its properties of tensile and impact. The cast aluminum-silicon alloys’ microstructure. significantly improved after FSP. Nevertheless, differences in microstructure were noted throughout the processed zone, with the advancing side typically having a more refined and distributed microstructure than the retreating side.the best speeds (rotating speed of tool (710 rpm) and speed of transverse (189 mm/min) that gave best results. © 2025 Jordan Journal of Mechanical and Industrial Engineering. All rights reserved

Here in, we report the synthesis of 1,4-Bis(pyridin-1-ium)benzene trifluoroacetate coordinated to chloropropyl functionalized SiO2-nano-NiFe2O4 (BPBTCSF). Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), elemental mapping analysis, Brunauer-Emmett-Teller (BET), thermal gravimetric analysis (TGA), vibrating-sample magnetometry (VSM) and X-ray diffraction (XRD) techniques characterized the framework of this catalyst. The catalytic activity of this nano-composite was then examined in the one-pot four-component reaction of 2-thiobarbituric acid, NH4OAc, and aldehyde for synthesis of pyrido[2,3-d:6,5-d']dipyrimidines under optimal conditions (5 mg of BPBTCSF, H2O, 25 °C). BPBTCSF exhibits benefits as a heterogeneous catalyst, such as exciting performance in the production of derivatives (2 to 5 min, 90 % to 98 %), six times reproducibility with a slight decrease in catalytic activity, the simultaneous presence of acidic and basic sites (Hydrogen attached to the electronegative nitrogen atom and CF3COOˉ, respectively), convenient purification and separation from the reaction mixture. © 2024 Elsevier B.V.

The objective of this study was to statistically analyze the effects of plasma nitriding using response surface methodology(RSM). The RSM, which is dependent on a core composite construction, was used to study the effects of variables like percentage nitrogen / hydrogen flow, deposition time, deposition temperature, and CNT concentration, on wear and corrosion behavior for electroless (Nickel-Boron-CNT)coating for low steel alloy. The results for plasma samples with different CNT concentration (0%, 0.35%, 0.7%) showed the effects of deposition temperature and time as well as percent hydrogen/nitrogen ratio on the corrosion rate. The results of microhardness showed that the highest microhardness value of (1200 HV) was achieved for the Ni-B coating containing 0.35 g/L CNT after plasma nitriding. The optimum design point for plasma nitriding (low wear rate, low friction coefficient, and extreme hardness) was achieved with a desirability of 0.95 at a temperature of 413.03°C for 4h with H2/N2 percentage ratio of %54.17/%45.83 and a concentration of 0.35% CNT, whereas the lowest corrosion rate was achieved at a temperature of 387.78°C for 2.53 h, with H2/N2 percentage ratio of 52.74/47.26 and at a concentration of 0.35g/l CNT. This effect was amplified by raising the deposition temperature between 400 0C and 450 0C. Excellent corrosion resistance is exhibited by the Ni-B-CNT composite coating, and this resistance greatly increases as the concentration of CNTs increases. Excessive CNT deposition leads to agglomeration, harming the coating and reducing its corrosion resistance. © 2025 Jordan Journal of Mechanical and Industrial Engineering. All rights reserved

Biomass is a renewable source of energy obtained from biological materials. Gasification technology is commonly used to produce hydrogen (H2) from biomass. This method is based on the partial oxidation of the input materials and their conversion into synthetic gas. After gasification, the biomass is converted into a gas consisting of H2, carbon monoxide (CO), carbon dioxide (CO2), and other compounds. This research investigates the number of H2 molecules (n(H2)) and CO molecules (n(CO)) in the basic structure at a temperature and pressure of 1 bar and 1800 K. Additionally, the effect of initial pressure (IP) changes on the n(H2) and n(CO) produced with a 10 % volume fraction of platinum (Pt) catalyst was evaluated using molecular dynamics (MD) simulation. The results demonstrate that the produced n(H2) and n(CO) increase from 559 to 146 to 586 and 165, increasing the Pt nanocatalyst ratio from 1 % to 10 %. Furthermore, the n(H2) and n(CO) increase from 586 to 165 to 598 and 175, respectively, by increasing the IP from 1 to 5 bar. Also, the results reveal that the combustion efficiency (CE) increases from 62 % to 66 % with increasing IP from 1 to 5 bar. The application of this research is to study the production of hydrogen and carbon monoxide from biomass using gasification technology. This information can be useful for improving the efficiency of biomass gasification for hydrogen production. © 2023 Hydrogen Energy Publications LLC

Today, the emergence of composite structures can be considered a huge transformation on an industrial scale, especially in the transportation industry. Among all the structures made by the composite process, aluminum-based composites (AMMCs) are particularly popular both in the scientific and industrial fields. These structures are very light in weight and, at the same time, have significant strength. The ability to work with the machine in these structures is very high, and their plastic deformation is so high that they can be used in different industry sectors. Today, various methods are used to induce plastic deformation in aluminum-based composites (AMMCs). One of these methods is called aggregate accumulative press bonding (APB). The advantage of this method compared to other methods is that this method can create a homogeneous nanocomposite with ultra-fine grains. In the present study, the investigation of mechanical properties (MP's) of AA5083/5%SiC bulk composites fabricated via APB vs. pressing temperature (Temp) was conducted. All primary composite samples were fabricated via the stir-casting process (SCP). APB process was done on composite samples as a supplementary process. Finally, the effect of pressing Temp on the MP and microstructural properties (MSP) was investigated. The pressing Temp was varied between the ambient Temp's up to T = 300 °C. The MP were measured in this study by the Vickers micro-hardness (VMH) test, tensile test, and scanning electron microscopy (SEM). It was realized that the pressing Temp has a prominent effect on the MS and MP of fabricated 400°C. Samples fabricated at the ambient Temp have low ductility and high strength while for samples fabricated at T = 300 °C, the elongation and toughness values were higher than others. The TS of samples after 2 steps of APB at T = 200°C is 1.31 times more than that of fabricated at T = 300°C. Elongation was reduced sharply to 1.8% after the two steps at the ambient Temp, while it was 21% for the annealed AA5083. © 2024 The Author(s)

This numerical research used innovative fins that mix parallelogram and rectangular fins to look at the melting of the phase change material (PCM). This paper analyzed, in 2D and using a numerical solution, the melting behavior of several fin models with various angles under constant flux circumstances in a rectangular cavity. The left wall of the storage was subjected to a heat flux of 2500 W/m2. The major objective of the current research was to introduce fins with novel models, which are a mix of rectangular and parallelogram fins, in order to further enhance the melting performance of PCM. For this purpose, the effect of different fin models (with different angles:15°, 30°, 45°, 60°, 75°, and 90°) in the condition of constant heat flux in a rectangular cavity was studied. The results show that among various geometries studied by fin, proposed geometry of model E was selected among the models. Changing the fin model reduces the melting time, which led to a higher energy charging rate. Moreover, by examining different melting angles, the maximum and minimum melting times occurred at 0° and 60°, respectively. The heat flux had an inverse relationship with the melting time; the higher the heat flux, the shorter the melting time. E model with an angle of 60° had the best performance. Because it had reached complete melting in the shortest time, in this model, after 52.25 min, the PCM completely melts. The stored energy for PCM at 60° was less than other angles, and equal to 236.04 MJ. The average power for angles from 15° to 90° was almost equal, and at angle 0°, it was less than other angles. © 2023

In this study, the mechanism of diazinon adsorption on single-walled carbon nanotubes (SWNTs), as well as multi-walled carbon nanotubes (MWNTs), was investigated using molecular modelling. Determination of the lowest energy sites of different types of carbon nanotubes (CNTs) was demonstrated. The adsorption site locator module was used for this purpose. It was found that the 5-walled CNTs are the best MWNTs for diazinon elimination from water due to their higher interactions with diazinon. In addition, the adsorption mechanism in SWNT and MWNTs was determined to be wholly adsorption on the lateral surface. It is because the geometrical size of diazinon molecules is larger than the inner diameter of SWNT and MWNTs. Furthermore, the contribution of diazinon adsorption on the 5-wall MWNTs was the highest, for the lowest diazinon concentration in the mixture. © 2023 The Authors

The aims of this work to study the hardness, wear resistance and corrosion resistance of as-plated and heat treatment of Ni-Co-P-B4C electroless coatings. Ni-Co-P and Ni-Co-P-B4C composite were coated on substrate (AISI 4140 steel) with different concentration for B4C (0.3 g/l, 0.5 g/l and 0.7 g/l) in bath of an electroless coating. After the coating finish, the samples were annealed at (400 °C, for 1h). The behavior of wear for the composite coatings was calculated with using a pin on disk method at load of (10 N). An alkaline bath having nickel chloride as the source of nickels, Sodium hypophosphite as the reducing agent, Cobalt Chloride as the source of Cobalt and B4C was used to prepare the electroless Ni-Co-P-B4C coatings. The specimens were characterized with XRD, XRD, EDS, FESEM, surface roughness and microhardness. Results of microhardness obtained the maximum hardness at 1020 HV for Ni-Co-P heat treated sample. By comparing results wear test for Ni-Co-P with Ni-Co-P-B4C and Ni-P. An annealed Ni-Co-P had the lower specific wear rate in comparison with the other specimens because of many reasons such as lowest coefficient of friction, larger microhardness, finer grain size and excellent homogenous distribution of Ni3P and Ni particles. Compared to the Ni-P, Ni-Co-P and Ni-Co-P-B4C coating, resistance of corrosion of Ni-Co-P composite coating are better. The adding of B4C made the coating denser, and agglomeration that occurs is very unfavorable to coating, resulting in potential of corrosion of the composite coating becoming negative gradually, lead resistance of corrosion of the composite coating becomes worse. © 2023 Author(s).

The aim of work a statistical study of the effects of plasma nitriding parameters such as deposition temperature, deposition time, concentration of CNT and percentage nitrogen and hydrogen flow on the wear behavior of electroless coating (Ni-B and Ni-B-CNT) on AISI 4340 steel was examined using response surface methodology (RSM) method based on a central composite design. Results indicated the effects for temperature of the deposition and the deposition time on rate of the wear for plasma nitriding of samples in the constant concentration CNT (0.35%) and percentage hydrogen/nitrogen ratio(50%). The rate of the wear for samples is decrement by an increment of deposition time and an increase in the temperature from range 350 °C - 400 °C and increased by a another increment in temperature of the deposition from range 400 °C - 450 °C. Rate of wear for the materials depends not just into condition of wear test, but also with several properties of material and features as topography, hardness and friction coefficient. © 2023 Author(s).

Objective The aim of this study was to measure the oral hygiene problem (dental plaque and measure the severity and prevalence of gingival disease) and enamel defects among 22-23 years old students of dentistry college in Babylon Iraq. Methods A representative sample included in this study consisted of 300 students, they were selected randomly. Dental plaque was measured using Silness and Loe (1964) plaque index. The gingival health condition was measured using Loe and Silness (1963) gingival index, while enamel anomalies were measured following the criteria of WHO. Results The mean value of plaque index of total sample, for females was 1.11 and male is 1.47 the mean value of gingival index of female was 1.027 and male was 1.30 with statistically, no significant difference (P value >0.05), the enamel defect prevalence was 29%. The most prevalent type of enamel anomalies was demarcated opacity (12%) followed by diffused opacity (10%). Conclusion Demarcated opacity was common type of enamel defects. The demarcated opacity is a defect include change in the translucency and has a clear boundary with the adjacent normal enamel. The color may be white, cream, brown or yellow. © 2023 Pakistan Association of Dermatologists. All rights reserved.

In this study, the molecular dynamics (MD) simulation was used to evaluate the role of imprinting temperature and the mold-cavity geometry on the imprinted Ni-P metallic glass (MG) films. Considering the outcomes of simulation, it was found that the tip-like and groove patterns showed different filling time for the imprinting process. At room temperature (300 K), the plastic deformation in the tip-like pattern was in a ring shape enclosing the mold, while the plastic deformation in the groove-pattern geometry was mainly localized at the wall of mold. Moreover, it was determined that the imprinting at high temperature (700 K) led to the shortening of pattern filling time and the decrease of loading force in both geometries. The strain concentration and localized plastic deformation were also removed in the high-temperature imprinting process. On the other hand, the unloading process at room temperature (300 K) improved the imprinting quality due to the lower elastic recovery. © 2023 Tri Widodo Besar Riyadi et al.

Study wear resistance for heat treatment of Ni-B-CNT electroless coatings. Different concentrations for CNT (0 ,0.35 and 0.7 g/l Ni-B-CNT composite coatings deposition on 4340 steel. After the procedure of coating, all samples were heat treatment. The test wear of a coating was valued with pin on disk technique. Preparation of Ni-B-CNT electroless coatings are with using nickel chloride in alkaline bath, borohydride and Multi walled carbon nanotubes. characterization with FESEM, micro hardness, XRD and surface roughness. Study for surfaces of worn with EDS and FESEM. Micro hardness results are show that the larger hardness1010 HV is gained by heat treatment for coating (Ni-B- 0.35 g/L CNT) because of concentration CNT caused structure conversion for coating Ni-B from amorphous to crystalline. Also, CNT prevent maximum heat production and decrease of the friction coefficient during test wear. CNT aggregation was noted result the presence for more particles (Ni-B - 0.7g/l CNT) that occur create roughness and also lead to increase in rate of wear because of big particles with weakly joined in matrix of Ni. © 2023 Trans Tech Publications Ltd, Switzerland.

In this study, Ni–P–Fe2O3 composite was deposited on AISI 4140 steel using different concentrations of Fe2O3 ranging from 0.1 to 0.5 gr/lit in an electroless bath. The phase analysis and surface morphology of the samples were characterized using X-ray diffraction and FESEM. The corrosion behavior of the coated samples was investigated in a 3.5 wt. % NaCl solution through potentiodynamic polarization. The results of the potentiodynamic test show that adding Fe2O3 into an electroless bath facilitates the formation of the passive layer. The results show that the coating created at a thickness of (10-16µm) had the highest corrosion resistance compared to other coated and non-coated samples. Furthermore, the results of the friction coefficients of the samples produced by powder metallurgy have decreased because Fe2O3 particles led to a decrease in grain size in the heat treatment of specimens and prevented excessive heat generation during the wear test; thus, the friction coefficient decreased during the test. © Jasim et al. 2023 Open Access.

Using the rolling process, it is possible to induce multiple shear bands in the microstructure of metallic glasses (MGs) and improve the overall plasticity in the subsequent mechanical loadings. Hence, it is crucial to understand the mechanism of shear banding and plastic deformation under the rolling process. In this work, molecular dynamics (MD) simulation was applied to evaluate the formation and generation of shear bands in a CuZr MG under cold- and hot-rolling processes. Based on the results, it is found that the shear bands are formed with secondary branches in the cold rolling, while the shear events are scattered in the bulk of material in the hot rolling. Considering Voronoi analysis, it is revealed that the hot rolling is accompanied by the recovery of crystalline-like clusters provided that rolling process continues for subsequent passes. On the other hand, the cold-rolled sample shows a stable behavior in the evolution of crystalline-like clusters; however, the population of main icosahedral polyhedrons decreases in the system. © 2023 Ramaswamy Sivaraman et al.

Friction stir welding is a comparatively new method for assembly of metals. Study similar alloy of AA 2040were done by FSW process and also study effects behavior of FSW on some mechanical properties (tensile, impact energy and microhardness). Studied were parameters (FSW) like speeds of transverse (116,189 mm/min) and speeds of rotational (450,560 rpm) which effects on mechanical micro structure and properties. Indicates of results of the tensile test that which increase tensile strength (316 MPa)by decreases speeds of rotational and increases of welding speeds, at parameters of the welding (560 rpm and 116 mm/min) with 71% efficiency. FSW caused small differences to micro hardness of the material. Enhancement energy absorbed from (2.5)J at substrate alloy with compared(3.7)J in FSW. The microstructure was greatly refined, after FSW. © 2023 Author(s).

The aims of the work to study the resistance of corrosion and the hardness of plasma-nitrating and heat treatment of coatings with electroless Ni-B-CNT. Various concentration of CNT range, (0, 0.35 and 0.7)g/L in Ni-B-CNT composite was deposit on 4340 steel in electroless immersion. Following the procedure of plating, every samples were plasma-nitrating in atmosphere consist of 50% N2-50% H2, about (400°C), at (2.5h) were compared with those of annealed one. The electrodes Ni-B-CNT coatings were prepared by using nickel chloride as source for nickel, borohydride act as reducing agent and used (MWCNT). Results of micro hardness was show that the higher hardness of (1250HV) was achieved for Ni-B-0.35g/L CNT plasma-nitrating formula whereas the greatest hardness of (1010HV)was become for sample of Ni-B-0.35g/L CNT heat treated. Resistance of corrosion of Ni-B-CNT composite coating are better, and they become much better with the increase of the CNT concentration. Increase too much CNT deposited on the substrate, leading to a high region of CNT and agglomeration that occur is very unfavorable to coating, lead resistance of the corrosion of the composite coating becomes worse. Also, compared between heat treatment and plasma-nitride, results of that resistance of the corrosion with plasma-nitriding is better. © TJPRC Pvt. Ltd.

The basic aim to study wear resistance and hardness of heat treatment of coatings with electroless Ni-P-CNT. Various concentration of CNTs range, 0, 0.1, 0.2 and 0.4 g/L in Ni-P-CNT composite was deposit on low alloy steel in electroless immersion. The Ni-P-CNT electroless coatings were prepared by using nickel chloride as a source for nickel in alkaline bath and used CNT. The formulas were characterized with means of EDS, SEM, micro hardness, surface roughness and wear resistance measurements. The results of that micro hardness showed higher hardness (560 HV) was achieved for heat-treated sample (Ni-B-0.1g/l CNT). The results enhance the concentration of CNTs caused structure of as-coated Ni- P conversion from amorphous to crystalline. Compared to the Ni-P coating, wear resistance of composite coating (Ni-PCNT) is better, and they become much better with the increase of CNT concentration. The adding of CNT makes the coating denser and the presence of CNT makes the size of grain to decrease in accordance with the heat treated formulae, but too much CNT deposited on the substrate leads to a high region of the CNT wrapped together. and agglomeration that occurs is very unfavorable to coating, resulting in lead wear resistance of the composite coating and becomes worse. © TJPRC Pvt. Ltd.

The basic aim is to study the resistance of corrosion and hardness of heat treatment of coatings with electro-less NiP-CNT. Various concentration of CNTs ranging, 0, 0.1, 0.2 and 0.4g/L in Ni-P-CNT composite was deposited on low alloy steel in electro-less immersion. The Ni-P-CNT electro-less coatings were prepared by using nickel chloride as a source for nickel in the alkaline bath and used CNT. The formulas were characterized with means of EDS, SEM, micro hardness, surface roughness and corrosion measurements. Results of the micro hardness show that hardness higher (560 HV) was achieved for sample (Ni-B-0.1g/l CNT) heat treated. Results enhance that the concentration of CNTs caused the structure of as-coated Ni-P conversion from amorphous to crystalline. Compared to the Ni-P coating, the resistance of corrosion of composite coating (Ni-P-CNT) are better, and they become much better with the increase of the CNT concentration. The addition of CNT makes the coating denser, and the presence of CNT decreases the size of grain to the heat treated formulas but too much CNT deposited on the substrate leads to a high region of the CNT wrapped together and the resulting agglomeration that occur is very unfavorable to coating, resulting in the lead resistance of the corrosion of the composite coating which becomes worse. © TJPRC Pvt. Ltd.