Without a doubt, lightweight materials of high strength are in high demand in the automotive, aerospace, biomedical, and other industries that require such materials. Processing or manufacturing such materials has been a vital topic in contemporary research, as well as material development in the industry. A possible solution for the processing of lightweight materials of high strength is to target lightweight materials by nature such as magnesium and improve their mechanical properties such as stiffness, strength, and hardness. The aforementioned properties are sometimes achieved by processing soft and light materials through High-Pressure Torsion. In this work, Magnesium with Silicon Carbide nanoparticles (Mg-SiC) was strengthened and hardened through the High-Pressure Torsion (HPT) processing technique. The samples were compressed with a pressure of 6.0 GPa and twisted at the rotating speed of 1 rpm with varying numbers of turns N = 0, N = 1, N = 5 and N = 10 at a temperature of 23°C. The processed samples were prepared for the experimental investigation of microstructural characterization and hardness test examinations. Microstructural results showed that grain refinements of material can be achieved through HPT processing methods, which reduced the average grain sizes of unprocessed (N = 0) Mg alloy samples from 149.9 µm to 27.1 µm after processing ten turns. However, hardness test results do not indicate any significant improvement after one HPT processing turn although homogeneity is attained at five processing turns within the nanocomposites.

For the past 19 years, high entropy alloys (denoted as HEAs) have piqued the interest of many researchers due to their unique properties. Sputtering High Entropy Alloys on bulk materials, on the other hand, have been widely utilized due to their low cost of manufacture. This paper reviews the most recent trends and advancements in sputtered HEA coatings, thin film research, and development. Firstly, HEA coating and thin films were introduced. Then, a look at sputtering technologies and procedures is presented, followed by a summary of recent research on sputtered HEA thin films, properties, and applications. From reviewed literature, it can be deduced that HEAs that include the full nitride element have greater mechanical and elastic properties, and HEAs generally have the potential for structural, industrial, biomedical, and energy applications. Finally, it is suggested that new stable HEA films and coating research initiatives with various materials be undertaken to widen its applications.

In this work, accelerated thermal aging at different temperatures was performed on high-density polyethylene (HDPE) bottles and specimens for food packaging. The degradation of HDPE was followed macroscopically by tensile and compression tests to evaluate the decrease in mechanical properties. The data obtained from these tests are used to calculate a new static damage law and the life fraction of this polymer. A prediction of the lifetime of HDPE was determined by thermogravimetric analysis (TGA) in dynamic mode. The evolution of the crystallinity rate during accelerated thermal aging was carried out using FOURIER transform infrared spectrometry (FTIR). The results obtained show a remarkable degradation of the mechanical properties in traction and compression by calculation of the static damage, and the physical and chemical properties by the analysis of the rate of crystallinity as well as the prediction by the law of Arrhenius.

The dynamic behavior of the cylindrical shell can be predicted by more simplified beam models for a wide range of applications. The present paper deals with finding design conditions in which the cylindrical shell performs like a beam. Employing the Hamilton’s principle, the governing equations are obtained using both Donnell-Mushtari and Flugge shell theories and the analytical solution is obtained for long cylinders with simply-supported boundary conditions at both ends. Then, by equalizing the shell and beam vibration frequencies, the shell-to-beam transition conditions are obtained for both theories. To account for the effects of shear distortion and rotatory inertia of the shell, the finite element method is applied to find the best transition conditions with less approximating assumptions. Finally, the effects of boundary conditions on the transition parameters as well as the frequency response are studied. The obtained conditions simply define that if the shell can be assumed as a beam in any specific geometrical and material conditions.

This paper investigates the shear strength and failure modes of steel-concrete-steel (SCS) sandwich composite member with Engineered Cementitious Concrete (ECC) and explores the influences of various shear connectors such as headed stud and bolt on shear behavior of SCS sandwich composite member by carrying out push-out testing program. Based on the test results in this study, the failure modes and the load-slip behavior of the specimens are investigated. In addition, the experimental results on the shear resistance of the headed stud connector with various connector spacing and numbers of connector is compared and explored.

In reality, concrete structures are normally under various loadings, and results of different studies have shown that cracks in these structures and their materials, due to their nature as well as the loading type, do not develop along the crack plane (pure mode I); rather, they expand under mixed modes, making the crack growth studies under these modes a very important issue. In the crack growth phenomenon, the fracture toughness is a very effective parameter usually calculated by ENDB samples because they are easy to handle. In this study, several samples were made by changing the maximum aggregates size (dmax = 9.5, 12.5 & 19 mm) and the amount of hooked-end steel fibers (SF = 0.1, 0.3 & 0.5%), and tested under different loading modes (pure/mixed modes I and III) using the strain control jack device. According to the results, the lowest fracture toughness belonged to pure mode III, aggregates with dmax = 12.5 mm performed better in the self-compacting concrete reinforced with steel fiber, Also, the results show that the increasing trend of steel fibers does not have a positive effect on the fracture toughness performance.

The interconnected usefulness of titanium grade 5 is amplified by the improved mechanical ability and sustainable applications in various industries like the aerospace, medical industry and many more. Despite the profound properties of Ti6Al4V, it is worthy of intellectual study to investigate the possible performance improvement of the material for better operational application. This study adopted the use of RF magnetron sputtering to deposit the target on the substrate material under varying temperatures and deposition power. A total of four samples and control were analyzed for a surface morphological examination and post-sputtering chemical compositional analysis via SEM (scanning electron microscope) and EDX (energy dispersive x-ray analysis). Further investigation on the samples' crystallites was done using XRD (X-ray diffractometer). The SEM images showed low agglomeration and most of the samples were void of pores, cleft and crevices, which implied homogeneous distribution of the target (Inconel thin film) on the titanium substrate. The EDX of the Inconel coated titanium samples revealed elements such as Ti, Si and C, which are beneficial to the properties of the materials. The XRD profiles of the Inconel coated titanium samples disclosed intensities of high peaks, which indicated stability, chemical and microstructural homogeneity of the thin film.

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.

The behavior of clay minerals in expansive soils causes them to exhibit shrink-swell characteristics, making them unsuitable for engineering purposes in their natural state. To address this problem, researchers conducted direct shear experiments using fly ash as an admixture and black cotton soil as an expanding soil to explore the strength parameter. The experiments were conducted with varying amounts of fly ash ranging from 2% to 20%. Two arrangements of test series were made, and in the principal series, tests were made utilizing five unique densities and comparing dampness contents. The outcomes showed that the point of inside grating and union expanded directly up to the ideal dampness content and most significant dry thickness before diminishing. The subsequent series showed that the end of inward rubbing grew straightly with the expansion of fly debris admixture, yet attachment reduced after 10% admixture. The decrease in shear strength was because of the diminished passion, as the fly debris' cohesionless attributes took over as the admixture rate increased above 10%. Based on these findings, adding fly ash in small quantities to black cotton soil is recommended to avoid weakening it.

Since the late 80’s the Structural Analysis Research Group of the Instituto Superior Técnico (IST) has been involved in the development of non-conventional finite element formulations in order to overcome some of the limitations associated with the use of the CFE method and to develop high performance numerical tools for the analysis of structural engineering problems. Several alternative models for the linear and non-linear structural analysis have been developed using hybrid and mixed models techniques. These works are summarized in this paper, in which their past and future applications of this formulation in non-linear analysis of structures are fully detailed.