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Purpose “V-bending” is the most commonly used bending process in which the sheet metal is pressed into a “V-shaped” die using a “V-shaped” punch to form a required angular bend. When the punch is removed after the operation, because of elastic recovery, the bent angle varies. This shape discrepancy is known as spring back which causes problems in the assembly of the component in the modern aerospace industry. Regarding the optimization of spring-back accuracy, this research will illustrate the laws of the transition area (TA) of the nondeformation area (NDA) during the 90° “V-shape” bending process. Design/methodology/approach According to the traditional “V-bending” process to optimize the spring-back accuracy, the bent sheets are divided into deformation area (DA) and NDA. For this reason, the traditional “V-bending” process may prolong error to optimize the spring-back accuracy because NDA has a certain amount of deformation, which the researcher always avoids. Firstly, bent sheets are divided into three parts in this research: DA, TA and NDA to avoid the distortion error in TA that are not considered in the NDA in traditional theory. Then, the stress and strain in the DA and TA were discussed during theoretical derivation and some hypotheses were proposed. In this research, the interval, position and distortion degree of the TA of the bending sheet are used by finite element analysis. Finally, V-shape bending tests for aluminum alloy at room temperature are used and labeled all the work pieces' TAs to realize the deformation amount in the TA. Findings The bending radius does not affect the range of the TA, it only changes the position of TA in the bending sheet. It is evident that the laws of TA were explored in the width direction and gradually changed from the inner layer to the outer layer based on the ratio of width and thickness of the bending plate/sheet. Originality/value In the modern aerospace industry, aircraft manufacturing technology must maintain high accuracy. This research has practical value in the 90° “V-shape” bending of metal sheets and the development of its spring-back accuracy.

Purpose The demand for titanium alloys has received massive attention in the aerospace and automotive industry owing to their magnificent electrochemically compatibility and corrosion resistance, high strength at elevated temperatures and high strength-to-weight ratio. Although titanium alloy has impressive mechanical properties, they are challenging to machine or metal form due to its poor heat conductivity, high chemical reactivity, low modulus of elasticity, high friction coefficient and difficult lubricant that limits its application field and increases wear. However, surface treatment coating with the strong metallurgical bond between the titanium alloy matrixes is novel technique to resolve these challenges. This research will illustrate the influence of laser scanning power on the microstructure and tribological behavior of Nickel (NI)-composite claddings fabricated on TC4 titanium alloy to realize the strong metallurgical bond between the titanium alloy and NI-composite coating. Design/methodology/approach In this research, TiC/TC4 alloy nanocomposites were fabricated based on different laser power and temperatures. TC4 has been selected as a base material instead of TiC for the strong metallurgical bond between the titanium alloy matrixes. Then Ni-composite coating was used as the surface treatment coating on TC4 by laser cladding (LC) technique. The Ni-based alloy coating material powder is good self-fluxing, has high-temperature resistance and is analytically pure with 200 mesh, which can easily overcome the various challenges of titanium alloy. The chemical properties of Ni composite coating include 31.2% Chromium, 8%Titenium and 3.6% Carbon. The prepared surface treatment coating characterization and microstructure behavior are analyzed using optical micrograph, X-ray diffraction, scanning electron microscopes, energy dispersive spectroscopy and electron probe micro analyzer methods. Findings It is evident that at the beginning of the experiment, if the laser power increased, the quality of the coating increased. An optimal quality of the coating is found when the laser scanning power about 12.55 kJ/cm2. Further increased laser power diminished the quality of the coating because the material plasticity had deteriorated. The TiC ceramic particle reinforced phase is dispersed into a two-phase solid solution of β-Ti and γ-Ni. The micro-hardness of the used coating is greater than the base alloy. Originality/value This research has practical value in the modern aerospace and automobile industry to increase the application of titanium alloy.

Thermal energy storage system is one type of the system used to store the energy in different industrial applications. Thermal performance of the system is important to analyze when it has been operated with nanofluids. There is lot of energy is wasted from many process which can be utilized for the another process such as to preheat the water. In the present paper, the effect of water based nanofluids is studied to store the energy and results have been compared with base fluid. It was observed the nanofluid have more capacity to store the energy as compared to the base fluid because of it superior thermal transport properties. The pressure drop is also slightly higher than of base fluid. The thermal storage capacity of the system is significantly increased when it has been used with nanofluids as compared to base fluid under the same operating condition.

Regarding the complexity of energy consumption (EC) mechanisms and unpredictable EC in the additive manufacturing (AM) process, this research illustrates the laser cladding system's EC modelling and analysis method. Initially, according to the laser cladding system's working principle and EC characteristics, it is divided into five subsystems. Then, the energy consumption model (ECM) of each subsystem and the ECM of the whole laser cladding system are obtained through theoretical and experimental analysis. Finally, the ECM and specific EC were analysed in the cladding experiment. In this research cladding matrix and cladding material are both 316L Stainless steel. The results showed that the errors between the prediction results of EC and specific EC and the experimental measurement results were 1.37% and 2.17%, respectively, which indicate the accuracy and effectiveness of the model. The model has practical value in predicting the laser cladding system's EC, improving the process route, and achieving green development. The proposed method can also provide a reference for the EC research of other AM technologies.

The main goal of sustainable development is to engage the public in setting the groundwork for developing profiles based on carrying capacity assessments. Since industrial projects are located in traditional, non-industrial zones, the broad human resource development program includes environmental research, education, and training to build technical and practical skills in the country-based and scientific statistics system data gathering. It is noteworthy that the examinations were conducted sporadically and that the research did not correspond to the pollution level in Bangladesh's waterways. Therefore, it is essential to conduct a methodical examination that may offer a complete picture of river pollution so that appropriate preventative actions can be adopted to safeguard against pollution threats. Bangladesh has many environmental issues, including dirty air from various vehicles, unhealthy water, accumulating urban waste, untreated sewage, interior air pollution from wood smoke, and usage of fad-driven contemporary materials in homes. Each of them contributes more to the destruction of the environment. With the current trend of population growth followed by the construction of companies to suit their wants, such a situation may worsen. Hazardous gases, dust particles, or liquid effluents are the waste products emitted from industrial sources. These discharges are full of harmful chemicals that pollute aquatic ecosystems, disrupt the local biota, and eventually harm living things and associated flora and animals. As a result, studies were conducted, including the physicochemical characterisation of sugar refineries, distilleries, and other rivers that receive such effluents. These characteristics of subsurface water were also taken into consideration throughout the inquiry. This research will be anticipated to offer proper preventive methods for preserving the purity of the Bangladeshi rivers.

Electrical discharge machining (EDM) is used in die making and aerospace industries. This paper presents the performance study of the conventional EDM when used with powder mixed dielectric. Copper, graphite and mix (copper and graphite) were used. Pulse on, pulse off and current are the parameters which were varied at three levels. Copper, graphite and tungsten-copper were used as the electrode. The material removal rate and tool wear rate are assessed using design of experiments.