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This paper introduces the concept of remotely-driven smart actuator utilized by electro-active paper (EAPap). The feature of remotely-driven smart actuator offers unique performance and application capabilities and exploit many of these unique capabilities. Since the microwave-driven actuator does not require carry-on-battery, ultra-lightweight, and distributed micro size actuators can be made. A dipole rectifying antenna (rectenna) array receives the microwave and converts it into a DC power. Recently, cellulose based paper has been came across as an lectroactive paper (EAPap) material so as to be used as artificial muscles for biomimetic insects. Since the power requirement of EAPap is less than the safety limit of microwave power in air, the EAPap actuators can be driven by wireless microwave power. This idea is useful for specific applications that require multifunctional capabilities such as smart skin, ultra-lightweight space structures, micro robots, flapping wing for insect-like flying objects and smart wall paper as well. Current research status along with its issues is addressed including a hybrid actuator of EAPap and conducting polymers that will enhance the performance of the actuator.

Effect of metal modification to carbon paper as the anode of mediator-aided yeast-based microbial fuel cell on the cell performance was investigated using methylene blue as an exogenous mediator. The modification was conducted using a sputtering technique by depositing Co or Au thin layer, 30 nm. The electrode performance was evaluated by measuring the electrode potentials and the fuel cell power output. The metal modification significantly increased the mediator-aided MFC performance.

Effect of modification of carbon paper with a thin layer of cobalt or gold on the performance of yeast-based microbial fuel cells was investigated. The modification was conducted by depositing Co or Au thin layer with different thickness, 5 nm and 30 nm, using a sputtering technique. The electrode performance was evaluated by measuring the electrode potentials and the fuel cell power output. The Co modification significantly increased the performance of the fuel cell, while the Au modification inhibited the performance. SEM observation indicated that the adhesion density of the yeast cells on the electrode surface was affected by the metals. It was confirmed that the electron transfer took place through the surface confined species at the mediatorless anode.

Compressive performance of honeycomb paperboard with different number of paper-cores had been analyzed to meet the need of honeycomb paperboard produce. First, the models were built after buckling theory analysis. Dynamic characteristics of nonlinear collapse process under axial dynamic load were analyzed in the FEA software. It was indicated that: the collapsing process was divided into four parts: linear elastic phase, elastic-plasticity phase, plasticity collapse phase and densification phase. When the number of cores increased, the models had a bearing up on compressive strength. At last, the compressive performance had been verified by experiment.

A new effective fabrication module was developed to mediate the problem of the low yield of Indium-tin-oxide (ITO) nanostructures deposition uses micro electroremoval technology and a design of twins-cylinder tool as a precision etching process to remove the defective Indium-tin-oxide (ITO) from the optical PET diaphragm surfaces of digital-paper displays. For the removal-process, a small gap width between the negative electrode and the workpiece (optical PET diaphragm) surface corresponds to a higher removal rate for the ITO. A small diameter of the anode or a small diameter of the cathode of the twins-cylinder tool provides large electric current density and takes less time for the same amount (20 nm) of ITO removal. High rotational speed of the twins-cylinder tool the discharge mobility and results in improving the removal effect. Providing enough electrical power can uses fast feed rate of the optical PET diaphragm combined with a fast removal rate for ITO. With increasing in current rating, pulsed direct current can improve the effect of dregs discharge and is advantageous to associate with the fast feed rate of the optical PET diaphragm. By establishing a recycling process using the ultra-precise removal of thin-film nanostructures, through the micro electroremoval and the twins-cylinder electrodes requires only a short period of time to remove the ITO thin-film easily and cleanly. The optoelectronic semiconductor industry can effectively recycle defective products, minimizing both production costs and pollution.

The pigment electrophoresis dispersion has been the widely used system. It is, however, worth of attention if molecular dye, instead of pigment, can be used in the display of electronic paper. By carefully selecting the structure of dyes, especially the metal complex dyes, and studying the properties of the prototype display. It was found there are about 15 dyes electrophoresis and some dyes display well. The dyes ink with good stability during electrophoresis when the electrode was protected, while the response time is about 300 ms, and the concentration is an important factor on the display optic density. The displaying principle of dye ink was studied too.

Epoxy ecocomposites reinforced with recycled paper (rP) and nano-kaolinite (nK) have been synthesized. The effect of seawater soaking on the flexural and impact properties have been characterized. This new but cost-effective approach has been developed to improve the physical and mechanical properties of polymeric materials without adversely affecting their processing characteristics. The micromechanisms of toughening and failure processes are discussed.

The global market size for Additive Manufacturing is predicted to be around USD 20 billion by 2025. The question arises whether conventional machining such as Computer Numerical Control (CNC) should be replaced by Additive Manufacturing (AM). The results presented in this paper are the outcome of an ongoing study. The overall objective of this study is a decision tool to decide which manufacturing route to adopt from a sustainability perspective. This paper will discuss the first phase of this study looking at the mechanical performance, cost and complexity of parts produced from AM and CNC. The results show that small parts are cheaper to fabricate by AM regardless of part complexity, whereas large, simple parts are cheaper to fabricate by CNC machining. These results might help in identifying manufacturing limitations of AM process in terms of mechanical performance and cost. These results will serve as inputs into a decision-making framework to decide on the most effective manufacturing route based on desired application such as in the spare parts in oil and gas industry.

Additive Manufacturing (AM) is a technique in constructing components from a CAD model to a finished product. This is done by depositing molten material at a specific coordinate and height. This is done continuously until the finished product has been produced. Both FDM and PLA are well-known technology and material in the AM field. Optimizing the parameters will surely provide a good reach for hobbyists, researchers, and academicians. Optimization is a process concerned with the identification of the best possible value/condition for a certain parameter. Most research papers optimize a response/factor at a time given that less than five parameters are being studied. This paper aims to optimize three mechanical properties such as strength, elongation, and modulus of elasticity. This response was optimized through seven (7) benchmark parameters conducted in mixed levels (a combination of two and three levels). This paper was able to identify the optimum level per parameter, provide insight into the significant contributors affecting the target responses, and lastly, provide a contour plot to serve as a reference of AM end-users.

In practical engineering applications, it usually gets the expected value of the ultimate side friction of concrete piles by the empirical parameter method. The expected value of the ultimate side friction of concrete piles cannot achieve maximum optimization due to the complexity of formation conditions and the lack of experience of technicians. To accurately obtain the ultimate lateral friction resistance of piles in homogeneous soil layers, optimize the standard value of pile ultimate lateral resistance, ensure construction safety, and save construction costs, the research method combining theoretical derivation and on-site measurement data validation was done in the manuscript. Based on the shear strength of the pile-soil interface of different materials and the shear performance of the soil around the pile, a calculation equation for the standard value of the ultimate lateral friction resistance of concrete piles in different homogeneous soil materials was derived and applied to the equation for calculating the ultimate bearing capacity of foundation pile and the axial force of pile. Finally, based on an engineering example, the calculated results were compared with the measured resultsThe research results show that in thick coarse-grained soil, as the foundation pile is short, the ultimate bearing capacity of a single pile obtained using the calculation equation deduced in this paper is less than that obtained using the empirical equation provided by the national code. In a deep cohesionless homogeneous soil material, the concrete pile shaft axial force calculation using the pile shaft axial force calculation equation deduced in this paper is close to the measured value when the foundation pile bears the ultimate load; the proposed new method has good application value.

This article will try to implement an ecological pavement using paper cellulose obtained from the recycling process of non-toxic sanitary waste, in order to combat environmental problems and make better use of this desire, thus preventing its increase in dumps or landfills. Therefore, tests were carried out to determine the optimal percentages of recycled paper cellulose that should be added to obtain an asphalt mixture that meets the proper parameters to be used, in this case focused on the realization of bicycle lanes. This would represent a benefit for the environment, which aims to create awareness in people, showing them the type of civil works that could improve from an adequate recycling process. Our study implements the RAMCODES methodology, which optimizes the production of briquettes, considerably reduces their number and guarantees a good result, giving way to this methodology that can be used in the future for new studies and that these are carried out in a faster and with guaranteed results.

Architecture is rapidly developing with new technologies, materials, and a desire to create more efficient and sustainable cities. It is becoming increasingly important in improving people's lives and cities by providing sustainable, more comfortable, and more aesthetically pleasing living and working environments. Architecture and construction materials have been developing rapidly in recent years, dramatically improving the quality of life and the look of cities. From energy-efficient building materials to smart management systems. ETFE is a fluorine-based plastic polymer that has become increasingly popular in the construction of modern buildings because of its lightweight and durable properties. This paper examines the characteristics of ETFE (ethylene tetrafluoroethylene) material in architecture and its application benefits in construction projects taking the Al-Abdali shopping center an example, which is located in the capital city of Amman, Jordan, where sustainable materials have remarkably grown in the past few 20 years. The study employed a direct observation method to assess the importance of ETFE sustainable material in the shopping center in Amman. Data from previous research and studies that are mainly related to construction materials were also included to build the base of this study. The study's results provide both an overview of ETFE material characteristics in architecture and an insight into its application in the chosen case in Amman. This paper contributes to understanding ETFE material characteristics, its application in architecture, and its potential for future use in similar projects.

Cellulose and lignocellulose have great potential as nanomaterials because they are abundant, renewable, have a nanofibrillar structure, can be made multi¬functional and self-assemble into well-defined architectures. New methods for liberating these materials, including nanodimensional cellulose fibrils, macromolecules and nanominerals will be needed in order to use the techniques developed for other nanomaterials as platforms for creating new wood-based materials and products. Research findings showed promising results in application of nanotechnology at different aspects of papermaking. Electrospinning; chemical treatment followed by mechanical techniques; or mechanical isolation methods were applied by different research groups to prepare cellulose nanofibres.

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The SiC/Si multilayer composites were fabricated successfully by reaction sintering method with normal stacked papers as the raw materials. Paper was cut into rectangular sheets and stacked, then infiltrated with phenolic resin to get a laminar structure. This paper /resin laminar composite was transformed into porous carbon with laminar structure after heating at 800 oC for 2h in N2 atmosphere. Finally this porous laminar carbon was reheated with silicon powder at 1450-1650oC for 1-2h in a vacuum furnace and SiC/Si multilayer composites can be obtained through the in-situ reaction between carbon and liquid silicon. The microstructure, reaction mechanism, phase composition and mechanical properties of these multilayer composites were researched. The final material shows a distingished laminar structure with alternating arrangement of SiC thick layers and silicon thin layers. SiC layer was composed by beta-SiC and a little of free silicon and carbon not reacted. The capillarity infiltration and in-situ reaction of liquid silicon act key roles in this process. Higher strength and non-catastrophic failure mode for this material were observed.

Problems with corrosion in boilers and their parts can be solved by the application of different nickel alloys like 622, 625 or 686 by a variety of welding processes. This solution is used mostly in Waste-to-Energy plants or biomass stations burning waste wood, but it can also be found in the recovery boilers used in the paper industry. The most common material grades include low alloyed boiler steels like 16Mo3, 13CrMo4-5 and 10CrMo9-10. When there is a need to increase steam temperature and pressure more complicated alloys to become a natural choice. This paper focuses on the fabrication experience of welding of 7CrMoVTiB10-10 base tube with Inconel 625 weld overlay and presents a welding solution of matching filler metal used for root pass and S Ni 6625 filler metal for a fill-up and the cap performing a full strength weld without the need of overlay peeling and manual tie-in overlay. This method of welding saves a lot of time during execution in the workshop and on-site during installation and assures much better quality in the end. All examinations were performed to allow welding procedure qualification according to ASME and EN standards.

When investigating the heterogeneous properties of welded joints, mechanical testing of certain Heat Affected Zone (HAZ) regions, using standard approach test specimens, is very difficult or sometimes even impossible. Inability to precisely position and extract mechanical test specimens, even ones of the subsize dimensions, from the narrow HAZ regions is a limiting factor in the mechanical testing implementation. Detailed investigation of the HAZ is made possible by the use of thermo-mechanical simulations on the Gleeble welding simulator. In scope of this paper several characteristic HAZ microstructures of S690QL grade High Strength Steel (HSS) are being simulated. Multi-pass welding simulations are done on special 10x10 mm square section bar specimens in order to reproduce thermal gradients and characteristic microstructures at any location in a weld. Such simulated HAZ microstructures are of a sufficiently large volume, with homogeneous and repeatable properties, that standard specimen methods for mechanical testing can be readily implemented. Metallographic optical examinations, as well as hardness measurements were done initially. Mechanical properties are focused on determining stress-strain curves for each characteristic weld region. The paper investigates whether the mechanical properties of Gleeble simulated hard-soft combined HAZ regions are better in comparison to exclusively hard or soft HAZ regions. The obtained results can subsequently be used for the material model development.

Concrete the spirit of the infrastructures and it’s a combination of cement, water and coarse aggregate, fine aggregate and add mixtures. Sand and cement is consider as critical material in significant mix design due reality that collecting of cement and uncovering sand is impacting out. In case consider concrete the manufacturing of it release out CO2 and other green house gases and in other hand sand expulsion furthermore is lead us to stream bed declination, so most ideal choice for the both of materials ought to be taken vital notes. Through this paper an imaginative focus on utilization of Pareva Dust as a replacement to concrete and Quartz Sand as replacement to sand at different level (5%,10%15%) is utilized and assist with getting's mom earth. Through this examination paper study is given for the mechanical and quality properties of which guide as choice in concrete.

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Several techniques based on ultrasound have been proposed for non-destructive evaluation (NDE). It has been widely applied in many fields such as medicine, mechanical, and construction, especially for the detection of cracks and flaws in structures and for the identification of material properties, which is capable of performing tasks to provide quick measurements while guaranteeing great accuracy. In this paper, we have developed the technique of ultrasonic transmission by water immersion as an alternative technique to study the propagation of ultrasonic waves in two structural materials: wood and wood protected by liquid paint (cement). Overall, the application of the transmission technique by change of the angle of incidence enables the demonstration of the experimental dispersion curves for the ultrasonic modes within the plates and allows the investigation and characterization of the function of the paint system (cement) in the wood plate.

The paper presents a mathematical model for calculating cutting forces during the machining of 16MnCr5 steel using the Sandvik CNMG 120408 16P25T tool. The modeling process involved the use of a test rig constructed based on the 16Д25 machine, which enabled the measurement of real values of spindle speed, longitudinal feed, cutting depth, and cutting forces. The results transmitted to a computer through the LTR-EU-8 workstation, equipped with galvanic isolated LTR modules and a synchronization interface. Based on the experimental results, the theoretical model demonstrated a deviation from actual measurements of no more than 4.72%. The study provides evidence that the cutting force calculations commonly presented by leading tool manufacturers are inherently overestimated. he difference in cutting forces can be 9%.

A deep understanding on the intermixing of components in hybrid yarn or composite structures is decisive in order to develop hybrid structures with desired properties. This paper presents the development of a versatile procedure for the determination of the degree of fiber mixing in yarns and composites based on microscopy images auto-segmented by a neural network. The procedure is based on the quantification of blend irregularity values and blend homogeneity. For this purpose, functions of spatial point patterns analysis have been used to investigate the blend uniformity of yarn and composite cross sectional areas. The results show that the trained neural network model for segmentation of images has an accuracy of 92 %, indicating that the method is capable of accurately assessing the location of fibers in hybrid struc-tures. The results of the spatial point patterns analysis reveals a correlation between the blend value and the properties of yarns and composites. The proposed method provides a fast and reliable way to evaluate the hybrid structures, which could be used as a tool for quality control and process optimization.

In the last twenty years, the manufacturing of titanium and its alloys for commercial use continued to expand. As this material has several very advantageous properties, leading to increasing applications in various industries, it is seldom used in mechanical engineering applications due to its tribological properties, which are unfavourable. The nitriding process is one of the most frequently used thermochemical processes designed to enhance the surface characteristics of titanium alloys and improve tribological properties. Various types of nitriding for titanium are studied, such as ion nitriding, plasma nitriding, laser nitriding and gas nitriding. This article provides a comprehensive examination of research papers on different advancements through a systematic literature review conducted in the period 2017-2023 about titanium nitriding for its process parameters, characteristics and functionalities of the product, particularly emphasising their contributions in surface characteristics and mechanical properties. The review seeks to offer an understanding of how the predominant processing factors, specifically temperature and time, affect the microstructure and the creation of novel phases. This review suggests a challenge for future researchers to investigate mechanisms of microstructure evolution and its impact on mechanical properties in conditioned environments to microhardness and ability to withstand rusting of titanium and its alloys.

Micro EDM is unconventional metal removing technique that is effective in machining hard-to-cut conductive materials. It has a big potential in modifying surfaces of metallic bone implants for better biocompatibility by providing proper surface topography to ease cell adhesion. However, it is still important to study machining performance. This paper investigates material removal rate (MRR) and surface roughness (SR) of micro WEDM on Ti-6Al-4V alloy. Three level Taguchi’s design was implemented to observe the effect of capacitance and gap voltage. Moreover, analysis of variance (ANOVA) and grey relation analysis (GRA) allowed to investigate contribution of each parameter and find their best combination for multiple output optimization. Results showed that highest MRR of 1.72*10-2 mm3/s can be achieved at 10 nF and 90 V values, while smallest SR of 0.309 µm can be achieved at 1nF and 90 V. In addition, the contribution and significance of capacitance on MRR and SR was considerably higher than the effect of gap voltage. Lastly, the optimal parameters for multiple output performance were calculated at 10 nF and 90 V values.

Transition metal dichalcogenides (TMDCs) nanomaterials, in particular Molybdenum disulfide (MoS2), have been employed frequently as a basis for flexible gas sensors due to their extreme sensitivity to gas molecules, super mechanical and electrical properties, and large surface area. This work aims to study the behavior of the flexible gas sensor made of 2D-MoS2 under exposure to nitrogen dioxide (NO2) gas at the part per million (ppm) level. The mono-layered MoS2 was successfully synthesized by Chemical Vapor Deposition (CVD). The formation of MoS2 layers was confirmed by Raman spectroscopy and Photoluminescence (PL). Two different gas-sensing devices were fabricated by transferring two MoS2 samples (obtained from two positions inside the CVD tube) onto paper substrates. Specifically, upstream sample Sup was obtained from an area near the MoO3 source, and downstream sample Sdown was obtained from an area far from the MoO3 source. Both sensors showed a good response to a concentration as low as (1.5 ppm) of NO2. Although a high response of 62.8% along with a fast response of 9 sec were recorded by Sdown, the sensor showed a slow recovery time of 42 sec. On the other hand, Sup showed good stability with an appropriate response of 36.8% along with a reasonable response time and recovery times of 20 and 27 sec, respectively. Such behavior could be accredited to the difference in the reactivity in both MoS2 samples. This work opens the way for further improvements in manufacturing MoS2-based flexible gas sensors.

Current research focuses on advancements and breakthroughs in the realm of smart textiles, with applications spanning various industries such as medicine and education. For producing flexible smart textiles, electrically conductive yarns (EC) are needed to transmit signals or as part of sensor systems. Mostly, these EC consist of a polymer core with an outer metallized layer. Using EC in contact with skin requires high reliability and safety, and thus, the EC must maintain their functional properties on a long-term scale under a range of different stresses. The electrical properties of EC deteriorate under mechanical stress applied during production or in-use through damage to the yarn’s surface. At present, there are only partially feasible solutions to protect the metal-layer of the yarn surface. Hence, this paper presents a newly developed non-toxic coating (NTC) to protect the EC surface. The NTC consists of an aqueous emulsion with polypropylene wax and oxidized wax. To determine the long-term stability of the coating, the produced yarns undergo comprehensive evaluation using a range of analytical techniques. The aim is to identify the optimal coating by exploring different equipment and parameters. Additionally, it is various test methods to gauge the durability of the newly developed NTC used and ensure its reliability over time. To characterize the yarn properties before and after the coating, light microscopy (LM), washing processes, mechanical resistance tests and resistivity measurement are conducted.

Motion capture, especially of the knee angle, is an important component for situational triggering of functional electrical stimulation (FES). One major disadvantage of commercial FES devices is their bulky design that prevents unobtrusive wearing in everyday life and limits the patient’s free choice of appearance. This paper presents an alternative approach of sensors for motion capture in form of textile-based strain sensors. These can be integrated in a FES system in form of functional leggings, which make the FES system suitable for an unobtrusive daily use. Textile sensors, especially knitted sensors have already proven to be very promising to detect tensile strain. In particular, weft-knitted strain sensors, which can be integrated directly into the clothing during the knitting process, have the potential to detect the knee angle and therefore derive the gait phase due to the bending of the limbs without disturbing the wearer unnecessarily. Different designs of the weft-knitted strain sensor and their influence on the measurement behaviour of the sensor have been investigated. The weft-knitted strain sensor can be directly integrated in the knee area of the functional leggings to be used as a soft trigger to initiate electrical impulses for FES.

In the research field of smart textiles, one main goal concerns quantifying environmental forces acting on the wearer's body since textiles, acting as the boundary between the two, are an excellent way of integrating sensors. Integrating strain and pressure sensors into wearables promises a simple way of monitoring a person's posture and forces acting on their body. Sensors relying on a capacitive measuring principle are highly suitable for this, as they are less sensitive to changes in temperature than resistive or inductive types. In this paper, textile-based capacitive sensors are produced by braiding conductive yarns with and without an electrically insulating TPU sheath. The produced sensors are analyzed in cyclic strain and compression tests. Moreover, their behavior under changing temperatures is tested to prove their resilience against environmental changes. To extend their capabilities from an integral measurement to a localized assessment of the strain, time-domain-reflectometry (TDR) is employed. Finally, the sensors are integrated into a flexible actuated bending beam, and their adoption for soft robotics is discussed. Strain is tested cyclically, showing good long-term stability. Pressure sensitivity is measured in a static compression test under increasing force. TDR is used to localize strain in two discreet sections of the sensor. Although strain could not be quantified through TDR, characteristic points in the measured response signal indicating the position of the strain were identified. Textile-based capacitive sensors are suitable for strain up to 10 % and pressure up to 8 N. The determined gauge factors are satisfactory, with strain sensors inherently having a higher gauge factor than pressure sensors. Furthermore, they display good long-term stability and no adverse reaction to changes in temperature. TDR is proven to provide localization of strain in flexible sensors.

The paper deals with the methods of software optimization of the concrete structure in terms of environmental issues, durability, and cost. It links to previously developed software tool that enables multi-criteria optimization of a 1 m2 one-way slab. A feasibility study focused on the optimization of larger structural units, and it analyses and compares methods of concrete structures optimization in terms of environmental impacts, durability, and life-cycle cost.

This paper deals with failure modes of a steel-concrete-steel sandwich loaded by pure in-plane shear. Current research together with the developed models imply that increase of reinforcement ratio leads to decrease of ductility and possibly to change a failure mode from yielding of steel in tension to crushing of concrete in compression which results in brittle failure. In order to give a reader basic information about in-plane shear behavior of a steel-concrete-steel sandwich, an analytical model is introduced. Japanese experimental program that researched a behavior of SCS panels with reinforcement ratio 2.3%, 3.2% and 4.5% is also shown. In addition to the effect of changing the reinforcement ratio, the experimental program also investigated the effect of the transverse steel plate on the ductility of test panels with a degree of reinforcement of 3.2%. The next chapter describes the methodology used by the author to model the individual parts of the model, the loads, and especially the method of supporting the model. This is followed by the presentation of the results of the analysis on the calibration and extrapolation models. Finally, a discussion is conducted on the agreement of the analysis results on the calibration models with the Japanese experimental results, followed by an evaluation of the analysis results on the extrapolation models. According to the results on the extrapolation models the critical degree of reinforcement at which a change in the failure mode of the structure occurs under in-plane shear loading is around 13%.

The paper deals with the problem of stress in the connection detail of vertical supporting structures with a flat slab and possible methods for its analysis. It mainly focuses on the problem of non-axial connection of columns and walls, which is typical for today's architectural designs. The parametric study compares the effect of the distance of the connected vertical support structures on reinforcement in the discontinuity region. Three different computational methods are used to stress analysis of this region - linear Finite Elements Method in SCIA Engineer software, 2D Strut-and-Tie Model and 2D non-linear Finite Elements Method in IDEA StatiCa software. The conclusion of the study is a comparison of the accuracy of different calculation methods and also a comparison of the solved design variants in terms of shear and bending stress and specific form of reinforcement.

When analyzing slender columns, the second-generation Eurocode FprEN [2] recommends the calculation of the bending moment envelope, which consists of both first-order and second-order moments. This paper presents the aforementioned calculation method for both braced and bracing columns, utilizing a comprehensive “general” nonlinear approach.

As a new trend in modern structural design, the high-performance steels are increasingly used in steel structures, due to their superior mechanical properties, which could have decisive impact on the resistance and deformation capacity of structural components. High-performance steels include stainless and high-strength steels. The higher proof stress of the high-strength steels allows using thinner sections and material economy for those structural elements that do not experience stability problems. Austenitic stainless steel shows a series of advantages, including low maintenance costs and an excellent toughness at low temperatures. But the main characteristic which matters especially in seismic design, is the higher ductility, larger strain hardening and elongation at fracture in comparison with carbon steels. In this paper, the analysis of the behaviour of 1.4404 austenitic stainless steel and of S690 high-strength steel, in comparison with a reference S235 mild carbon steel is presented. This paper presents the assessment of the monotonic and cyclic performance of these steel grades, as well as the failure pattern, in order to assess the potential use in structural applications.

3D-printed polymer component parts and spare parts are now being widely used in various applications. In this paper, the 3D printing technologies and materials for spare part production in several applications are presented. Some opportunities and challenges faced when using 3d-printed spare parts are also discussed. The acrylonitrile butadiene styrene (ABS) has mostly been used. And it was found out that the durability of the spare parts could vary depending on the application.

Rotary friction welding (RFW) is one of the most essential creations of modern technologies because it satisfies and compensates for the shortcomings of traditional welding methods. This paper presents a study on the impact of the annealing solution process on the joints of the rotary friction welding process in Al 6061 material and with a selection of the best parameter for the procedure. The quality of the weld-joints was evaluated by a series of experiments of measuring hardness, tensile strength tests and observing the micro-structures of the specimens to achieve conclusive evidence. The aim of these experiments is to carefully and precisely examine the impact of the heat treatment process on the welded joints’ physical properties and microstructure properties. The results show that the heat treatment does enhance the mechanical properties of the material, but it is essential to conduct experiments to find the optimized parameters; or else, the properties will decrease largely.

Aluminum materials are used in a wide field for household appliances, aircraft, cars, ships, and construction. This research aims to obtain a new material based on aluminum magnesium silicon (AlMgSi) alloy as an alternative material to replace the steel base material in the shaft propeller product. In this paper, we will use the die-casting method to investigate corrosion resistance and the microstructure of the propeller shaft with AlMgSi aluminum alloy base material. The main base material used is 6063 aluminum alloy, with variations in the addition of Si (1, 2, 4 wt%). Alloy Al6063 is heated to a temperature of 720°C to reach a complete liquid state. Then the temperature is lowered to 645°C, then the Si element is inserted into the heating furnace and stirred. Then the temperature is lowered to 615°C, then the Mg element is added, then stirred thoroughly by a mechanical stirrer. The rotational speed of the stirrer is 70 rpm and the stirring time is 240 seconds. They were then heated to a pouring temperature of 680°C. The mold is heated to a temperature of 265°C. Then poured into the mold and pressed 7 MPa. The cast is cooled at room temperature. Then the casting products were heat treated with a solution treatment temperature of 485°C for 3600 seconds and quenched. After that, the casting products were treated with artificial aging. The results of this study show corrosion resistance increases along with the addition of variations of Silicon. The highest corrosion rate was obtained by adding Si as much as 4 wt% of 511.28 mm/y. With the addition of variations of Silicon 0 wt%, 1 wt% and 2 wt% showed the corrosion rate of 173.35 mm/y, 201.60 mm/y, 233.49 mm/y. The microstructure shows differences in grain structure. materials with variations of si 0 wt% and materials with variations of si 0 wt%, 1 wt%, 2 wt% and 4 wt% have different grain sizes. The intermediate phase (Mg2Si) was mostly formed at Si 4% wt variation. So this study proves that adding silicon elements can increase grain sizes and refiner the propeller shaft.

This study presents a research paper on the influence of heat treatment on FSW in Al 7075 materials. A comprehensive investigation was used to examine the impact of crucial weld parameters on the weld quality, including strength, flexibility, corrosion resistance, and weld structure. Additionally, the influence of temperature and tempering time on the weld quality was thoroughly examined. A series of comprehensive experiments were carried out on a 2.5 m thick aluminum 7075 plate that was welded using the Friction Stir Welding (FSW) technique. The primary objective of these experiments was to methodically examine the impact of heat treatment on the welded plate's mechanical and microstructural characteristics. The samples underwent examination both before and during heat treatment. The macroscopic and microstructural characteristics were analyzed utilizing optical microscope, tensile testing, and microhardness assessment. The impact of heat treatment is noteworthy as it substantially reduces the weld hardness while enhancing its elasticity.

In this paper, a series of tensile testing on wire drawing SUS 304 were conducted in order to meet the required specifications, thus, it can be utilized on the aircraft fighter components to remain stable and avoid shaking or vibration when the engine is operated. The studied material is expected to be used on flank airframes to improve its strength, wear resistance, corrosion, and aesthetic appearance. Series of tensile test has been conducted with universal testing machine (1 tonne) with modified jig configuration according to ASTM E8. The specimens were made according to the manufacture requirements such as wavy pin and straight pin connecting rod. The wire diameter has been drawing into the final diameter, which is Φ8.0 mm. From the tensile tests, yielding 1165.8 MPa and 1588.1 MPa, respectively. It is observed that the strength of woven SUS 304 wire drawing has reached the required specification to be manufactured in aircraft fastener. Factor of safety up to 2.0 has been acquired to the studied woven SUS 304 wire drawing.

The Indonesian government is committed to reducing greenhouse gas emissions under the Paris Agreement. One form of this commitment is the program to replace diesel power plants with renewable energy plants in the electricity sector. Fossil-based diesel power plant operations have disadvantages, such as relatively expensive generation costs and greenhouse gas emissions. There are three renewable energy technology options as potential substitutes for diesel power plants: a solar photovoltaic (PV) power plant integrated with a battery energy storage system (BESS), a small-scale geothermal power plant, and a micro-hydropower plant. This paper will analyze the prospects of each technology option based on its economic and environmental impact. Various technical parameters, including renewable energy potential and intermittent factors, as well as economic parameters such as investment and generation costs, are important factors for selecting prospective renewable energy generators. The analysis was carried out by calculating the levelized cost of electricity (LCOE), CO2 emissions, and oil fuel consumption for four different scenarios. The results of the analysis show that replacing the diesel power plants with micro-hydropower plants can reduce LCOE by 0.24 USD/kWh to 0.12 USD/kWh. The use of a solar PV power plant integrated with a BESS has the most potential to reduce CO2 emissions, which account for 54% of emissions from diesel power plants. Meanwhile, the potential for oil fuel reduction from this program can reach an annual average of 0.85 million kl.

This paper aims to investigate the effects of adding and increasing the concentration of halloysite nanotube (HNT) to a cellulose acetate (CA) membrane which is produced through non-solvent-induced phase separation via hand casting. Different characterization tests are performed on the nanocomposite samples: Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Fourier Transform Infrared Spectroscopy (FTIR), and Atomic Absorption Spectroscopy (AAS). The addition of the filler itself increases the presence of peaks and valleys on the surface of the nanocomposite membrane. The 5% HNT nanocomposite membrane has the largest peaks and valleys-both in size and number. Using the following contact times: 2, 4, and 6 hours, the adsorption capacity of the CA-HNT membranes is obtained with the aid of AAS results. The 5% HNT sample leads to a nanocomposite membrane with a higher adsorption capacity relative to that of a pure CA membrane.

When using the coat hanger die method for co-extrusion, the biggest challenges often involve maintaining the uniformity of the velocity distribution at the outlet of the die and ensuring the stability of the interface plane. This paper investigates the effect of different cross-section of feed channels connected to the coat hanger die on the velocity and pressure distribution of the flow at different parts of the die. Co-extrusion of LLDPE (Linear Low Density Polyethylene) and HDPE (High Density Polyethylene) polymers is simulated using ANSYS software 2020 R2 for coat hanger die design with rectangular and circular cross-sections inlet geometry; the results are compared for Carreau-Yasuda model to observe the result differences between rectangular and circular coextrusion channels connected to coat hanger die. Our results showed that rectangular cross-section feedblock generated higher values for pressure in comparison with the pressure generated by the circular cross-section feedblock. The maximum velocity generated in the circular feedblock is lower than that generated in the rectangular one, nevertheless there is more uniformity in velocity distribution in circular than rectangular cross-section.

This paper is to study weldability and joining characteristics of dissimilar metal welding between low carbon steel and ferritic stainless steel using ER308L and ER309L filler wires. Weldability and welded joints were evaluated by microstructure analysis and bend test. It was observed that the microstructure of the fusion zone and the bend test of the welded joint were significantly affected by welding parameters and filler wire. A welded joint prepared with high heat input using the ER309L filler wire exhibited a significant delta ferrite and austenite microstructure. In contrast, when employing the ER308L filler wire with a high intensity welding current, martensite, and carbide formed at the fusion zone. The bend property was acceptable for all the specimens, and there was no evidence of solidification cracking.

A process when different materials are combined to produce a product with multiple layers is called co-extrusion. During this process, polymers are melted in separate machines and then extrudate from different die channels. Once these channels converge, the polymers meet and flow through a single channel. The surface where the two fluids face is called “interface”. It is crucial to maintain the interface's uniformity and stability in order to achieve the desired multi-layered structure. Most of the issues in co-extrusion are related to issues that can be classified into two categories such as polymer encapsulation/interfacial distortion and die swell. To solve these problems, designers focus on improving the interface's stability. This paper examines effects of cross-section modification of the two-channel feedblock on the interface location and velocity and pressure distributions of the flow. The ANSYS software was used to simulate the co-extrusion of polymers, LLDPE and HDPE, in two-channel feedblock with rectangular, circular, and straight slot cross-sections. The results show that sharp corners increase the thickness of dead zones, while rounding them decreases the thickness. Additionally, stadium-shaped (or straight-slot) cross-section channels can move the flow with a higher maximum velocity and thinner boundary layer combining the results of rectangular and circular feedblocks.

Biological pollution creates significant obstacles in the operation of power plants' technical water supply cooling systems (SCS). To minimize biological pollution, methods of corrective treatment with biocides are implemented. While these biocides effectively prevent fouling of the cooling system, they can also adversely affect the environment and structural materials. By evaluating structural materials' corrosion resistance and biocides' environmental safety for the cooling water during biocide treatment, any potential issues can be identified and addressed before they become a safety or operational concern. The paper presents the results of bench tests of the corrosion resistance of structural materials SCS, corrosion aggressiveness of the biocides: sodium hypochlorite NaClO and 2, 2-dibromo-3-nitriloropionamide (DBNPA), and the results of measurements of the concentration of biocides and their decomposition products to assess compliance with environmental standards when discharging return water when applying from biocides treatment. The cooling water SCS of the Rivne NPP (Nuclear Power Plant) was chosen as the research object. Bench corrosion tests were carried out using samples of corrosion indicators from materials: steels Ст20, 08Х18Н10Т; copper alloy МНЖ-5-1 and aluminum, which are defined as analogs of structural materials of the technical water supply system of the Rivne NPP. The conditions of operation of the technical water SCS of the Rivne NPP were simulated on the test bench, and corrosion rate measurement was carried out by the gravimetric method.

This research paper aims to investigate the significance of considering the humidity factor during material selection in plastic product design. Humidity is a crucial environmental parameter that can profoundly influence the properties and performance of plastic materials. To ensure the long-term performance and dependability of plastic products, it is essential to comprehend and take into consideration the impacts of moisture on plastics. Humidity plays a fundamental role in the degradation and functional changes of plastic materials. Moisture absorption can lead to reduced mechanical strength and accelerated degradation processes. The selection of appropriate materials that can withstand humid conditions becomes paramount in product design. For this reason it is important to evaluate the moisture absorption properties of plastic materials. Different polymers exhibit varying degrees of moisture diffusion rates that directly affect their performance in humid environments. Evaluation of moisture measurement results allows designers to make informed decisions during material selection. For this reason, we designed an experiment to investigate which material retains less moisture. In our research, we determined 2 different experimental groups. The first of these groups (type A) was kept under normal conditions by adding glass fiber additive at different rates to the PA66 material, and each product with 3 different additives was tested for moisture for 10 days and the results were recorded. In the second experimental group, type B, the products produced with the same material and additives at the same rate were kept in water for 24 hours, then they were removed from the water and moisture tests were performed. It is aimed to make material selection by interpreting the test results and thus to facilitate the making of designs suitable for use.

The promise of transforming wastes from the Azores into building materials is the focus of this research. The insulation properties of some of these materials can be advantageous to the building construction sector. These materials are upcycled into non-structural components of the building such as panels for ceilings and walls as a factor to control thermal comfort economically. In this paper, insulation panels using cryptomeria waste from the carpentry industry were developed and experimentally evaluated in terms of conductivity for further study of their thermal properties, as well as life cycle analysis. Sodium silicate was used as a primary binding material along with these treated materials. The different composite panels made from the waste and surplus materials are expected to be analysed in Test cells that are built in Azores using this together with other wastes available in the region. These panels will be tested for longer periods in these test cells subjected to the local climatic conditions. The results of thermal conductivity are promising for the two composites sampled.

Sustainability is very important to keep industrial growth and human development going. Concrete is the largest manufacturing material in the world and includes cement as a key bonding agent for developing strength. This paper shows that the use of chopped carbon fiber to reinforce cementitious materials improved the mechanical properties characteristics of the mortar. also proposes appropriate curing conditions for the chosen mortar. The experimental investigation was carried out to evaluate the mechanical properties of cement mortar, The study plan consists of four cement mortar mixtures with ratios include 0%, 0.25%, 0.5% and 1% of chopped carbon fiber volume fraction by weight % of cement using normal water for curing. The effects of four different methods of curing on the mechanical properties of cement mortar that have the best properties from adding chopped carbon fiber were investigated including the convectional curing. 1% carbon fibers showed the best improvement in the mortar strength.

In this paper, a novel artificial staggered grid points and under-relaxation free solution for a checkerboard pattern problem in a quasi-one-dimensional, incompressible, steady, and inviscid flow is introduced. The purpose of this numerical development is to obtain a new numerical solution, which is under-relaxation factor free scheme, more accurate, and easier to implement than a conventional staggered grid scheme. The proposed numerical solution can be described as the non-staggered grid/collocated grid central difference scheme which is free of pressure checkerboard pattern or spurious oscillation. The accuracy and convergence speed of the proposed numerical scheme is benchmarked against a conventional SIMPLE-based finite volume scheme and the exact solution for the flow problem in a convergent nozzle. The numerical analysis shows that the proposed numerical scheme outperforms the SIMPLE-based finite volume scheme in terms of accuracy, computational resource, and convergence speed. Also, the proposed numerical scheme has consistent numbers of iteration over the different grid sizes in contrast to the SIMPLE-based scheme which is iteration-grid size dependent. The proposed numerical scheme can be implemented with both uniform and non-uniform grid points and shows good agreement with the exact solution for every grid size. However, the uniform grid approach produces significantly more accurate results than the non-uniform grid approach. Hence, the choice of grid distribution is still an important factor affecting the accuracy of the proposed numerical solution. The proposed numerical technique can be further extended to solve incompressible flow problem in the complex 2D-3D domain with unstructural grids.

The requirement for effective cooling of modern electrical and mechanical components has increased due to the desire for more compact and efficient designs. Thermal systems have used working fluids as a method for cooling systems for many years. However, technological improvements have dictated that working fluids must be more efficient for their applications. Researchers presented nanofluids as a possible solution for this issue, and they have gained a lot of attention due to their capability to enhance the heat transfer coefficient in miniaturized cooling or heating systems. The main purpose of this paper is to enhance the heat transfer coefficient in micro scales by encouraging the random motion of the particles in the nanofluid. This is accomplished by placing a nozzle between two micro-channels. The random motion of the particles is enhanced within the nozzle, increasing the heat transfer coefficient in the microchannel downstream as a result. In addition, the effects of characteristics of nanofluid are discussed briefly.