This research focused on the die exit width, ram speed and temperature effects on extruded Al 6063 alloy mechanical properties. It is a multiple approach that involves numerical, experimental and simulation methods in optimizing the extrusion process. The Q-Form was used in extruded sample flow stress and strain distribution analysis. The result revealed die exit width as the parameter with the most significant influence on Al 6063 alloy tensile strength and hardness, followed by extrusion temperature and then ram speed. The die width increase from 6mm to 8mm yields 73.5 % and 75.8 % tensile strength and hardness increase. The optimized process parameters predicted by the model are a speed of 16.2567 mm/s, a temperature of 526.334 °C, and a die exit diameter of 7.1862 mm, which yields a tensile strength of 151.031 MPa and a hardness of 183.644 HB, respectively. Based on Qform findings, the sample extruded using these optimal parameters yielded uniform metal flow products with low stress concentration. The research enables deep knowledge into the extrusion parameters and mechanical properties relationship, leading to aluminum alloy hot extrusion process optimization. This research has contributed to the more effective and efficient extrusion process development that can be applied in many aluminum extrusion industries. The product quality can be improved through optimized process parameters, thereby reducing the cost of production and boosting the extrusion process's overall efficiency.

The aim of this study was to investigate the modifications of the mechanical properties of polypropylene (PP) by incorporating elastomers, while considering the impact on its stiffness. Specifically, the research focused on determining the optimal loading of elastomer to achieve desirable properties and exploring the influence of these processes on the morphology and mechanical behavior of the prepared blends. Thermoplastic elastomers (TPEs) consisting of polypropylene and natural rubber (PP/NR) were prepared using a melt-mixing process, and the mechanical properties of the blends were evaluated. The stress-strain properties of the blends revealed a successful modification of PP, transforming it from a stiff and strong thermoplastic into a stiff and tough thermoplastic elastomer when 10% NR was included in the PP matrix. As the loading of NR increased, a reduction in tensile strength (TS) and modulus (E) of the blends was observed, while elongation at break (EB) increased. The flexural strength of unmodified PP was 45.9 MPa, which decreased with increasing NR loading. Similarly, the impact strength of unmodified PP was 25.8 KJ/m², whereas the values for 10%, 20%, 30%, and 40% NR inclusion were 30.8, 24.3, 20.6, and 15.2 KJ/m², respectively. The melt flow index (MFI) of unmodified PP was 14.1 g/10 min, while the values for 10%, 20%, 30%, and 40% NR inclusion were 19.4, 15.7, 11.6, and 10.2 g/10 min, respectively. The best combination of mechanical properties was observed at 10% NR inclusion in the PP matrix. The micrograph of the blends, as observed from SEM micrographs, supported the modification of PP, resulting in the production of TPE with observable adhesion sites, indicating good compatibility between the components. In a nutshell, a significant 47% increase in impact strength was achieved through the modification process.

Hot rolled 40Cr and W6Mo5Cr4V2 steels were diffusion-welded by using a 4-staged process including uniaxial 50 kN compression at 1200 oC in 10^-5 mbar vacuum with following cooling down to room temperature. Structural 40Cr and high-speed tool W6Mo5Cr4V2 steels are dissimilar, since they are different (i) in content of host Fe element and alloying Cr, W, V, Mo elements, (ii) in phase composition (40Cr steel is single-phased and W6Mo5Cr4V2 steel is multi-phased), (iii) in microstructure (homogeneous inclusions-less microstructure is characteristic for 40Cr steel, composite microstructure consisting of matrix Fe-based phase with metal (W, V, Mo) carbides is characteristic of W6Mo5Cr4V2 steel), and (iv) in grain structure (40Cr steel is coarse-grained with grain ~100 µm size and W6Mo5Cr4V2 steel is fine-grained with grain size of several µm). Phase composition, microstructure and grain structure of the steels are retained after welding. Diffusion redistribution of Fe, Cr, W, V, Mo atoms results in forming the diffusion zones with different widths (several µm for W, V and Mo, ~25 for Cr and ~15 µm for Fe). Resulting concentration Cr profiles are typical for diffusion from limited sources and could be satisfactorily described by diffusion coefficient equal to ~1.1∙10^-14 m²∙s^-1 (the coefficient is weighted over the entire temperature range from 1200 oC to room temperature). Within the diffusion Cr and Fe zones, the Vickers microhardness decreases from ~2000 HV (for W6Mo5Cr4V2 steel) to ~530 HV (for 40Cr steel). During room-temperature tensile tests, the diffusion-welded steels were always fractured not in the diffusion joint but in 40Cr steel.

Leaf springs are machine elements that provide safety and driving comfort by storing the energy caused by the loads coming to the chassis and transport elements depending on the road conditions. Leaf springs are suspension elements commonly used particularly in heavy commercial vehicles. In this study, prototype leaf spring production was realized by forming the metal sheet and making heat treatments. Residual stress analysis, hardness, bending and strain gauge measurements were performed to examine the mechanical properties of the leaf spring produced. After the applied tempering process, the leaf spring microstructure was examined.

This study examined the nexus between electronic human resource management (e-HRM), employee engagement and organizational performance in small- and medium-sized Saudi firms. In total, 180 participants were randomly selected using convenience sampling. Structural equation model-partial least squares SEM-PLS, was applied for analysis purposes. The outcomes of this study show that there is no statistically significant relationship between organizational performance and e-HRM. E-HRM and employee engagement, as well as employee engagement and organizational performance, have a strong beneficial association. The results highlight the necessity of establishing efficient E-HRM procedures as a strategy to raise employee engagement and promote organizational performance.

Stainless steel (SS) and Titanium alloy (Ti) are the most commonly used materials in many industrial fields such as the automotive and aerospace industry. Stainless steel has good corrosion resistance and titanium alloy has an extremely lightweight characteristic. The combination of both materials has become a tremendous innovation in the industrial sector. Resistance spot welding which has commonly applied in many industrial fields is a good consideration to join these two dissimilar materials due to the high efficiency that could be achieved by using this method. However, the way of joining these dissimilar materials should be carefully considered due to the significant difference in mechanical properties between SS and Ti. In the present study, 3 mm of SS316L and Ti6Al4V sheets were joint under the resistance spot welding method with an aluminum interlayer. The optimized welding parameters were provided under the Taguchi method L9 orthogonal array along with the mechanical properties’ investigation. The optimum welding parameters were 11 kA of weld current, 30 Cycles of welding time, and 5 kN of electrode force which produced 8.83 kN tensile-shear load of the joint. The mechanical structure analysis shows the different morphology between stainless steel and titanium interfaces and the intermetallic compound layer was formed on the SS/Al and Al/Ti interfaces. The EDX analysis shows the atomic diffusion-reaction on the application of aluminum as an interlayer on the SS/Ti joint.

In this research, acheiving submicrocrystalline structure in commercially pure Al is investigated using severe plastic deformation (SPD) method named constrained groove pressing (CGP). In order to find a procedure that acts more effective in grain refinement and mechanical properties enhancement, three experimental procedures were defined and carried out. The procedures were defined by variables of die groove angle (45° and 50°) and using Cu covering sheets at top and down of the specimens instead of rigid die surface as a lubricant. Grain refinement during CGP process was investigated by William-hall analysis on X-Ray diffraction pattern and scanning electron microscopy (SEM). The results show that CGP process in all three procedures can severely refine the microstructure to an ultra-fine grained (UFG) structure with less than 1 micron grain size. Although grain refinement rate in die with 50° groove angle is higher but because of facility of applying extra CGP passes in 45° groove angle die with covering sheets (procedure 2), final grain size in procedure B is lesser. Mechanical properties of CGPed samples was investigated by tensile and hardness tests and the results show that at primary passes in all procedures strength-related properties increases significantly through a decrease in elongation, but at subsequent passes this behaviuor is diffentent for each procedure.

Growth of the volumes of dangerous and critical welded metal structures constructed under low temperatures imposes additional requirements on the mechanical properties of the weld joints, particularly, on the impact resistance of the weld joint and on the stability of its values. It can be achieved by using coated electrodes with ultradisperse powders of alloying elements in the coating. To develop new improved welding materials we need to optimize the systems of weld metal alloying to meet the increasingly stringent requirements to the welding-operational characteristics. Introduction of a complex ultradisperse powder (Al₂O₃, SiO₂, TiO₂, Ni) into the electrode coating applied for manual metal-arc welding ensures more stable process of electrode metal fusing and its transfer into the welding bath, improves the performance characteristics of the welded metal.

In this paper, the severe plastic deformation method (SPD) known as constrained groove pressing (CGP) was applied to produce ultrafine-grained microstructure in IF steel sheets. In the CGP technique, samples are subjected to repetitive shear deformation under the plane strain deformation condition using the constrained grooved and flat dies. For assessment of microstructure and mechanical properties of the CGPed IF steel sheet, several testing such as: uniaxial tensile test, hardness measurements, scanning electron microscopy (SEM) and X-ray diffraction analysis have been utilized. Finally, it was observed that the grains are significantly refined after the 16-step pressing of the interstitial free (IF) steel sheets. The grains were reduced from 45µm to 243 nm after four passes.

In this work, novel cellulosic fibers are extracted from Washingtonia Filifera (WF) plant using an environment friendly technique. Morphological, physico-chemical, thermal and mechanical properties are reported in this paper. Micro graphical SEM shows the presence of cells in the fiber. FTIR and XRD experimental analyzes show a cristinality index of 48.88%, and the WF fibers are found to be thermally stable until 201°C by using TGA and DTG thermo graphic analyzes with an appropriate activation energy of 72.46 kJ/mol, where Young modulus and tensile strength of strain were determined using tensile tests of single fiber at 2.17 GPa, 134 MPa and 26.55%, respectively. Mechanical properties are analyzed using a statistical method.