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The paper presents the results of experimental research on the development of a repair technique for a pipeline transporting hydrogen mixed with petroleum vapors, which has been in operation for 25 years at Mozyr Oil Refinery, the largest oil enterprise of the Republic of Belarus. The failure of this pipeline was caused by a crack formed in the weld root and its propagation along the fusion line of the heterogeneous weld joint. The developed technique made it possible to prevent further crack propagation without interrupting the refinery fractionation column operation. Welding of the main weld should be performed on a previously deposited damping layer. The damping layer must be deposited by using welding materials, the welding method and the technique that lead to creating a nonoriented dendritic structure. For this purpose, a welding material that has an energy of crack initiation and propagation greater than the energy of crack propagation in the base metal must be used. The composition of the weld must include chemical elements that inhibit the intensity of diffusion processes and increase the strength of the interatomic forces of the austenitic matrix at the pipeline operating temperature.

The paper presents a developed a technology for producing a new abrasive material, which is a refractory ceramic matrix made of aluminum oxide with embedded diamond particles. The tests have shown its advantage over traditional diamond-bearing materials when processing high-hardness ceramics. To synthesize a new material with a predetermined set of operational parameters, it is necessary to build a wear model of a friction pair composed of diamond-bearing ceramic material and ceramics. After analyzing the results of other authors’ studies and assessing the morphology of the contacting surfaces, it is assumed that the contact of microroughnesses on the friction surfaces of abrasive diamond-bearing ceramic tools is linearly elastic. The model is built within the framework of the basic wear equation. The composite material surface was modeled by a set of same radius spherical segments; diamond grains were distributed in the material with a given bulk density. The paper uses the concept of an equivalent surface with the power law distributed of microroughnesses tops. A theoretical relationship is obtained between the micro-and macrocharacteristics of the wear process of a composite ceramic friction pair. The authors established theoretically and confirmed experimentally that the grinding productivity increases with an increase in sliding speed, applied load and diamond grain size. The diamond concentration has no significant effect on the workpiece wear. The established dependencies can help to achieve high productivity of diamond ceramic tools.

The paper discusses computer modeling of the temperature dependences of the dielectric constant of polymer composite materials. Issues of the combined radio wave and thermal methods of diagnostics of nondestructive inspection of the polymer composite materials in the laboratory conditions are considered. The paper offers a method for combining the measurement and heating processes. This method can be implemented, the way is to do the heating and the measurement at the same frequency with using a high-power sounding wave. As a result, the radiant material heating is obtained, and we judge about the substance parameters and a presence of defects in the substance by a reflected wave in an indirect method. A descriptive characteristic of such a problem boils down to describing all the processes in the sample by the electrodynamic theory. The heating process can also be described by the electrodynamics equations, but the process will be described by the thermal equations in the nonstationary heating conditions in the most accurate way.

Based on the flow equation of the ferromagnetic liquid lubricant for the “thin layer”, the continuity equation and the Darcy equation describing the flow of a lubricant in a porous body, the paper presents an accurate self-similar solution of the V-shaped sliding support with a porous coating of the base ring surface taking into account the rheological properties of the lubricant with ferromagnetic properties when the working gap is partially filled at the laminar flow mode. Analytical dependencies were obtained for the field of velocities and pressures in lubricating and porous layers. Besides, the main working characteristics of the studied friction pair are determined: bearing capacity and friction force. The paper provides the assessment of the influence of parameters characterizing ferromagnetic rheological properties, length of the loaded region of the Hartmann number and parameter characterizing the presence of electromagnetic field on the bearing capacity and friction force.

Extraction of thorium oxide (ThO2) from monazite mineral specifically from Perak, Malaysia become a bright opportunity for the new income generation in Malaysia eventhough it is involved complex processing routes and require variety of chemicals. Monazite that is known as monazite-(Ce)-PO4 minerals, not just contain thorium, but it also consist rare earth elements (REE) such as cerium (Ce), neodymium (Nd), lanthanum (La) and gadolinium (Gd) and also associated with thorium (Th) and uranium (U) at about 7 wt% and 0.2 wt% respectively. One of the challenges in this R&D work is to determine the presence of thorium, uranium and REE at each processing step due to its similarities of chemical composition and physical properties. Therefore, the aim of this paper is to use several x-ray characterization techniques to identify elemental composition obtained at each processing route to show the evidence of the presence of ThO2 extracted from Malaysia monazite. This paper focused on the use of wavelength dispersive x-ray fluorescence (WDXRF), field emission scanning electron microscope (FESEM) with energy dispersive x-ray (EDX) and x-ray diffraction (XRD) spectrometer to show evidence of ThO2 formation. Result shows that the final product contain of 85 wt% of ThO2 and it is thorianite with nanorod morphology. Thus, conforming that the feasibility of the current processing route to produce ThO2 from Malaysia monazite.

Aiming at the reliability of thin-film thermocouples applied to turbine blades at high temperatures, combined with high-temperature tests and finite element analysis, this paper studies its failure mechanism and thermal stress under thermal load. Multi-layer thin-film thermocouple samples were prepared on ceramic substrate, and high-temperature tests were carried out under different temperature loads, and the phenomenon of film shedding and cracking was observed using electron microscope. This paper analyzes the failure mechanism of the film sensor based on the function and structure, and uses ANSYS to analyze the thermal stress distribution of the film under high temperature load. Combining several existing theoretical models, this paper analyzes the factors affecting the thermal stress of the film and conducts simulation verification.

The paper presents a study on the performance of cutter tip for wood milling process. The tests were performed with the tropical wood samples which were milled in the double sided wood planer, the measured micro-geometrical parameters encompassing the linear wear and tooltip radius. The study primarily contributes to developing a far better understanding of the physical nature of cutting tool wear in response with the growing concern of many researchers. Given this basis, it does not only assist the selection of reasonable cutting tool but also enable the detection of the patterns in the cutting tool wear process. In terms of tool wear and bluntness, there has been a number of researches taking account into the physical nature of cutting tools, - providing basis for selection of cutting tools apart from clarification of the current pattern of tool wear and bluntness. The load applied to the cutter during wood milling is the load that changes marks periodically. When starting to work after tool sharpening and finishing, the first stage changes the microscopic geometry - tool run-in process (rapid initial wear), followed by constant conditions of wear before a rapid wear which leads to failure at last. The objective of this study is to determine the influence of the cutting path to the tooltip radius and linear wear of the cutting edge. The paper employs method of least squares and variance analysis in application of the Minitab software to determine regression equations for relation of the tooltip radius and linear wear to the relative cutting length. The ultimate goal is to predict the life of cutting tool when milling tropical wood.

AlSn20Cu alloy is currently one of the most widely used bearing materials, and its microstructure is the most important indicator in application. In this paper, AlSn20Cu alloy ingots were prepared by two methods: ordinary casting and semi-continuous casting, and deformation and annealing process of the two ingots were studied. Scanning electron microscope (SEM) and Image Pro Plus software were used to observe and analyze the evolution of the microstructure, and the morphological information such as the average grain size and area fraction of the Sn phase was quantitatively characterized. The effects of casting method, deformation temperature, deformation amount and annealing temperature on the morphology of Sn phase were studied in this paper. Compared with ordinary casting, the cooling rate of semi-continuous casting is higher, so the Sn phase is smaller, the casting defects are less, and the deformability of the alloy is better. The AlSn20Cu alloy prepared by ordinary casting has better deformability at about 140 °C, while the AlSn20Cu alloy prepared by semi-continuous casting can be rolled and deformed at room temperature. When the deformation is greater than 40%, after annealing at 250 °C, the average grain size of the Sn phase in the AlSn20Cu alloy prepared by semi-continuous casting is around one hundred square microns and the area fraction is more than 10%, and the Sn phase morphology is better than ordinary casting alloy under any processing conditions.

China's coal resources are extremely rich, and the degree of coal mining is high. During the formation of coal, a large amount of coal gangue will be produced, which not only accumulates land and wastes resources, but may also cause natural disasters such as fires. In this paper, coal gangue is used as the main raw material, and a certain amount of kaolin, steel slag and other auxiliary materials are added to prepare coal gangue ceramsite through a high-temperature sintering process. The research results show that as the sintering temperature increases, the porosity of the ceramsite decreases first. After increasing, the water absorption rate of ceramsite also decreases first and then increases with the increase of the firing temperature, while the compressive strength first decreases and then increases with the increase of temperature. With the increase of the holding time, the porosity of the ceramsite first decreases and then increases. The water absorption rate of the ceramsite also first decreases and then increases with the increase of the firing temperature, while the compressive strength decreases first and then increases with the increase of the temperature. Elevated. With the increase of coal gangue content, the porosity of ceramsite gradually decreases, the water absorption rate of ceramsite also gradually decreases, and the compressive strength gradually increases with the increase of coal gangue content. The optimization can be obtained, the coal gangue content (mass fraction) is 100%, the calcination process system is 1200°C, and the heat preservation time is 60min as the better parameters. At this time, the compressive strength is 29.57MPa and the porosity is 4.36%.

Deep drawing has become the most general method in cartridge manufacturing process which use brass alloy as the main component. To perform deep drawing on this type of alloy, there are several physical and mechanical properties re-quired, especially the ductility and hardness. In this paper, the CuZn35 brass alloy, which still does not fulfill the requirements, had been annealed in the several annealing parameters (holding time and annealing temperature) to achieve the re-quired properties. It also discussed the microstructure evolution in every annealing parameter and the affiliation to its mechanical properties. The temperature annealing process of CuZn35 brass alloy was conducted in 300, 400, 500, and 600°C for 60 minutes. Then, the heat-treated product will be observed to get the composition, microstructure, hardness, strength, and also deep drawing formability. The-ꞵ precipitation was successfully eliminated by annealing process which significantly decrease its hardness and tensile strength whereas the increased grain size affect the ductility.

In this paper, the diameter of 1.2mm and 1.6mm welding wires were used to carry out high-frequency pulse MAG butt welding process test on S355J2W+N weathering steel. The analysis of the microstructure characteristics of the welded joints under the two working conditions shows that there is little difference and both are ideal. There were more acculate ferrite (AF), less pearlite (P) and bainite (BG), and no larger Weisserite structure and less ferrite side-plate (FSP) structure. The weld is well formed, weld defects such as gas pores and cracks are not found. The impact test showed that the impact energy Akv (-40 °C) of the welded joint at -40 °C was higher than the specified minimum impact energy of 27 J. Compared with the 1.2mm welding wire, the impact energy of the 1.6mm welding wire is lower. Tensile test results show that the fracture occurs at the base metal position. and the fracture height is uneven, forming an angle of 45° with the tensile stress direction, which is a ductile fracture. When the bending angle of the butt joint samples reaches 180°, no cracks are both found on the tensile surface, and the plastic index of the welded joint samples is qualified and has good bending performance.

The straightness movement error of the machine tools axis contributes significantly to the straightness of the workpiece machining feature. This paper focuses on the assessment study of CNC machine tools’ straightness geometric error for obtaining recommendation information to improve machine geometric accuracy. A research method by determining measurement parameters according to ISO 230 procedure, no-load measurement of straightness vertical-horizontal geometric error using a laser interferometer, collecting data, data analysis. Data analysis calculates positional straightness deviation, mean positional deviation, systematic positional deviation, repeatability, and accuracy of straightness movement for each machine axis, and generating error compensation values for improving machine geometric error. The travelled distance of the X, Y, and Z-axis CNC milling machine tested is about 1100 mm, 560 mm, and 520 mm. The assessment result shows mean deviation straightness horizontal of X, Y, and Z-axis is 4.14 μm, 3.41μm, and 0.95 μm. The mean deviation straightness vertical of X, Y, and Z-axis is 3.75 μm, 2.63 μm, and 2.30 μm. Finally, the assessment outcome is generating error compensation values of each axis. It could be recommendation information for setting back error compensation parameter on CNC controller, hence the mean deviation of straightness geometric error machine tools to be less than 1 μm.

Pipelines are a common medium to transfer hydrocarbons, but their integrity is compromised by corrosion issues specifically in top of line corrosion (TLC) due to several influence factors such as water condensation. Water condensation occurs due to a significant variance in temperature outside the pipeline and inside the pipeline as water condenses in the inner pipeline. Hence, this paper aims to study the water condensation rate (WCR) behaviour in the presence of gas condensate in wet gas pipelines. The objectives of the research are to determine the components of the gas condensate by characterizing the gas condensate using Gas Chromatography-Mass Spectrometry (GC-MS) and Fourier-Transform Infrared Spectroscopy (FTIR) equipment and later to determine the effect of gas condensate on water condensation rate by conducting 2 different experiments. The condition of TLC was imitated by using a customized TLC testing unit, whereby 2 sets of API 5L X65 carbon steel coupons were used. Meanwhile, the delta temperature of the gas and steel obtained by regulating the temperature setting of the chiller and hot plate respectively enabled the water condensation process to be simulated. Throughout the 7-days of experiments, the gas and steel temperature were daily monitored and the water that only condensed on the surface of the coupons was collected and measured. Subsequently, the WCR was determined. The first objective was achieved as the result from GC-MS showed that there were 67 compounds in the condensate, and 5 functional groups were detected using FTIR, which confirmed that the gas condensate used in this experiment was similar to the gas condensate obtained from the pipelines. The second objective proved that condensate affected the water condensation rate, in which the WCR was reduced by about 73% with the presence of condensate. This WCR reduction is postulated because of the two different liquids (water and hydrocarbon) competing for the same surface area (top metal coupon) to condense.

In Malaysia, food waste had become a significant problem. These recyclable natural waste resources are channeled towards the production of value-added products e.g. hydroxyapatite; which can be used as photo catalyst and many other applications. This study synthesized hydroxyapatite (HAP; Ca10(PO4)6(OH)2) powder from food waste using wet precipitation method. FTIR analysis was done on the synthesized hydroxyapatite powder, calcined samples and raw materials for each resource to study the functional group and the changes of composition in each sample. The Life Cycle Analysis (LCA) study done in this paper comprises of goal and scope definition, life cycle inventory, life cycle impact assessment as well as interpretation of data. Based on the results obtained, FTIR analysis shows that the synthesized powder is indeed hydroxyapatite based on the presence of important feature such as CO32- and PO43- and OH group and egg shell is proven to be the eco-friendliest resource as the production process contributed only 1% to environmental impact.

Chemical manufacture is a significant value-added industry in both local and global economies. Along with highly relevant issues such as unsustainable process design, energy consumption, and waste generation linked with the sector, societal issues relating to chemical product health and safety are part of the greater sustainability concerns. There is a need to design a sustainable strategy while ensuring economic stability at the corporate level. Hence, this paper presents a methodological proposal of integrated modelling approach for sustainable chemical process design at early design process. The step of achieving this objective is separated into several parts. The first step is to classify parameters from established tools as a benchmark for sustainability metrics. The next step is to transform quantification value of triple bottom line impact (economic, environment and social) to normalized weightage by using Multi Criteria Analysis. The final stage is to develop alternative in terms of technical optimization of process design. The implementation multimodal Multi Criteria Analysis and optimized process design exhibits significant improvements in sustainability impacts according to the waste reduction (WAR) algorithm.

In this paper, BaO-ZnO-TiO2-SiO2 is used as the research system of high refractive index glass, and IR, XRD and DTA are used to study the structure, thermal behavior, crystallization and chemical stability of different glasses when B2O3 gradually replaces SiO2. The results show that when B2O3 replaces SiO2, glass still has an amorphous structure, and the density of glass shows a decreasing trend with the increase of B2O3 content. With the increase of B2O3 content, the boron-oxygen tetrahedron gradually transforms into the boron-oxygen triangle, which makes the overall crystallization of the glass structure weaken. The results show that the density, refractive index and water resistance of glass beads without B2O3 are the best. With the increase of B2O3 content, the activation energy of crystallization decreases, the potential barrier to be overcome for crystallization decreases, as the same time the phenomenon of glass crystallization is obvious. Keywords:High refractive index glass; BaO-ZnO-TiO2-SiO2; Crystallization; Chemical stability

Preparation of boride by chemical vapor deposition (CVD) is sensitive to oxygen, subtle changes in oxygen concentration during the deposition of ZrB2 can induce the formation of Zirconium dioxide (ZrO2) with a novel nanoplate-stacked structure and nanowire structure. The ZrO2 nanostructure changed with - oxygen concentration. Nanowires with uniform size of 50-100 nm in diameter and over 100 μm in length were obtained at high oxygen concentration, while highly-ordered nanoplate arrays were obtained at low oxygen concentration. Both of these nanostructures were grown in situ on the surface of ZrB2-coating. In this paper, the preparation method of novelty ZrO2 nano-structures grown in situ was provided, the morphologies and compositions of the nano-structural ZrO2 were characterized and the formation mechanism was proposed, which also provides experimental basis for the industrial morphology control of ZrB2 deposited by CVD method.

This study focused on the production of bioactive pure cordierite ceramic and the evaluation of its bioactivity by immersing it in simulated bodily fluid (SBF) and coating it on CP-Ti utilizing the dip coating Procedure. Cordierite is created by chemical coprecipitation, which involves combining Cordierite gel with a water-based sol-gel composed of Alumina Al2O3, magnesium oxide MgO, and silicon oxide SiO2. They used a hydraulic press to form cordierite into a cylindrical shape with a pressure of 4 bar and a holding time of 30 minutes at this pressure. Firing presses reach temperatures of 1250 Co and have a holding time of 2 hours. A Field Emission Scanning Electron Microscope (FESEM) was used to examine the microstructure, which revealed a homogenous distribution of the compounds with negligible porosities. The phase transitions that cur during the sintering Process is studied using X-ray diffraction (XRD). The structural investigation of specimens revealed the formation of the cordierite phase at 1250 Co, as well as the development of cristobalite, spinel, protoestatite, and corundum with cordierite phase. The dip coating Procedure was utilized to cover commercial pure titanium (CP-Ti) samples with cordierite powder. CP and Tafel exploration tests show that coated CP-Ti has superior passivation than uncoated Substrate. By comparing the findings of uncoated and coated CP-Ti, this paper concludes that the cordierite system acts as a good passivation layer.

Titanium and its alloys are attractive engineering materials used in aerospace, automotive, biomedical, and marine industry because of their outstanding mechanical properties such as high specific strength and physical properties with excellent corrosion resistance and excellent elevated temperature properties. This paper presents a brief review on the The effects of ball-milling time on the microstructure and mechanical properties of the ball-milled powder and sintered compact were investigated. As-milled powders and sintered Ti-Alloys samples were evaluated by X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry, laser diffraction particle size analysis, and transmission electron microscopy.

The Magnesium and its alloys are majorly utilized in automotive, aerospace, and biomedical applications because of their extensive properties. The approach for the preparation of the Magnesium materials is done by modern powder metallurgy. This method allows us to study the structural, mechanical, and controlled corrosion resistance. In the present paper, the effect of cold compaction on magnesium AZ31B alloy are studied, were Ultra-Fined Grained (UFG) Magnesium AZ31B alloys of particle size 60 nm were obtained by 8hrs of Ball milling followed by cold compaction at the pressure of 40Mpa at laboratory temperatures. Sintering process for 8hrs were done for cold compacted specimens at temperatures of 425°C,450°C and 475°C in a Horizontal tubular vacuum furnace. Influence of compacting pressure and sintering were investigated for properties of microstructural, mechanical and corrosion resistance. It was observed that, during cold compaction process for Magnesium AZ31B alloys the product grains are distributed uniformly with less pores and particle boundaries. Homogenization were attended by sintering process and Microstructural, Mechanical properties strength, were shown extensive results of hardness and compressive strength of 516Mpa and 123Mpa, as the sintering temperatures were increased from 425°C to 475°C. The lowest corrosion resistance of 0.35 mm.y-1 is obtained for compacted AZ31B alloy as the temperature of sintering temperature raised to 475°C.

The rapid advancement in the extraction method of metallic oxide nanoparticles from agricultural waste has led to the significant use of agriculture waste in the nanotechnology industry because the use of chemical procedures in the production of metallic oxide nanoparticles produces hazardous toxic compounds that are dangerous to the ecosystem. In particular, this article examines the creation of silicon dioxide (silica) nanoparticles from agricultural waste. Environmental cleanup and wastewater purification are only two examples of the many areas where sand-sized silica particles (SNPs) have shown promising results. rural, agricultural, etc. The lack of toxicity of these particles has been demonstrated, making them an excellent tool for biomedical study. Additionally, because of the particles' ability to mobilize molecules onto their interior and external surfaces, they constitute good transporters for both biotic and non-biotic substances. In this regard, the current paper provides a thorough assessment of the sources of agricultural waste used in producing silica nanoparticles as well as the processes used to create it. The report also examines SNPs' most recent applications in a number of fields and discusses the technology's potential for the future. Keywords: Fuel additives; ethanol; brake power; Internal combustion engine; fuel

This paper deals with the problematics of utilization of waste perlite from production of expanded perlite in polymer-based material. The goal of this paper is to develop repair mortar containing as high amount of waste perlite as possible as substitution for filler. The resulting mortar exhibits very high physical-mechanical properties such as high bonding strength to a large variety of building materials. The microstructure and the re-dispersibility of filler were also studied.

The objective of this paper is to calculate the influential properties of concrete. These are the dynamic properties of sustainable concrete in the situation in which metal waste can found within its components. Growing the rate of pollution in the world, a fast decrease of the original resource, the requirement for utilization more areas of natural land, and increase the price of the newly available area are the reasons that make the researchers give great attention to the new concrete (green concrete) and destruction of unwanted material in the green mix. The concept of reuse aimed at sustainable structures was implemented within the current paper through consuming metal waste of cans and bottle caps in concrete. The waste materials were consumed in two modes; at 1st mode, it was applied in the role of fibres and mixed using 15% by weight of cement. On the 2nd mode, it was applied as coarse aggregate with 25% replaced by volume. The procedure includes testing 4 concrete mixes. The estimated properties were the flexural and compressive strengths, besides modulus of elasticity. Adding bottle caps (waste materials fibres) in concrete led to enhancement in strengths. The use of walls of cans (waste materials fibres) in concrete reduced the strengths. While in the case of compacted bottle caps plus pull-tab of cans (waste materials aggregate), concrete mechanical properties a little below the reference mix. The dynamic properties of concrete contain these types of waste under impact load were determined. As known, the dynamic properties are so helpful in the strategy that deals with civil constructions put in danger of impact loads like runways, gas explosion, etc. CEB-FIP (2010) code provides wide-ranging formulas to predict the strain change of concrete. The dynamic properties are determined by this code with consideration strain level between (10-2-100). In this range, dynamic loads in the civil constructions at the level of quasi-static strain were predicted.

This paper conducts surveys on the design, construction and use of the ICF system, a new type of low-energy and industrialized house that has emerged in Guanzhong rural area of China in recent years. The survey content includes family background, house layout design, construction and cost, details and energy consumption simulation, temperature test etc. The paper summarizes the reasons for the popularity of the ICF system and the issues that need attention in future promotions. Construction optimization is also proposed for thermal bridge at the window opening, so that this new system can exert a more comprehensive energy-saving performance.

The scientific paper presents an extensive research on modeling and optimizing the technological parameters of the process for processing by processing electric discharges with massive electrode with and without magnetic activation. Scientific research is based on real data collected from the process of electrical discharges performed on various samples extracted from areas of welded joints of metal components made of high alloy steel. The processing of experimental data was performed both classically and actively, especially the method of the central factorial experiment composed of orthogonal and rotary. The process parameters that were initially modeled and subsequently optimized were based on a series of independent variables characteristic of dimensional processing by copying the shape of the electrical discharge processing. Subsequent research conclusions and directions, as well as original contributions, are an experimentally validated point of view and worthy of consideration. All these fundamental ideas highlighted above find their explanations and the corresponding explicit treatment in the content of this scientific paper that addresses both managers at all levels and researchers.

During the last 15 years, the friction stir welding process (FSW) and the techniques developed based on the FSW principle have been a main research direction within ISIM Timisoara. The paper summarizes activities and results obtained by the FSW research team within the institute. The paper presents a synthesis that aims a briefly presentation of its own achievements and contributions from recent years regarding the development of the FSW process, especially on the following directions:- Friction stir welding on couples of similar and dissimilar materials;- Use of FSW-TIG (friction stir welding – tungsten inert gas assisted) and FSW-US hybrid processes friction stir welding - ultrasonic assisted);- Friction stir welding in protective gas environment;- Friction stir welding equipment and tools;- Systems for monitoring of the welding process. Results obtained at friction stir butt welding or by overlapping of some couples of materials that are difficult or impossible to be joined using conventional welding procedures, were presented. The results obtained during these years, as well as their scientific and technical level, have allowed the proposal for implementation of solutions that involve FSW welding for specific industrial applications (especially for the automotive field).

Considering the remarkable results obtained by using friction stir welding process (FSW), ISIM Timisoara has developed research programs for the knowledge and development of processing processes based on the FSW process principle.The paper presents a synthesis of the researches and the results obtained within some of research projects carried out by ISIM Timisoara, regarding possibilities of using some of processes derived from the FSW process, which has focused mainly on two directions (areas): surface engineering (materials surface processing) and joining by friction riveting. In the field of surfaces engineering, there are presented some results that represent own contributions of ISIM Timisoara, regarding: friction stir processing as well as coating with functional layers from lightweight alloys of steel substrates (by friction with consumable tool).Regarding friction riveting, two methods are presented: classic friction riveting, respectively friction riveting with hybrid effect (mechanical grip and friction welding).The paper shows very good results obtained to FSP processing (for cast aluminum alloys), to friction riveting with hybrid effect (for aluminum and copper alloys) and to friction riveting (for aluminum alloy), but also some limitations of these friction processing methods.Also in the paper are presented new research directions that are currently being addressed, respectively that will be addressed in the next period at ISIM Timisoara, regarding new variants of application of FSW welding.

Throughout the history of modernization of welding processes, in many cases the research has focused on optimizing the location of energy in the welding area, with the continuous improvement of the quality of welded joints. The welding processes in shielding gas environment with fusible electrode (MIG-MAG) have achieved superior performances regarding the increase of the current density around of the welded joint, simultaneously with the increase of the universality degree of their application. This paper is based on researching the possibilities of concentrating energy in the welding area, seeking to obtain both more favorable energy yields and an increased quality of welded joints. In the paper are shown a some results obtained following a comparative study on 2 welding processes in MIG-MAG protective gas medium, differentiated mainly by the metal drop transfer mode: by spraying (Spray arc), respectively by synergistic transfer (Arc pulsed), applied for corner welding of alloy steel sheets.

The paper deals with the experimental and theoretical results of elastic constants of polymer modified high strength concrete with high fibre volume fraction. To evaluate elastic properties of this composite system, compressive and flexural strengths were obtained experimentally. Elastic properties such as modulus of elasticity and Poisson’s ratio are first obtained based on experimental results. Simplified equations based on micromechanics, and solid mechanics theories are utilized for the evaluation of elastic properties of polymer modified randomly oriented short steel fibre reinforced high strength concrete. The micromechanics equations for the modulus of elasticity and the Poisson’s ratio are based on the fibre volume fraction and the elastic moduli of the fibre and polymer modified concrete matrix. The existing empirical equations are also used to obtain elastic constants. These equations are applied in the full range of fiber volume fraction (1% to 10%). The comparison of experimental results with theoretical values shows the good agreement with each other. The novelty of the present paper is that the modulus of elasticity of this composite system is obtained experimentally using four point bending test and the Poisson’s ratio is obtained as a function of flexural and compressive strengths with excellent accuracy for the first time.

This paper dwells upon finding the specific surface area of cake, a coal enrichment waste, exposed to electroplasma treatment; the goal is to make an organomineral porous material to be used as a sorbent for wastewater treatment. The research team used a monomolecular Langmuir adsorption model and surface tension of the surfactants before and after adsorption at the interface of solution and solid adsorbent. Another process considered herein was thermal activation of substances in the electroplasmic reactor for making organomineral porous materials from coal cakes. The paper presents the resulting specific surfaces area of the organomineral sorbent thus produced. Thus, the waste of flotation, i.e. coal cake, is fundamentally suitable for making porous substances by thermal destruction in an electroplasma reactor.

The paper presents the results of experimental studies on the determination of corrosion products on the surface of reinforced concrete structures. This paper also discusses methods for creating samples with artificial electro corrosion under conditions close to real operation. The paper presents the results of testing samples using laser-inducted breakdown spectrometry (LIBS) devices.

In Lebanon, the demand for energy is constantly increasing. A tremendous increase of 83% in energy demand was recorded between 2009 and 2019. The national electricity company (EDL) is unable to supply electricity needs. These needs are covered by expansive and polluting backup generators. Furthermore, according to the World Bank (2016), the national power sector share was 57.8% of total CO2 emissions in 2015, and 25.2% among them came from private diesel generators. The building sector and related activities is responsible of a large part of energy consumption. Thus, phase change materials with different ways of building integration are used as a solution. In this paper, a representation of different types and building integration methods of PCM is conducted. This paper review will present the previous studies concerning different types and integration methods of PCM, furthermore, environmental, energetic, and economic viability study will be highlighted simultaneously tackling future challenges in regards to PCM integration into buildings under Lebanese climate conditions.

Concrete, which is reinforced by steel fibers, represents a multifunctional building material that is able to realize flexible but stable structures. As an alternative to the energy-intensive conventional production procedure wire drawing, a combination of a notch rolling and cyclic bending process is proposed by Stahl [1] to produce those fibers. Besides representing the properties of steel fibers and the overall process, the paper brings the layout of both process steps into focus. Since notch rolling for the production of wire strip is mainly unexplored, a general conceptual design of the process and the rolling tools is performed, supplemented by a similar study on the fulling process. To enable a further evaluation of the process chain and its relevant process parameters, a numerical and experimental test phase using strip of a dual phase steel DP600 with a sheet thickness of t0 = 0.8 mm is intended in future. For ensuring high-quality numerical model, relevant behavior of the test strip is characterized through appropriate experiments and according material models in the present paper.

Loading history makes fatigue crack propagation modelling complex. This article focus on life prediction models which take into consideration the variability of fluctuating loads. In particular it emphases on the comparative studies of prediction models involving the significance of one model’s over another. The paper studies models based on multifarious loadings (constant amplitude load, variable amplitude load, overload/underload etc.). The major parameters of load interaction modelling are plasticity, crack closure, effective stress intensity, effective stress ratio and damage accumulation. For large deformation, elasto-plastic fracture mechanics based models are also included. The complexity of models, their features and focusing on their limitation and strengths are stated with various conditions and also validation of models with experimental data are reported. The paper speculates on the directions the study of crack propagation will take in future.

Laser-based Direct Energy Deposition (L-DED) is a very quick and freeform fabrication process. L-DED is useful to fabricate near net shape for engineering applications as well as medical applications. L-DED has been successful in making a variety of pure metals and its alloys for industrial needs. This review paper gives an overview of the research progress in various types of metallic materials like nickel alloys, Stainless Steel (SS), and Functionally Graded Materials (FGMs) fabricated by L-DED. Simultaneously, the effects of process parametric related factors also discussed. Introduction about nickel alloys, Stainless Steel, and FGMs relevant findings, and their advantages and disadvantages for these alloys are communicated. The paper shows the metallurgical, mechanical properties, and post-processing effects on L-DED fabricated nickel alloys, SS, and FGMs. This paper will be helpful to the researchers and industrialists and for those who are interested to do research in this field.

The application of nanomaterials in oil and gas fields development has solved many problems and pushed forward the development of petroleum engineering technology. Nanomaterials have also been used in wellbore fluids. Nanomaterials with special properties can play an important role in improving the strength and flexibility of mud cake, reducing friction between the drill string and wellbore and maintaining wellbore stability. Adding nanomaterials into the cement slurry can eliminate gas channeling through excellent zonal isolation and improve the cementing strength of cement stone, thereby facilitating the protection and discovery of reservoirs and enhancing the oil and gas recovery. This paper tracks the application progress of nanomaterials in wellbore fluids in oil and gas fields in recent years, including drilling fluids, cement slurries. Through the tracking and analysis of this paper, it is concluded that the applications of nanomaterials in wellbore fluids in oil and gas fields show a huge potential and can improve the performance of wellbore fluids.

Building material innovations in various interlocking concrete block masonry from local materials to withstand lateral earthquake forces is an exciting issue in masonry wall research. The block hook has an advantage in the interlocking system's invention to withstand loads in the in-plane and out-of-plane orientations commonly required by the masonry walls against earthquake forces. Reviews of the investigation of in-plane and out-of-plane masonry walls have rarely been found in previous studies. In this paper, the results of a series of experimental tests with different interlocking models in resisting the simultaneous in-plane shear and out-of-plane bending actions on concrete blocks are presented. This paper presents a research investigation of various interlocking concrete blocks' mechanical properties with different hook thicknesses. Discussion of the trends mentioned above and their implications towards interlocking concrete block mechanical properties is provided.

In this paper, a fluorescent probe based on a rhodamine spirolactam ring was designed and synthesized. Rhodamine derivatives not only have excellent chemical and optical-physical properties, but also the "OFF-ON" characteristic of the rhodamine spiroamide ring allows specific recognition and response to metal ions. In this paper, Rh-DCP, a rhodamine B derivative with a spirolactam ring, was synthesized by the Schiff base reaction and the effects of pH, time and temperature on this probe were tested.

There is a need to address the gap between the theoretical benefits and cost-efficient production of supercapacitors in the market in order to sway the preference of the industry from the current perishable energy sources and storage. More extensive exploration of sustainable fabrication methods and materials used for renewable energy storage are just some of the factors that would decrease this gap. A binder-free supercapacitor electrode made of NiCo2O4 and carbonized kapok fiber paper (CKFP) was successfully fabricated by hydrothermal process at relatively low temperatures. NiCo2O4 urchin-like structures were deposited on the surface of carbon fiber paper (CFP) and CKFP. XRD analysis confirmed the successful conversion of kapok fiber paper to CKFP after pyrolysis, as well as the growth of pure spinel NiCo2O4 nanostructures on CFP and CKFP. The cyclic voltammetry curves showed that the CFP-NiCo2O4 prepared at 140 °C had the highest specific capacitance of 143.51 Fg-1 at 2 mVs-1. The CKFP-NiCo2O4 synthesized at the same temperature yielded slightly higher specific capacitance of 146.29 Fg-1 at 2 mVs-1, and 508 Fg-1 at 0.5 Ag-1.

This paper presents the predicted results of nonlinear time history analysis of 11 storey (G+10) Reinforced Concrete (RC) residential building under the effects of a strong earthquake. The paper includes studying the effects of using Lead Rubber Bearings (LRB) as base isolators to improve the performance of RC building to sustain the impact of an earthquake. It also includes the effects of the infill panels on the overall dynamic response of both fixed base and base-isolated buildings subjected to a strong earthquake. The main results that are presented in this study include the variation of roof acceleration, roof displacement, base shear with time. The effects of using LRB and including the infill panels on the storey drift are also presented. Maximum reduction in the story drift was obtained when infill panels are included in the analysis of the base isolated building. The inclusion of the infill panels has only marginal effects on the variation of roof displacement with time when the building is isolated by LRB. The main important improvements that emerged from using LRB as well as the infill panels in the analysis are the reduction of inelastic energy and upgrading the elastic one that is summed up along the period of the earthquake.

Flexible pavement failure has been a major problem encountered in various countries. Some common distress which had been listed are cracking and rutting. The causes of this distress are due to moisture, weak sub-grades and poor construction quality. High amount of distress in the pavement however is likely to cause dis-comfort for the passengers, higher accident rate and heavy traffic. Study suggested that, flexible pavement failure can be reduce, through maintenance of the wearing course of the pavement, improving the base, sub-base layer or the sub-grade soil underneath of the pavement. However, high production or material cost, high construction cost, excessive settlement, or weak inter-molecular bonds in the flexible pavement are some of the common problem encountered with the current improvement techniques. This significance difference of this review paper compare to other is that, in this review paper it focuses on the flexible pavement failure, the different types of improvement method currently applied. Consequently, it further recommend flexible pavement improvement method through by reducing the sub-base layer thickness and inclusion of light weight material in the sub-base layer so that, the settlement of the pavement is reduced.

This paper presents the development of a binder from coal ash and rice husk ash for manufacturing hollow blocks. Experiments were conducted to determine the compressive strength of the coal ash and rice husk ash as binders using cylindrical specimens at different curing periods. The mixture proportion with the highest compressive strength in the experiment was adopted in making the 4” hollow blocks. The compressive strength of the hollow blocks with the coal ash and rice husk ash binder was also determined at different curing periods.Cylindrical specimens with four different alkali activators were made and subjected to compression testing on the 3rd, 5th, and 7th day of curing. The mean compressive strength of the cylindrical specimen with all sodium hydroxide activator (RS0CS0) after 7 days curing is 2.54 MPa as compared to 3.05 MPa with the 2.5 sodium silicate to sodium hydroxide ratio (RS1CS0). As the amount of sodium silicate from rice husk was doubled (RS2CS0), the average compressive strength of the 7 days old cylindrical samples increased from 3.05 MPa to 3.49 MPa. Meanwhile, the 7th-day compressive strength of the cylindrical specimen with commercial silica (RS0CS1) was 5.5 Mpa.Hollow blocks were also manufactured based on the material proportion that utilizes RHA with the highest compressive strength or the design mixture RS2CS0. These blocks have a mean compressive strength of 1.22 MPa on the 3rd day, 1.88 MPa on the 7th day, and 2.7 MPa on the 14th day of the curing period.

This paper presented an analysis of the two-step of hot forging process are carried out to manufacture Upper Ball joint, which are including roughing and finishing operation. The part was made from SNCM8 alloy steel. The simulation has been done with application of QForm V10.1.6 software. The constitutive model based on Zener-Hollomon parameter was applied. As a result of simulations, metal flow lines, plastic strain, temperature distribution and effective stress for forgings were obtained. Finite element simulation by QForm V10.1.6. software is suggested as a valuable tool for predicting the hot deformation behavior of material during multi-stage of hot forging process which utilized to enhance the manufacturing process. In addition, the forming load and thickness during the forging process were analyzed. It was found that the deviation of forming load between simulation and experiment was raised to 10.71% and the maximum error of flank thickness was 5.137%. within specification. Therefore, the workpieces of the quality required by specification are obtained.

In recent years, as global environmental problems have become more serious, the concept of sustainable development, such as the 3Rs, has become increasingly important. Against this backdrop, machinery and equipment are becoming smaller, lighter, and more sophisticated and multifunctional, and highly integrated products increasingly require the machining and assembly of minute mechanical parts. However, the fact that small machine tools generate relatively large amounts of servo standby power during operation calls for proposals for machining methods that reduce power consumption. In this paper, we have developed a novel 5-axes controlled machine tool equipped with an idling-stop function in a feed driving system to reduce the power consumption of machining processes. A problem has been emerged that start-up power increased as the velocity increased. In the present report, we therefore investigate the influence of various programing paths on the power consumption using an idling-stop function when the end milling process is operated in the X-Y plane. As a result, it can be seen that a suitable programing route is occurs for each feed velocity to reduce the power consumption with a developed machine tool.

In this paper, the influence of the surface roughness of build plates as well as the process parameters laser power, scan speed and exposure curing time on the bonding of additively manufactured components made of TiAl6V4 to the build plates is analyzed. These analyses are carried out with build plates made of Titanium Grade 2 and AlMgSi0.5. The analyses show that higher surface roughness leads to lower bending strength and thus poorer bonding of components on the build plate. In addition, it is shown that the bending strength normalized to the bonding surface decreases at high laser power, especially at high scanning speeds. Furthermore, multiple exposure results in lower flexural strength.

The application of laser-structured metal surfaces to combine plastics and metals is a promising option to enable low-cost lightweight and resource-efficient multi-material joints. The mechanical properties (especially strength), as well as production time and costs, depend on the microstructure of the metal surface (e.g. the number, distance and shape of cavities). Thus, in order to design optimal joints, the properties from the mechanical, as well as production and cost domain, must be considered simultaneously during product development. Therefore, in this paper, a model-based optimization approach is presented with the goal of identifying an optimum between the strength of the joint and laser manufacturing costs. Parameterized models for the strength estimation, as well as calculation of laser manufacturing time and costs, are developed. The models are linked in an optimization workflow and the optimum positioning and shape of the cavities on the joining zone is determined using a genetic optimization algorithm. The results show that, compared to a benchmark, the manufacturing costs can be reduced by 82 % for the same strength using the proposed model-based optimization approach.

The idea of a buried oxide layer (BOx) in a split channel Gate All Around-Tunnel Field Effect Transistor (GAA-TFET) was investigated in this paper. This work examined the impact of buried oxide layer on the device's performance. With the BOx layer present and channel length of 20nm, the channel area of the TFET device investigated in this study is divided equally on the same side. The doping concentration has been transferred to the split channel on the drain side. The device’s performance was examined using numerical simulation utilizing simulation software of CAD devices. The final results which incorporate the buried oxide layer were being compared to the uniform split channel GAA-TFET. The parameters like ON current (Ion),OFF current (Ioff), subthreshold swing (SS) and electric-field (E) intensity are observed and compared with silicon (Si) based GAA-TFET and Indium phosphide (InP) based GAA-TFET. It is found that InP based GAA-TFET with buried oxide layer is more advanced device design than the others with Ion and Ioff of 3.02 x 10-05 A/um and 2.09 x 10-22 A/um, respectively.

The aim of the study was to investigate the effect of process parameters on the production of hydrogels with antisolvent precipitation using unpurified (UB) and purified (PB) birch outer bark betulin powder samples. Experimental activities are focused on the production of hydrogels using concentration of colloidal dispersions with filtration of UB or PB sample particles obtained by antisolvent precipitation method varying the dilution of saturated (at boiling temperature) ethanol solutions with different water content. During the study the maximum solubility in ethanol at boiling point of PB (22.0 g/L) and UB (55.0 g/L) was determined. For obtaining gel with the highest liquid content (absorption capacity 37.45 g per 1 g of dry matter) from PB by antisolvent precipitation the optimal saturated ethanol solution dilution with water was 12.5 vol%. In the case of UB hydrogel, by dilution of ethanol from 25 to 10 vol%, a gradual decrease of hydrogel dry matter yield and a simultaneous increase of the filtrate dry matter yield can be observed, which is related with leaching of the particles through the filter paper together with a solution and form a colloidal suspension of particles. For obtaining gels with high liquid content from UB the optimal saturated ethanol solution dilution with water was in the range from 20.0 to 12.5 vol% (absorption capacity in average 18 g per 1 g of dry matter). Comparing the chemical compositions of the raw materials and dry matter of hydrogels in the case of PB composition remains quite similar while in UB dry matter composition the betulin content increased from 52 to even 69 wt%. PB at the optimal dilution of 12.5 vol% of ethanol managed to achieve average particle size - 231.7 nm and with UB in the optimal dilution range from 20 to 12.5 vol% the range of average particle size was from 304.7 to 189.8 nm.

A novel approach of Micro-electrochemical Texturing (MET) is a realistic substitute for generating surface textures of machined surface. Several conventional and non-conventional techniques i.e., embossing, sand blasting, pinning, LBM, EDM etc. are available for generating microsurface textures, but creates several problems to generate microtextured surfaces which reduce the quality and lower the productivity. To overcome these limitations, this research proposes a unique microsurface texturing method namely, micro-electrochemical texturing, based on electrochemical reaction. Due to the high flexibility of the micro-electrochemical texturing system, micro-texturing features, surface roughness and its performance can be easily changed by varying the micro-electrochemical parameters. In this research paper, this process is developed to fabricate the microsurface textures on stainless steel specimens economically with less time. The experimental results of surface characteristics generated on workpiece utilizing the developed setup with vertical cross flow electrolyte circulation system in micro-electrochemical texturing method are presented. The effects of duty ratio and voltage on performance criteria i.e., material removal rate (MRR), taper kerf angle and surface roughness are investigated. The obtained overall surface roughness value on the stainless-steel samples machined by micro-electrochemical texturing technique is 0.08μm.

Dry EDM is a variation of the standard EDM method in which the liquid dielectric is replaced with a gaseous medium during the machining process. This paper presents comparative analysis of stationary and rotary electrode on Dry EDM in machining of Hastelloy C276 using copper EC grade rod as electrode and air as dielectric medium. Solid cylindrical (stationary and rotary) tool electrodes are used, and high-velocity gas is fed between the electrode and the workpiece through it into the discharge gap. The high-velocity gas flow into the gap assists debris clearance and reduces tool and workpiece overheating at the discharge areas. The dry EDM technique is currently known to have reduced tool wear, a smaller discharge gap, fewer residual stresses, a smaller white layer, and a smaller heat-affected zone, in addition to being ecologically friendly. To improve response factors such as material removal rate (MRR), surface roughness (Ra), and tool wear rate (TWR), Taguchi's L9 orthogonal array approach is utilised to design the trials and study the effects of different process parameters. Discharge current (I), pulse on time (Ton), Voltage (V), pressure (P), and tool rotational speed (N) were the varied input parameters. It is observed that the rotary electrode gives better MRR compared to stationary. The analysis of results show that current (I), pulse on time (Ton) and pulse off time (Toff) are the dominant factors that influence MRR and EWR.