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In the present work, predictive modelling and optimization with the adaptive network based fuzzy inference system (ANFIS) modelling of the mechanical properties of laser-coated NB/SiC/Ni welds was studied based on the Taguchi design by laser cladding. An ANFIS model based on a Sugeno type fuzzy inference system was developed for predicting the hardness properties of SiC/BN/Ni welds by laser cladding with experimental data required for network training and prediction. Based on analysis of variance, three important factors were taken as inputs for the fuzzy logic inferences, while the hardness properties were taken as the output of the ANFIS. The microstructure of welds was analysed using scanning electron microscopy with an energy-dispersive X-Ray spectrometer. Highly developed leaf-like dendrites and eutectic crystals were found in some areas of the melting zone for the BN/SiC/Ni weld, which was significantly hardened. The ANFIS model based on Taguchi's design provides a better pattern of response because the predicted and experimental values were highly similar. As a result, a satisfactory result was achieved between the predicted and experimental values of hardness in laser-coated NB/SiC/Ni welds, whereby the success and validity of the method was verified. [ABSTRACT FROM AUTHOR]

Understanding trends in the formation of the intermetallic compound (IMC) layer in Al/Fe bimetallic composites can aid in significantly improving their mechanical properties. However, it is currently challenging to predict IMC layer formation during hot-dip aluminizing. Furthermore, the results from previous studies are difficult to compare owing to the variation in the process parameters used. Therefore, to understand how temperatures and holding times affect the thickness and hardness properties of IMC layers, we investigated the interfacial properties of aluminized stainless steel in molten Al-Si-Mg. AISI 420 stainless steel was hot-dip aluminized in an Al–Si–Mg alloy melt for 10–120 min at four different temperatures: 700, 750, 800, and 850 °C. Morphology, type, and element distribution of the phases formed in the reaction layer and the reduction rate of the aluminizing process were studied. Notably, while the reaction layer thickness increased with increasing aluminizing temperature when the holding time was low, long-term reaction caused the reaction layer to become thicker at lower temperatures. The mechanism of this morphological transformation is discussed. The results demonstrated effective trends in controlling the morphology of the intermetallic compound layer with respect to various hot-dip Al plating process parameters. [ABSTRACT FROM AUTHOR]

In this study, the changes in microstructure, hardness, corrosion and wear properties of Al-Mg with 3% Mg content and new type Al-Mg-Bi alloys with 1.3% Bi addition were investigated with the application of thermomechanical process on the aging heat treatment characteristics. As a result of the applied thermomechanical process, a finer grained structure was obtained and a higher hardness value was achieved compared to the casting alloys. Bright phases in SEM micrographs were detected as (rod-shaped) intermetallic (Al6Mn) particles in TEM analyses. Additionally, it was determined that the independent dark particles in the Al matrix were Mg2Si phases. Both alloys showed evidence of the Al3Mg2 phase. However, corrosion tests have shown that the Al-Mg-Bi1.3 alloys with the addition of bismuth have higher corrosion resistance than the Al-Mg alloys. The Al-Mg-Bi1.3 alloys also exhibited improved wear resistance in dry and corrosive wear tests. While the wear of the investigated alloys in a dry environment is associated with an improvement in hardness, wear resistance in corrosive media is improved by the addition of Bi, which reduces the formation of certain phases. [ABSTRACT FROM AUTHOR]

The present study investigates the mechanical properties of AlP0507-based metal matrix composites reinforced with multi-walled carbon nanotubes (MWCNTs) and rice husk (RHA) using experiments and numerical simulation. To achieve this goal, an AlP0507-based MWCNT/RHA hybrid metal matrix composite was fabricated by stir casting method. Subsequently, microstructural analysis using field emission scanning electron microscopy (FESEM) and EDAX was carried out for different weight ratios of MWCNTs/RHA. In addition, the tensile, impact, and hardness characteristics of MWCNT/RHA-reinforced aluminum metal matrix composite (AMMC) and hybrid MWCNT/RHA-reinforced aluminum metal matrix composite (HAMMC) were experimentally investigated for different reinforcement weight concentrations. In addition, the tensile, von Mises stress distribution, strain, and deformation behavior of AMMC and HAMMC were numerically investigated using the commercial software Digimat-FE supporting the RVE approach considering particle inclusions. It was also noticed that the optimal addition of RHA/MWCNTs to the AlP0507 melt led to an improvement in the tensile strength, hardness, and impact properties of the composites when compared to the AlP0507 material without any reinforcement. It can also be noticed that after a certain optimal percentage of RHA reinforcement, the tensile strength of AMMC and HAMMC decreases. Further, the examination of the numerical stress distribution facilitates the prediction of the regions that exhibit high levels of stress concentration, potential locations of fracture, or areas where the material may undergo excessive deformation. [ABSTRACT FROM AUTHOR]

In the present work, predictive modelling and optimization with the adaptive network based fuzzy inference system (ANFIS) modelling of the mechanical properties of laser-coated NB/SiC/Ni welds was studied based on the Taguchi design by laser cladding. An ANFIS model based on a Sugeno type fuzzy inference system was developed for predicting the hardness properties of SiC/BN/Ni welds by laser cladding with experimental data required for network training and prediction. Based on analysis of variance, three important factors were taken as inputs for the fuzzy logic inferences, while the hardness properties were taken as the output of the ANFIS. The microstructure of welds was analysed using scanning electron microscopy with an energy-dispersive X-Ray spectrometer. Highly developed leaf-like dendrites and eutectic crystals were found in some areas of the melting zone for the BN/SiC/Ni weld, which was significantly hardened. The ANFIS model based on Taguchi’s design provides a better pattern of response because the predicted and experimental values were highly similar. As a result, a satisfactory result was achieved between the predicted and experimental values of hardness in laser-coated NB/SiC/Ni welds, whereby the success and validity of the method was verified.

Understanding trends in the formation of the intermetallic compound (IMC) layer in Al/Fe bimetallic composites can aid in significantly improving their mechanical properties. However, it is currently challenging to predict IMC layer formation during hot-dip aluminizing. Furthermore, the results from previous studies are difficult to compare owing to the variation in the process parameters used. Therefore, to understand how temperatures and holding times affect the thickness and hardness properties of IMC layers, we investigated the interfacial properties of aluminized stainless steel in molten Al-Si-Mg. AISI 420 stainless steel was hot-dip aluminized in an Al–Si–Mg alloy melt for 10–120 min at four different temperatures: 700, 750, 800, and 850 °C. Morphology, type, and element distribution of the phases formed in the reaction layer and the reduction rate of the aluminizing process were studied. Notably, while the reaction layer thickness increased with increasing aluminizing temperature when the holding time was low, long-term reaction caused the reaction layer to become thicker at lower temperatures. The mechanism of this morphological transformation is discussed. The results demonstrated effective trends in controlling the morphology of the intermetallic compound layer with respect to various hot-dip Al plating process parameters.

This research evaluates the influence of process parameters of the spark plasma sintering (SPS) technique on the densification and hardness properties of ECR/TiO2/PI nanocomposite. Taguchi's design of experiment was employed for designing the sintering process, while analysis of variance (ANOVA) was adopted to evaluate the contribution of the factor variables to the response variable of hardness and density. 10 wt% ECR-glass and 4 wt% TiO2 were used as reinforcements in the polyimide matrix at varying pressure and temperature for the physical experiment. The sintered samples were examined using a scanning electron microscope, nanoindentation tests, and an Archimedes-based density tester. The optimization was performed on total 9 numbers of runs of experiments. The most desirable SPS processing parameters were recorded at 320 °C and a pressure of 30 MPa. Under this processing condition, a density of 1.49 g/cm3 (relative density of 98.7%), Vickers hardness, and nanoindentation hardness value of 33.46 HV and 361.30 MPa, respectively, were obtained. This research work suggests a facile way to produce high-performance PI nanocomposite for various engineering applications, such as mechanical load-bearing and insulation applications. [ABSTRACT FROM AUTHOR]

Titanium alloy (Ti-6Al-4V) has been mostly used for medical implants due to its good chemical and mechanical properties. However, this alloy has tendency to emanate toxic V and Al due to its low corrosion resistance in body conditions. In this work, an experimental study of laser cladding Ti-Al2O3 coatings with different Al2O3 fractions (5 wt.% Al2O3, 8 wt.% Al2O3, and 10 wt.% Al2O3) was carried out to establish a coating which could improve the hardness and corrosion resistance of Ti-6Al-4V alloy. Laser parameters of 900 W power, 0.6 m/min laser scan speed, and 2 l/min powder feed were used in this research. The microstructure, phase constituents, microhardness, and corrosion of the resultant coatings were characterized by scanning electron microscope (SEM), optical microscope (OPM), X-Ray Diffractometer (XRD), Vicker hardness tester, and potentiostat respectively. Results showed that a defect free coating was achieved at a coating with less Al2O3 content. Increase in Al2O3 addition resulted in increment of hardness with Ti-10 wt.% Al2O3 coating achieving an optimum hardness of about 2.2 times greater than that of the substrate. Moreover, considerable increment in corrosion resistance of Ti-6Al-4V alloy was achieved after laser deposition of various Ti-Al2O3 admixed coatings. An optimal corrosion rate reduction of about 81% and polarization resistance increment of 709% over the substrate were achieved at Ti-5 wt.% Al2O3 due to low porosity within the coating layer. It has been established that fabricating Ti-Al2O3 on Ti6Al4V through laser could be used in improving the surface hardness values and corrosion resistance. [ABSTRACT FROM AUTHOR]

Depending on the conditions of their use, most equipment gets deteriorated in time. In this paper the corrosion rate (CR) was verified by using the experiment of weight loss (WL) of specimens from steam boiler pipes (SBP) made of 1010 carbon steel with a thickness of 4 mm. CR was calculated by specimens’ weight loss in the corrosive environment at 25 °C in 5% NaCl - 10% H2O2 solution which reproduces the environment in the plant during specific times. The mechanical properties which were verified include hardness test and tensile test. The results that have been obtained through tensile curves and hardness properties on specimens 1 and 2 were compared to a non-service specimen (3) made of 1010 carbon steel. It is concluded that there was an increase in the properties of tensile and a decrease of hardness for both specimens by comparing them with a non-service specimen. Due to overheating, a deposition of layers of lime (CaO) on the pipes was caused. It is noticed that the decrease of the mechanical properties leads to increased corrosion.

Depending on the conditions of their use, most equipment gets deteriorated in time. In this paper the corrosion rate (CR) was verified by using the experiment of weight loss (WL) of specimens from steam boiler pipes (SBP) made of 1010 carbon steel with a thickness of 4 mm. CR was calculated by specimens' weight loss in the corrosive environment at 25 °C in 5% NaCl - 10% H2O2 solution which reproduces the environment in the plant during specific times. The mechanical properties which were verified include hardness test and tensile test. The results that have been obtained through tensile curves and hardness properties on specimens 1 and 2 were compared to a non-service specimen (3) made of 1010 carbon steel. It is concluded that there was an increase in the properties of tensile and a decrease of hardness for both specimens by comparing them with a non-service specimen. Due to overheating, a deposition of layers of lime (CaO) on the pipes was caused. It is noticed that the decrease of the mechanical properties leads to increased corrosion. [ABSTRACT FROM AUTHOR]

Determination of hardness and stiffness for materials is extremely important because of its rule in the design of engineering applications. This work investigated the possibility of increasing A308 steel hardness through the burning of olive Pomace. Carbonizing, nitrating and cyaniding methods were employed. Results have shown that hardness of stainless steel samples is directly proportional with the temperature and the amount of carbon in the test specimen. [ABSTRACT FROM AUTHOR]

Steel has played a primary role as structural and fabricating materials in various industrial applications—including the construction sector. One of the most important properties of steel that required a constant improvement is corrosion resistance specifically in corrosive environment. For this purpose, various approaches have been conducted through different heat treatment parameters to compare its microstructural engineering on chemical and mechanical properties. In this paper, correlation of different microstructure on corrosion resistance and hardness properties have been investigated. Three different heat treatment cycle have been applied on carbon steel with same composition to prepare dual-structure (DS) steel that consisted of ferrite/pearlite and triple-structure (TS) with ferrite/pearlite/bainite and ferrite/bainite/martensite. Phase transformation during heat treatment process was analyzed through in-situ ultra-high temperature confocal microscopy. Effect of corrosion behavior on these steels was investigated by Tafel plot, Scanning Electron Microscopy (SEM), 3D laser scanning confocal microscopy (3DLSCM), and calculation of phase volume fraction by ImageJ. Mechanical test was conducted by Vickers hardness test. It has been found that TS steels that have improvement in corrosion resistance accounted around 5.31% and hardness value for up to 27.34% more than DS steel, because of tertiary phase—bainite/martensite. This corrosion rate was reduced due to decreased numbers of pit growth and lower level of boundary corrosion as bainite/martensite phases emerged.

Steel has played a primary role as structural and fabricating materials in various industrial applications—including the construction sector. One of the most important properties of steel that required a constant improvement is corrosion resistance specifically in corrosive environment. For this purpose, various approaches have been conducted through different heat treatment parameters to compare its microstructural engineering on chemical and mechanical properties. In this paper, correlation of different microstructure on corrosion resistance and hardness properties have been investigated. Three different heat treatment cycle have been applied on carbon steel with same composition to prepare dual-structure (DS) steel that consisted of ferrite/pearlite and triple-structure (TS) with ferrite/pearlite/bainite and ferrite/bainite/martensite. Phase transformation during heat treatment process was analyzed through in-situ ultra-high temperature confocal microscopy. Effect of corrosion behavior on these steels was investigated by Tafel plot, Scanning Electron Microscopy (SEM), 3D laser scanning confocal microscopy (3DLSCM), and calculation of phase volume fraction by ImageJ. Mechanical test was conducted by Vickers hardness test. It has been found that TS steels that have improvement in corrosion resistance accounted around 5.31% and hardness value for up to 27.34% more than DS steel, because of tertiary phase—bainite/martensite. This corrosion rate was reduced due to decreased numbers of pit growth and lower level of boundary corrosion as bainite/martensite phases emerged. [ABSTRACT FROM AUTHOR]