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Friction stir consolidation (FSC) is a promising manufacturing process for metal matrix hybrid composites (MMHC) with excellent mechanical properties. The originality of this study involves the exploration of the fabrication technique (FSC), the selection of materials and the optimization of wear behavior via a systematic investigation of the process parameters. The aim of this study was to optimize and investigate the wear behavior of MMHCs fabricated using FSC. The optimum sample was nominated for thermogravimetric analysis (TGA) and wear morphology analysis using SEM imaging. Material compositions of 7.5%wt of SiC, 7.5%wt of ZrO2 and 85%wt of AZ61 were considered for the experimental investigation. The RSM Box–Behnken design followed by a genetic algorithm (GA) was implemented to optimize the process parameters of sliding distance, speed and load at 350 m, 500 m and 650 m; 220 rpm, 240 rpm and 260 rpm; and 20 N, 30 N and 40 N, respectively. The RSM Box–Behnken result showed that the minimum wear rate of 0.008 mg/m was obtained at 350 m, 20 N and 240 rpm, whereas GA predicted the optimum parametric setup at 350 m, 20 N and 220 rpm. Additionally, TGA showed the material's thermal stability from 375 °C to 480 °C. Generally, MMHCs exhibited a promising wear performance, proving the effectiveness of the FSC. [ABSTRACT FROM AUTHOR]

Ethiopia has a large coverage of bamboo plants that are used for furniture making and house building. So far, researchers have not studied the strength of Ethiopian bamboo fibers, which are utilized for composite applications. The current study measured the strength of bamboo fibers based on various testing lengths and calculated the predictive tensile strength using a modified Weibull distribution. Moreover, the quality of the extraction machine is evaluated based on shape and sensitivity parameters. This research paper incorporates the coefficient of variation of the fiber diameters, considering the defects distribution through the length for measuring the predictive strength of the fibers. The fiber diameters were calculated using the area weight methods, which had its density measured using a Pycnometer. It has been examined that as the testing gauge length and coefficient variation of fiber diameter simultaneously increased, the tensile strength of the bamboo fibers decreased. The shape parameter, sensitivity parameter, and characteristic strength of Injibara bamboo (Y. alpina) are 6.02–7.83, 0.63, and 459–642 MPa, whereas Kombolcha bamboo (B. oldhamii) are 5.87–10.21, 0.33, and 408–638 MPa, as well as Mekaneselam bamboo (Y. alpina) are 5.86–9.63, 0.33 and 488–597 MPa, respectively. [ABSTRACT FROM AUTHOR]

There is high demand of Aluminium material for various engineering applications but the main problem being low wear and corrosion resistance. Laser beam application for surface modification of engineering materials gets high attention in research and industries due to superior surface performance for wear and corrosion resistance. In the present research article, an attempt has been made to improve the properties of Aluminium by laser surface alloying technology. Laser surface alloying of commercially pure aluminium with titanium and zinc metal powders at 50% combination has been conducted using CO2 laser power from 1600 to 2000 W. The experiments have been planned through design of experiment using Response Surface Methodology (RSM). The mathematical modelling and optimisation of process parameters such as specific laser power scan speed and heat input for optimum value of Micro hardness has been carried out using RSM with three factors and five levels. The statistical significance of the data has been carried out using Analysis of Variance (ANOVA).The alloy made by Al-TiZn shows improved hardness by 47% due to good laser surface alloying which has created dendrite microstructure without any metallurgical defects. The optimised value of laser energy density was found to be 37 J/mm2. It has been investigated that the optimum values of laser speed and heat input are 84 m/s and 61.50 watt respectively for micro hardness value of 56HV. Hardness decreases from top alloy zone towards substrate material since high energy creates more depth where the concentration of alloying elements is less. The friction coefficient of Al-TiZn alloy was found to be less by 23% than unalloyed aluminium substrate. The depth of laser alloyed has been increased with laser power and heat input from laser beam. Higher electron microscopy analysis shows that a sound alloying has been created without surface and subsurface defects. The present investigation is expected to help automobile and aerospace industries where the wear and corrosion resistance of the material are of major concern. [ABSTRACT FROM AUTHOR]

Metal-polymer-metal (MPM) sandwich composites are in the class of proficient engineering materials which give outstanding strength-to-weight ratios because of their comparatively low density. These materials are vital constituents within the automobile, aerospace, marine, and civil construction industries as substitutes for sheet metals that considerably reduce weight while not compromising functionality. Moreover, these materials have supplementary qualities like sound dampening and thermal insulation capabilities. For these materials to be utilized within the aforesaid industries, they need to bear numerous forming processes that are essential in product manufacturing. This paper investigated formability analysis of metal-polymer sandwich composites made of "AW 6082-PVC-AW 6082 (APA)" and "galvanized steel-PVC-galvanized steel (GPG)" sandwich sheets, considering epoxy structural adhesives as the binding agent, via FEA simulation. All the FEA simulations were performed using Altair HyperWorks software. For evaluating the formability, the actual limit dome height (LDH)—biaxial strain path—tests were simulated using FEM software. The results analyzed are forming limit diagram (FLD), punch force distribution, and a dome height at diverse conditions of punch velocity and friction. A comparison is made to represent the best combinations for formability of the sandwich composites. Maximum formability and dome height are attained at low friction conditions and forming speed. It has also been observed that LDH simulations are very sensitive to friction, and it has a substantial impact on the test outputs. Maximum thinning (or fracture) generally moves away from the apex of the dome towards the die corner radius as the friction increases from zero upwards. [ABSTRACT FROM AUTHOR]

In this study, NACA0018 airfoil surface conformity test was conducted using API tracker3 in combination with SpatialAnalyzer (SA) and modeling software SolidWorks. Plaster of Paris is used as a plug making material and a woven-type fiberglass is used as mold and airfoil surface making material. For airfoil surface analysis, three-dimensional model of the airfoil surface was developed in SolidWorks software and imported in IGES file format to SpatialAnalyzer (SA) software. Then, measurements were taken from manufactured airfoil surface using laser tracker through surface scanning method. Surface conformity test was conducted through fitting of measured points to surface model imported from SolidWorks to SpatialAnalyzer (SA) software. The optimized fit summary result shows that the average fit difference is 0.0 having standard deviation from 0.22224 from the average and zero with RMS of 0.2210. The maximum magnitude of the difference including x and y together is 0.5336 and the minimum −0.5077. Thus, with a given range of surface quality specification, laser tracker is an easy and reliable measurement and inspection tool to be considered. [ABSTRACT FROM AUTHOR]