There are several advantages to the MIG(Metal Inert Gas)process,which explains its increased use in variouswelding sectors,such as automotive,marine,and construction.A variant of the MIG process,where the sameequipmen...There are several advantages to the MIG(Metal Inert Gas)process,which explains its increased use in variouswelding sectors,such as automotive,marine,and construction.A variant of the MIG process,where the sameequipment is employed except for the deposition of a thin layer of flux before the welding operation,is the AMIG(Activated Metal Inert Gas)technique.This study focuses on investigating the impact of physical properties ofindividual metallic oxide fluxes for 304L stainless steel welding joint morphology and to what extent it can helpdetermine a relationship among weld depth penetration,the aspect ratio,and the input physical properties ofthe oxides.Five types of oxides,TiO_(2),SiO_(2),Fe_(2)O_(3),Cr_(2)O_(3),and Mn_(2)O_(3),are tested on butt joint design withoutpreparation of the edges.A robust algorithm based on the particle swarm optimization(PSO)technique is appliedto optimally tune the models’parameters,such as the quadratic error between the actual outputs(depth and aspectratio),and the error estimated by the models’outputs is minimized.The results showed that the proposed PSOmodel is first and foremost robust against uncertainties in measurement devices and modeling errors,and second,that it is capable of accurately representing and quantifying the weld depth penetration and the weld aspect ratioto the oxides’thermal properties.展开更多
In recent times,scientists and engineers have been most attracted to electrically conducted nanofluids due to their numerous applications in various fields of science and engineering.For example,they are used in cance...In recent times,scientists and engineers have been most attracted to electrically conducted nanofluids due to their numerous applications in various fields of science and engineering.For example,they are used in cancer treatment(hyperthermia),magnetic resonance imaging(MRI),drugdelivery,and magnetic refrigeration(MR).Bearing in mind the significance and importance of electrically conducted nanofluids,this article aims to study an electrically conducted water-based nanofluid containing carbon nanotubes(CNTs).CNTs are of two types,single-wall carbon nanotubes(SWCNTs)and multiple-wall carbon nanotubes(MWCNTs).The CNTs(SWCNTs and MWCNTs)have been dispersed in regular water as base fluid to form waterCNTs nanofluid.The Brinkman Type nanofluid model is developed in terms of time-fractional domain.The ramped heating and sinusoidal oscillations conditions have been taken at the boundary.The model has been solved for exact analytical solutions via the fractional Laplace transform method.The exact solutions have been graphically studied to explore the physics of various pertinent flow parameters on velocity and temperature fields.The empirical results reveal that the temperature and velocity fields decreased with increasing values of fractional parameters due to variation in thermal and momentum boundary layers.It is also indicated that the isothermal velocity and temperature are higher than ramped velocity and temperature.展开更多
The primary objective of global studies is to develop the properties and durability of polymers for various applications.When it comes to dental disability,denture base materials must have sufficient mechanical and tr...The primary objective of global studies is to develop the properties and durability of polymers for various applications.When it comes to dental disability,denture base materials must have sufficient mechanical and tribological performance in order to withstand the forces experienced in the mouth.This work aims to investigate the effects of the addition of low content of cellulose nanocrystals(CNC)on the mechanical and tribological performance of the polymethyl methacrylate(PMMA)nanocomposites.Different weight percent of CNC(0,0.2,0.4,0.6,and 0.8 wt%)were added to the PMMA matrix followed by ball milling to evenly distribute the nanoparticles reinforced phase in the matrix phase.The findings emphasize the significant impact of CNC integration on the performance of PMMA nanocomposites.By increasing the content of the CNC nanoparticles,the mechanical properties of PMMA were improved.In addition,the tribological outcomes demonstrated a significant reduction in the friction coefficient besides an enhancement in the wear resistance as the weight percentage of nanoparticles increased.The surface of the worn samples was investigated by utilizing SEM to identify the wear mechanisms corresponding to the different compositions.In addition,a finite elment model(FEM)was developed to ascertain the thickness of the worn layer and the generated stressed on the surfaces of the nanocomposite throughout the friction process.展开更多
文摘There are several advantages to the MIG(Metal Inert Gas)process,which explains its increased use in variouswelding sectors,such as automotive,marine,and construction.A variant of the MIG process,where the sameequipment is employed except for the deposition of a thin layer of flux before the welding operation,is the AMIG(Activated Metal Inert Gas)technique.This study focuses on investigating the impact of physical properties ofindividual metallic oxide fluxes for 304L stainless steel welding joint morphology and to what extent it can helpdetermine a relationship among weld depth penetration,the aspect ratio,and the input physical properties ofthe oxides.Five types of oxides,TiO_(2),SiO_(2),Fe_(2)O_(3),Cr_(2)O_(3),and Mn_(2)O_(3),are tested on butt joint design withoutpreparation of the edges.A robust algorithm based on the particle swarm optimization(PSO)technique is appliedto optimally tune the models’parameters,such as the quadratic error between the actual outputs(depth and aspectratio),and the error estimated by the models’outputs is minimized.The results showed that the proposed PSOmodel is first and foremost robust against uncertainties in measurement devices and modeling errors,and second,that it is capable of accurately representing and quantifying the weld depth penetration and the weld aspect ratioto the oxides’thermal properties.
基金fund from King Saud University through Deanship of Scientific Research,Research Group Program.The authors would also like to acknowledge Ministry of Education(MOE)and Research Management Centre-UTM,Universiti Teknologi Malaysia(UTM)for the financial support through vote Nos.5F004,07G70,07G72,07G76,07G77and 08G33 for this research.
文摘In recent times,scientists and engineers have been most attracted to electrically conducted nanofluids due to their numerous applications in various fields of science and engineering.For example,they are used in cancer treatment(hyperthermia),magnetic resonance imaging(MRI),drugdelivery,and magnetic refrigeration(MR).Bearing in mind the significance and importance of electrically conducted nanofluids,this article aims to study an electrically conducted water-based nanofluid containing carbon nanotubes(CNTs).CNTs are of two types,single-wall carbon nanotubes(SWCNTs)and multiple-wall carbon nanotubes(MWCNTs).The CNTs(SWCNTs and MWCNTs)have been dispersed in regular water as base fluid to form waterCNTs nanofluid.The Brinkman Type nanofluid model is developed in terms of time-fractional domain.The ramped heating and sinusoidal oscillations conditions have been taken at the boundary.The model has been solved for exact analytical solutions via the fractional Laplace transform method.The exact solutions have been graphically studied to explore the physics of various pertinent flow parameters on velocity and temperature fields.The empirical results reveal that the temperature and velocity fields decreased with increasing values of fractional parameters due to variation in thermal and momentum boundary layers.It is also indicated that the isothermal velocity and temperature are higher than ramped velocity and temperature.
基金the King Salman Center for Disability Research for funding this work through Research Group(No.KSRG-2023-538).
文摘The primary objective of global studies is to develop the properties and durability of polymers for various applications.When it comes to dental disability,denture base materials must have sufficient mechanical and tribological performance in order to withstand the forces experienced in the mouth.This work aims to investigate the effects of the addition of low content of cellulose nanocrystals(CNC)on the mechanical and tribological performance of the polymethyl methacrylate(PMMA)nanocomposites.Different weight percent of CNC(0,0.2,0.4,0.6,and 0.8 wt%)were added to the PMMA matrix followed by ball milling to evenly distribute the nanoparticles reinforced phase in the matrix phase.The findings emphasize the significant impact of CNC integration on the performance of PMMA nanocomposites.By increasing the content of the CNC nanoparticles,the mechanical properties of PMMA were improved.In addition,the tribological outcomes demonstrated a significant reduction in the friction coefficient besides an enhancement in the wear resistance as the weight percentage of nanoparticles increased.The surface of the worn samples was investigated by utilizing SEM to identify the wear mechanisms corresponding to the different compositions.In addition,a finite elment model(FEM)was developed to ascertain the thickness of the worn layer and the generated stressed on the surfaces of the nanocomposite throughout the friction process.