Papers by Keyword: Manufacturing

Abstract: Robotic arms significantly help automate production processes, which is why they are important for Industry 4.0. Depending on production requirements, each operation is matched to a type of robotic arm, as they have specific and unique characteristics. A well-defined classification of robotic arms is fundamental to ensure proper selection, use, and maintenance according to the particular operations performed. This paper presents a classification of the main robotic arms used in logistics and production processes. It also summarizes the main research on the use of robotic arms in logistics and manufacturing.

Abstract: Flax fibre–reinforced polymers (FFRPs) are attractive for lightweight structures due to their low density, favourable specific stiffness and partially bio-based origin. However, their performance is strongly affected by manufacturing route, porosity and moisture uptake, which are typically more critical than for conventional glass or carbon fibre composites. This study compares flax, glass, carbon and carbon–flax hybrid epoxy laminates produced by vacuum infusion, hand lay-up and autoclave prepreg processing. Fibre volume fraction and void content are determined from density measurements, optical microscopy and X-ray computed tomography. Tensile and flexural properties are measured according to EN ISO 527-4 and EN ISO 14125 in the dry state and after accelerated conditioning at 35 ± 2 °C and 100 % relative humidity. Infused unidirectional flax laminates reach a tensile strength of about 259 MPa and a specific tensile strength of approximately 0.21 MPa·m³·kg⁻¹, comparable to glass laminates. Moisture exposure increases thickness by 11.8–13.9 % for infused flax laminates and about 2.3 % for an infused carbon–flax hybrid laminate and leads to strength reductions up to roughly 30 % in flax-rich laminates, while autoclave-processed laminates show only minor losses. The results provide process-dependent design guidelines for FFRPs in moisture-exposed, weight-sensitive components.

Abstract: During metal machining, under certain conditions, vibrations occur, both at the cutting tool, at the workpiece and at the machine tool. The appearance of vibrations during the cutting process is troublesome, because vibrations reduce the durability of cutting tools (especially in tools with inserts). It also increases machine tool wear and worsens the quality of the machined surface (roughness). The problem of vibration is vast and will represent a permanent research topic for tool makers, machine tool builders and process engineers. This paper presents the study and finite element analysis of the vibrations of a cutting tool, a tool used in the longitudinal turning process, both for deburring and finishing operations. The behavior of the tool, the natural frequencies and the elastic deformations that lead to the impairment of the processing precision and the quality of the surface obtained after processing were demined by calculation. We believe that this study is useful both to the manufacturers of cutting tools, but especially to the technological engineers, for the optimization of the process, by avoiding the cutting parameters that lead to resonance with the tool's own frequencies.

Abstract: This work presents interesting results on the manufacturing and mechanical response of new mixtures for geopolymeric mortars using soils collected from sites near the Khapia hill located in the Puno region (Peru). Four types of soils were collected and used as binder raw material within a geopolymeric mortar mixture with a binder: sand ratio of 1:3. In parallel and for comparative purposes, the mechanical response of conventional Portland cement mortars was manufactured and evaluated, with a binder: fine sand volumetric ratio also of 1:3. To obtain the geopolymeric mortars, the sodium hydroxide solution with a molarity of 12 was considered as the liquid phase. While for the conventional Portland cement mortar, water was used. For all cases, the liquid phase: binder ratio was 0.6. The mechanical results were variable, with maximum average mechanical strength values between 30.1 and 45.4 MPa for geopolymeric mortars and 37.4 MPa for conventional mortars. On the other hand, Young's modulus values were found between 5.9 and 10.4 GPa for geopolymeric mortars and 8.8 GPa for conventional mortars. Regarding the porosity estimated from real and apparent densities, values between 27.2 and 28.3 % were found for geopolymeric mortars and 30.2 % for conventional mortars. The microstructure found for both types of mortars studied was very similar, all mortars consisted of two well-identified phases, a continuous and homogeneous phase of binder (geopolymeric or Portland cement) that surrounded another dispersed phase of aggregate particles (fine sand).

Abstract: The grinding technologies are widely used for finishing operations of various types of parts to provide better surface roughness and accuracy for the selected surfaces. Those technologies are expensive and take a lot of time to execute them consequently they are used when it is reasoned. The goal of this research is to compare the manufacturing design processes for horizontal and vertical grinding where the arrangement distinction between them is just the position of the tool axis compared to the machined surface of the workpiece. All of the necessary manufacturing parameters are determined to ease the design process. After the manufacturing design CAM design and CNC program writing are possible if CNC controlled machine is applied. Using of the same manufacturing parameters a comparative manufacturing analysis is done to determine the differences between the two processes.

Abstract: This work aims to perform a scientific mapping using advanced tools and R libraries to evaluate from a quantitative and qualitative point of view the evolution of the field of Additive Manufacturing (AM). A descriptive analysis of the data will be applied for the creation of attributes that allow its normalization and the visualization of its temporal evolution, as well as the measurement of the impact of the sources and the frequency of publication using Lotka's law. With all this, the weight and importance of AM in the evolution of different fields (materials science, engineering, computer science, etc.) will be established and the trend in research work will be analyzed both quantitatively (evolution of the number of publications in each field, quantitative impact indexes of publications and qualitatively. All this will allow the reader to know, on the one hand, the temporal evolution of advanced in AM, and on the other hand, the reader will be able to have a "still picture" of the current situation that can be taken as references for the prospective analysis of the technique in a complementary way to that provided in business studies.

Abstract: Surface marks, such as scratches or cosmetic marks, commonly appear during the manufacturing phase of metallic components, because of the contact between tools and sharp edges with the surface of the parts. Scratches, depending on their width, depth, and root radius, cause a decrease in the fatigue life of metallic alloys. In particular, the presence of scratches with a size comparable to the grain size favors the generation of fatigue cracks in these features. In the aerospace industry, the presence of surface marks is a common cause of rejection. The low hardness of aluminium, a material widely employed in the manufacture of aerospace structures, contributes to the generation of surface marks. In this paper, a preliminary geometrical characterisation of scratches is established. It aims to define a set of parameters to characterise exhaustively the different scratches and to generate different behavior models for each type of scratch. Parameters such as scratch length, path radius, and burr height are considered in addition to the well-known parameters such as scratch depth, root radius, and open angle.

Abstract: One of the problems in orthodontic treatment is friction. Some of the factors that support friction are archwire material, archwire dimensions, bracket material, surface roughness, type of ligation, environmental humidity, and bracket position, angulation angle between bracket and wire, changes in the surface of the archwire and bracket. The aim of this study is to analyse the difference in friction between the two branded bracket designs and a new patented bracket (patent no. IDP000069597). The production method for this new bracket is different, however, uses the same material of 17-4 PH stainless steel. There are three groups in this research, one sample of bracket each from two different branded and one sample of a new bracket design. All three groups were tested for microstructure, then tested for measurement of friction between bracket slots and archwire. The microstructure of the two branded brackets has a martensitic phase that is not as dense as the new bracket, which is due to the different manufacturing method processes. The two branded brackets use the metal injection molding method, while the new brackets use the investment casting method. The friction test results show that there are significant differences between the three groups of brackets. One of the branded brackets (A) has the lowest friction, but branded bracket (B) does not have different friction with the new bracket. Differences in design and manufacturing methods of orthodontic bracket affect the friction between orthodontic brackets and archwires even though they use the same material.

Abstract: The sandwich structure with foldcore is a new type of structural material with light weight, high specific strength, high specific rigidity and multi-functional potential, which is connected with each other in core space, this kind of three dimensional structures can be formed by folding based on two dimensional materials. The main research achievements and characteristics of sandwich structure with foldcore in recent years are summarized and analyzed according to the lightweight and multi-functional requirements of aircraft structure in this paper. The configuration optimization scheme and fabrication process of the sandwich structure with foldcore are described. Moreover, the research status of multi-function of the sandwich structure with foldcore are summarized, including sound insulation, thermal protection, stealth performance of the structure, etc.

Abstract: The research of fluid inclusion thin section is to understand the physical and chemical conditions (such as temperature, pressure, density, pH value, composition, etc.) of minerals, rocks and deposits, and to solve the genesis of rocks and deposits; in the process of production, gas inclusions or liquid inclusions should be produced at low temperature, otherwise the inclusions will be destroyed, especially quartz sandstone, weathered rock, mudstone and other minerals Therefore, when the film is made in a humid temperature environment, it is very easy to be deliquesced, especially for the rocks with developed cleavage and many cracks, after rough grinding after polishing, it is easy to produce warping edge, warping angle, bubbles, etc., thus causing the sample piece to deteriorate after polishing; therefore, a large number of pockmarks and cracks will be produced under the microscope. In this paper, starting from the applicable conditions of materials and technological methods, the practical problems of making materials and technological process in rock slice method are introduced in detail. Keywords Inclusion,Manufacturing, Grinding,Polishing,Filming