The main goal of this research is to compare the various optimization strategies (Response Surface Methodology, Taguchi, and Teaching Learning Based Optimization) for orthogonal turning of Hard to Machine materials. The workpiece material in this work is Ti6Al4V alloys. After selecting cutting speeds in the High-Speed Machining range, orthogonal turning tests are performed on the material for a specific combination of machining parameters – Depth of Cut, Cutting Speed, and, Feed Rate. A Lathe Tool Dynamometer is used to record the cutting forces from the trials. After combining Johnson Cook Material and Damage models, a comprehensive Finite Element Model is created to model the Orthogonal Turning of Ti6Al4V alloys. Experiments conducted previously validate the developed model. Three different strategies, namely RSM, Taguchi, and TLBO, were used to optimise machining parameters for minimal Cutting Force. The approaches are compared for the best combination of machining parameters and the best Cutting Force value. Analysis of Variance is used to study the impact of machining factors on Cutting Force.

This article studies the mechanical characterization of impact loads on polyamide fibers. Using synthetic ropes in mooring systems, these are subject to static loads, but dynamic loads are also expected. One of the dynamic loads that can occur on cables are sudden loads, which makes the analysis of impact loads important. In this study, impact cycles were applied to polyamide multifilaments until rupture with different impact masses, and considering the conditions: dry, after 6 hours of immersion in water and after 24 hours of immersion in water. The analysis of the immersed conditions allows us to interpret the plasticizing effect that moisture exerts in polyamide, through loss stiffness in the rupture test. The results show that the increase in immersion time represents decrease in the breaking strength, and also in the resistance to impact cycles. A curve parameterization is proposed that relates the number of impact cycles and the percentage of Yarn Break Load used in the impact, getting through the coefficient of determination the best model. For force versus time graphs, obtained in each impact cycle, the energy dissipation in the multifilament can be observed in two main mechanisms: the first is the elastic deformation in form of ricochets, the second is the plastic deformation by stretching/elongation. The force-time graphs of impact cycles and the number of impact cycles to failure are measures that show performance for impact dynamic loads. Attention should be the plasticizing effect caused by water, as it reduces the static and dynamic mechanical strength of polyamide.

Ratcheting is a second failure mode in low cycle fatigue loading where plastic strain accumulates in each cycle. It is difficult to precisely estimate component deformation due to the complexities of cyclic hardening. In order to study the deformation, all types of hardening rules must be determined priorly. In this study, the determination procedures of combined hardening parameters are presented using Abaqus software. The experiment data of API-5L X80 from the past research have been utilized. Lastly, the different inputs of non-linear kinematic hardening choices are analyzed and presented.

The article presents an analysis of the stress state of workpieces during upsetting of workpieces with an additional shear. For the analysis, the slip line method and the finite element method were used. A schematic diagram of upsetting in dies with “floating” elements, contributing to the implementation of additional shear, reduction of barreling, inhomogenous deformation and contour tensile stresses, is presented. The analysis of the research results showed that during upsetting of workpieces with additional shift forces, tensile stresses on the side surface of the workpieces decrease, which excludes the appearance of cracks on the side surface of the samples, especially when processing low-plastic alloy steels and alloys, and also reduces the barreling of the side surface.

In this study, Carbon, Glass, and Aramid fiber reinforced composite and their hybridized forms were fabricated using five different stacking sequences of the fabrics. Using the Vacuum Assisted Resin Transfer Molding (VARTM) procedure, epoxy resin was injected into these fabrics and allowed to cure at room temperature. From these five stacking sequences, a standard specimen with four different orientations viz. 0/90°, 15/75°, 30/60°, 45/-45° orientations were obtained using the Abrasive Water Jet Machining(AWJM) Process. The influence of stacking order and fiber orientation on tensile and flexural properties of composite was investigated. From the result of tensile testing, the highest and lowest tensile strength values were observed for neat carbon fiber reinforced composite at 0/90° orientation and at 45/-45° orientation respectively. The highest flexural strength was achieved in a hybrid combination of two layers of carbon, glass and aramid fabric for 0/90° whereas the lowest flexural strength was found in glass reinforced composite for the 45/-45° orientation.

Tendons transmit forces from muscles to bones through joints. Typically, tendons and muscles work together to innovate a motion. In addition, tendons are often subjected to much higher stresses than the muscles that they serve in any given action. As a result, tendons are susceptible to injuries that may lead to a permanent dysfunction in joint mobility due to the fact that the scar tissue that forms after healing often does not have the same mechanical properties of the original tissue. It is therefore very important to understand the mechanical response of tendons. In this paper the performances are examined of two viscoelastic standard nonlinear models in modelling the elastic and plastic behaviour of the tendon in the light of a well-known hyperelastic Yeoh model. The use of the Yeoh model is more for validating the performances of the viscoelastic models within the elastic region than for comparison purposes. The Yeoh model was selected based on its superior performance in modelling the elastic phase of soft tissue, as reported in previous studies, combined with its simplicity. The results show that the two standard nonlinear solid models perform extremely well both in fitting accuracies and in correlating stress results. The most promising result is the fact that the two standard nonlinear models can model tendon behaviour in the nonlinear plastic region. It is also noted that the two standard nonlinear models are physically insightful since their optimisation parameters can easily be interpreted in terms of tendon elasticity and viscoelastic parameters.

The production of ceramic creates scrap material that is often wasted. The aims of this study are to know the influence of size and material on scrap material and the role of accounting in managing the environment. The results show that product size and material used together have an effect on scrap material. Partial testing shows that only materials used have a positive and significant effect on the emergence of scrap materials. The accounting treatment is done by debiting Cash IDR 5,258,753.99 and crediting Work in Process-Raw Material Cost IDR 5,258,753.99. The cost of goods manufactured of ceramic products after accounting treatment for scrap material is lower than before. The selling price also decreased for the same product. The operating profit will increase IDR 5,013,038.64 (use original selling price) and decrease IDR 1,272,112.67 (use selling price after treatment for scrap material). The emergence of scrap material causes environmental problems. Environmental accounting overcomes this by removing scrap material from its place. The transfer is done by selling at a price of half the standard price. The proceeds from the sale are treated as a deduction from the cost of raw materials in an account in the Work in Process-Raw Materials Cost credit.

Reinforced concrete wall critical zones are the responsive areas of dissipated earthquake loads. They are formed in the connection of the wall panels and the fixed restraints. The longitudinal and transversal steel reinforcements with certain spacing are designed according to the required nominal strength at the connections. Under certain conditions, the reinforcement distance becomes very tight, making working on castings using normal concrete difficult. This condition also occurs in boundary elements consisting of longitudinal and transversal reinforcements in tight spaces. A concrete material that flows easily and solidifies itself is required to avoid segregation. One type of this material is Self-Compacting Concrete (SCC). The SCC performance as a wall panel material that withstands gravity and cyclic lateral loads still require further research. This study aimed to analyze the hysteretic performance of reinforced SCC wall panels with variations of shear reinforcement in resisting cyclic lateral loads. The analysis used software based on numerical analysis. The drift ratios, hysteretic curves, stress patterns, ductility, and stiffness of the wall panels were analyzed. The SCC wall panel with ordinary shear reinforcement resisted lateral positive and negative loads of 152.32 kN and 143.09 kN, respectively. In comparison, the wall panel with boundary elements and tighter shear reinforcements could withstand the positive and negative lateral loads of 187.62 kN and 145.98 kN, respectively. The SCC wall panel reached the best ductility of 21.38 with ordinary shear reinforcement because the yield occurred faster than in other wall panels. The results showed that the boundary elements and shear reinforcements of reinforced SCC wall panels affected the performance in resisting cyclic lateral loads.

The increasing demand for good and improved polymeric composites has led to a surge in the number of researches on hybrid composites, strengthened and enforced with the natural fibres. This paper mainly analyses and presents the attributes of hybrid composites made from natural fibres and carbon nano-tube (CNT) nanoparticles. A novel hybrid composite considered in this research includes kenaf and coir fibres with CNT nanoparticles embedded in an epoxy matrix. The proposed hybrid nanocomposite’s elastic features are calculated by using different analytical models like Chamis, Mori-Tanaka, Nielson elastic models etc and also with the help of Representative Volume Element Analysis (RVE). The content of fibre volume is varied in four different samples and it is found that upon varying the content of fibre volume, the mechanical properties like longitudinal modulus and transverse modulus got affected. The results evaluated from different analytical models are observed to be in good agreement with each other and also with the results of RVE analysis.