bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aspect related to 3D modelling and finite elements study of the lifting platform
Authors: Muscă(Anghelache) G D , Potîrniche M A , Căpățană G F 
Published: October 2021

Abstract
3D modeling of the lifting platform was done in Catia V5R20 software. This soft was chosen as it gives an integrated solution, besides facilities related to modelling with solids which are common to all representative applications this also offers modules intended for stylists this way allowing extension of computer use also on previous stages of constructive engineering. The truck undercarriage is of LT28 type from Volkswagen producer. For 3D modelling, a leaflet from producing company was used. To represent the assembly of lifting platform firstly we realized a 3D model of the vehicle, and thereafter we realized the model of the nacelle type system and the manner of fixing on undercarriage. The finite elements study of the lifting platform was done by using Autodesk Inventor and for starting we determined the initial conditions type of network and material used. The main boom structure is calculated to stand for all stresses the platform is subject to. The structure is so designed that it can be fixed on the vehicle undercarriage frame. As a result of study, its maximum allowable stresses, travels and safety factor can be noticed. The first finite elements study was done on joint area between lifting platform boom and machine undercarriage, initial conditions were set within the study as follows: material mechanical properties type of performed study, force loading. Further to static study, data related to stresses, deformations and safety factor resulted. Maximum allowable stress in the boom of lifting platform has very small values wherefrom results that this stands a force applied on the other end.
The effects of the bending moment upon the mobile element of CNC Machine Tools with great distance between slides
Authors: Petrea L , Stan Gh 
Published: October 2021

Abstract
CNC Machine Tools with kinematical feed chains with great distance between slides (gantry milling machines, cutting machines, carousel lathes etc.) are utilized extensively for machining large and heavy parts. In this type of machine, we can observe a specific phenomenon where the gravity center of the vertical actuated elements moves in the direction of the balancing force for the mobile elements, causing a bending moment to be induced in the mobile element (the mechanical coupling between the two kinematical feed chains). This effect leads to deformations and in worse case looking of the mobile element during movement, all of this has a detrimental effect on machining accuracy and efficiency. In this paper, using finite element analysis (FEA) several studies where preformed. A static analysis that calculates the stresses, displacements and strains. A modal analysis to determine the first six natural frequencies and modal deformed shapes. A harmonic response analysis to determine the response of the mobile element structure. This studies will highlight the week points of mobile element and will provide the machine tool builder with important information regarding the points that need to be address in order to improve the behavior of the mobile element during actuation.
Heat Transfer Augmentation of Laminar Flow in Horizontal Circular Nano-Composite Tube with Insert
Authors: Qasim M S , Abdulla F A , Nahla H D 
Published: October 2021

Abstract
A numerical investigation was carried out to predict the heat transfer behavior and friction factor in heated circular nano- composite tube with two cases: plain tube and inserted tube. Typical twisted tape (TTT) and triangular cut twisted tape (TCTT) were used as insert if twisted tape ratio equal 2 and thickness equal 1 mm. The composite material consist of polyester resin mixed with nano copper with different weight fraction 3%, 7%, 33%, 50% and 75%. The governing equations were solved by using commercial ANSYS Fluent package (2017) with the assistance of Solid Works and Gambit software program. The finite volume approach was used in solving the equations to predict the pressure flow, heat transfer and temperature distribution along the tube. Nano- composite material tube was heated under constant heat flux (1244W/m2). The water flow in the tube was laminar (297 < Re < 1670). The dimensions of circular tube were 800 mm length, 20 mm diameter and 1.5 mm thickness. Numerical results show that the heat transfers was augmented when (TTT or TCTT) was used as a swirl flow devices comparing with plain tube. The water temperature increases significantly at the center line of tube by 25% when TTT is used, while the friction losses increase in an undesirable rate of 155 %.Finally, it can be concluded that the nano-composite tube is efficient in heat transfer applications.
Concept development and prototypes for robotic systems in active assisted living
Authors: Todirițe I , Radu-Frenț C , Cotfas P-Al , Iliescu M 
Published: October 2021

Abstract
Active and Assistive Living, AAL, is a concept that attention have been focused on in the last decades. There are many young people with disabilities, such as visually impairment, missing limbs, AVC stroke problems. There are also many old people who have locomotion, eyesight and many other health problems that make their lives so very difficult. The authors of this paper present aspects of their research regarding new concepts, models and prototypes (virtual and 3D printed) of robotic systems intended to assist people with disabilities for an active and normal life. An innovative open source system for guidance of young people (but, also elderly ones) with eyesight problems has been developed. It is intended to be used indoors also outdoors, to provide audio guidance, haptic guidance, or both. Research aspects on a bionic prosthesis for the upper limb are evidenced. The focus is on a two fingers model that should be considered as the proof of concept. Innovative mechatronic system designed to help people, who can no longer stand and / or walk is further presented. A virtual platform concept aimed at the integration of all these devices, and similar others, to communicate by IoT is shown.
Novel method suitable for decreasing the roofing tile failures generated during rapid drying
Authors: Vasić M R , Rekecki R , Radojević Z 
Published: October 2021

Abstract
Only few papers in which principles for decreasing the failures generated during semi and rapid drying of porous shrinking materials, for example roofing tiles, are reported. One of the main differences between the traditional and rapid drying regimes is related with the fact that during the heating step products are heated to the much higher temperatures during rapid drying. If the humidity inside the industrial drying tunnels or chambers is not controlled all the time in the prescribed range of 90 - 95 %, especially during the heating step of the rapid drying regime, crack failures will be developed. In order to inhibit the cracks generation during intensive drying the non-ionic surfactant Igepal CO-630 was added in the raw material during forming process. Various amounts of surfactant around the critical micelle concentration (CMC) were used. Five isothermal experiments were recorded, on laboratory extruded roofing tiles, for each surfactant concentration. Calculated effective diffusivity and material strength -moisture ratio (Deff-MR & MS-MR) curves were used to monitor the development of the cracks during drying and to determine the most suitable concentration of the surfactant. The explanation, how the interaction of the surfactants with clay helps the water molecules to easily move up to the surface was also reported. The application of surfactant in a recommended amount has significantly reduced the drying induced fractures in roofing tiles during its intensive drying and consequently the industrial scarp-rate was accordingly lowered.
Heat treatment of 3D printed polyethylene terephthalate glycol in a supporting powder bed
Authors: Zapciu A , Gh Amza C , Baciu F , Vasile M I 
Published: October 2021

Abstract
Material extrusion 3D printing is a fabrication process that produces layered polymer parts with complex geometry but with inferior mechanical properties compared to parts made with other methods such as injection molding. Post fabrication heat treatment is a valid post-processing method that reduces the internal thermal stresses and improves layer adhesion in 3D printed polymers, resulting in superior mechanical properties. This study investigates the mechanical changes produced in 3D printed PETG (polyethylene terephthalate glycol-modified) parts after heat treatment. A novel technique is used, where the parts are embedded into a bed of sodium chloride powder in order to prevent deformation during postprocessing. Fully filled 3D printed PETG parts with various geometries are tightly packed in a bed of powder. The parts are subjected to heat treatment at a temperature above the material’s glass transition temperature but below its melting temperature. Destructive and non-destructive testing performed on the treated 3D printed samples shows a substantial improvement of mechanical properties. Tensile strength testing reveals an increase of tensile strength by 40% for parts printed horizontally and by over 100% for parts printed vertically. Increased stiffness is also observed in treated parts. Compressive strength testing shows a strength increase of 43% after treatment. Dimensional measurements made prior to and after treatment show significantly reduced deformation when using the supporting powder method versus unsupported treatment. Scanning electron microscopy (SEM) analysis is used to assess internal structural changes in the polymer after post-processing. This analysis reveals changes in internal void shape and distribution, increased interlayer adhesion and increased interface area of deposited filaments, providing insight into the mechanisms that lead to the improved properties observed in destructive testing. The supporting powder heat treatment allows the fabrication of parts with complex geometry through material extrusion 3D printing while mitigating the inherent disadvantage of the fabrication process of producing parts with inferior mechanical properties.
Cold in-place recycling of aged and deteriorated asphalt and concrete pavements
Authors: Zghibarcea Ș , Ungureanu D , Țăranu N , Hoha D , Polcovnicu RA , Leizeriuc TA 
Published: October 2021

Abstract
This study focuses on implementing two distinct recycling methods, the reclaimed asphalt pavement and the reclaimed concrete material, on classical road pavements, by totally replacing the surface or base courses with ones made with recovered materials. The majority of the road networks in the eastern European countries were built between 1950 and 1980 and are, nowadays, aged and degraded. Within this frame, the cold in-place recycling methods were developed, which can be applied to both asphalt and concrete pavements. During the cold in-place recycling process, the reclaimed asphalt or concrete materials do not leave the construction site at all, but they are processed on the spot and reused immediately. Thus, the material is granulated to the desired depth, mixed with the binding agent and water and then repaved and compacted in a new layer. One of the most significant benefits of the cold in-place recycling process is that the material is simultaneously recycled and mixed with the binding agent, enabling the road pavement to be strengthened without the need to import expensive virgin aggregates. This work describes the manufacturing technology and the equipment train used to cold recycle aged and deteriorated asphalt and concrete pavements.
Analytical study of the melt pool distortion in the Laser Powder Bed Fusion Process caused by the angle of incidence of the laser and its effect on the surface finish of the part
Authors: Sendino S , Martinez S , Lamikiz A , Lartategui F , Gardon M , Gonzalez J J 
Published: October 2021

Abstract
One of the factors that most affects surface roughness is the angle of incidence of the laser with respect to the platform, which varies across the platform. However, to make the L-PBF process a competitive technology, several parts must be manufactured on the same platform, using maximum building volume. Nevertheless, due to this angle of incidence, even if identical parameters and geometries are used, the surface finish of the parts varies considerably depending on the positioning of the part on the platform. Throughout this work, the effect that this angle of incidence has on the surface of parts manufactured in the different positions of the platform is presented. For this purpose, first the angle of incidence on the whole platform was determined. Then, based on these results, the distortion of the melt pool was analyzed analytically, with the aim of relating the poor surface finish, seen by different technologies such as infinite focus microscope or SEM, with the distortion of the melt pool generated by the angle of incidence.
Methodology for embedding mineral insulated cables into DIN 1.2311 tool steel for the manufacture of smart tooling
Authors: Ostolaza M , Arrizubieta J I , Muro M , Ruiz J E , Artola G , Lamikiz A 
Published: October 2021

Abstract
In the present climate led by industry and digital manufacturing, the implementation of intelligent tooling in manufacturing processes has become imperative. In the case of metal forming processes, this requirement is translated into controlling the material flow and the temperature in the tool-part contact interface. In this manner, not only the mechanical properties of the produced parts are predicted, but also the status of the tooling can be monitored. To that end, a methodology for embedding sensors close to key areas needs to be developed. Additive Manufacturing holds a great potential for enabling such integration. However, high process temperatures inherent to metal AM processes are a limiting factor in this matter. With the aim of taking a step forward in this field, in the present work a methodology for embedding mineral insulated cables into metal forming tooling has been developed. Furthermore, the minimum cable size integrable by means of this technology has been determined and the main limitations of this process exposed. It has been concluded that low energy inputs are necessary to avoid the destruction of the sensorial components and that adaptive process parameters are necessary if sound metal coatings over undamaged components are to be deposited.
Laser engraving of chip-breaker geometry on ceramic cutting tools
Authors: Ukar E , Arrizubieta J I , Ruiz J E , Ostolaza M , Lamikiz A 
Published: October 2021

Abstract
Laser texturing is a process that allows the selective removal of material by applying a high energy density over a small area during a very short time interval. Although it is generally common to use ultra-short pulse (ps or fs) lasers for tool engraving, in certain applications it is possible to use short pulse (ns) lasers. In this work, the material removal rate of an ns laser has been evaluated in chip-breaker milling on Al2O3 cutting inserts reinforced with SiC whiskers. The results obtained show that by milling chip-breaker geometries it is possible to reduce the cutting forces, however, the process parameters used are key to obtain an adequate surface finish without embrittlement of the tool. By means of an adequate design, a reduction in cutting forces of 20% was achieved; additionally, it has been proved that there is a high dependence between tool life and the milling strategy used.
Effect of laser heat treatments on the hardness of tool steels
Authors: Lagarinhos J N , Afonso D , Torcato R , Santos C , Oliveira M 
Published: October 2021

Abstract
The application of laser heat treatments (LHT) has been growing attention in the last years, due to the effectiveness of localized hardening that can improve the tribological properties of steels. AISI P20 mod. steel is commonly used for plastic injection moulds applications and can be heat-treated to achieve high hardness values. This work presents an experimental investigation on the laser local heat treatments effect on the hardness of AISI P20 mod. steel parts, using a high-power diode laser. Different heat treatments at 1060 °C and 1100 °C using a feed rate of 10 mm·s-1 and 15 mm·s-1 were applied on the steel. The LHT were assessed through the hardness mapping trough depth and width. The results showed that the hardness of as-received P20 mod. tool steel is approximately 300 HV, and after LHT occurred an increment to around 625 HV with a fair hardness distribution. LHT had a minimum of 0.8mm and a maximum of 1.0mm depth.
Fused Filament Fabrication over fabrics – experiments and applications
Authors: Legoinha C , Afonso D , Pires L 
Published: October 2021

Abstract
The focus of this paper is to explore the use of Fused Filament Fabrication technology, a material extrusion additive manufacturing technology, by depositing melted Polilactic Acid (PLA) over a substrate – fabric - instead of on an empty building tray. The textile’s composition, nozzle and building plate temperature, printed PLA thickness and printed geometry have been considered as variables that could influence the structural and adhesion properties on this study so, therefor, were took into consideration and tested throughout the printing process through specimens printed with different combined parameters. The aim of this exploration process was developing an experimental procedure to study the limitations and capabilities of this printing technology over textiles, and which different variables’ combination would contribute to a better overall result in the development of a self-supporting textile based structural model, that could be apply in different contexts without the need of any extra external support. Results showed that PLA adherence to the fabric is correlated with nozzle/building plate temperature and printing thickness: higher temperature and thickness provide higher adherence. The weave of the textile didn´t reflect on better results but the polyester felt fabric exhibit maximum adherence with printed PLA in all sets of temperatures. In addition, geometries with reinforcement lines along the fabric stress direction provided better structural results. These results enable new application possibilities for the FFF technology combined in fabrics such as in interior, fashion and shoe ware design.
Experimental measuring of printing speed in FDM
Authors: Dorado R , Pérez F J , Medina G , Guerrero F 
Published: October 2021

Abstract
Fused Deposition Modeling (FDM) technology, based on material extrusion, helps additively manufacture, using cheap printers, stable mechanical parts in different materials. The dimensional deviations and staircase effect are the main drawbacks of this approach and limit its use to prototypes. The linear interpolation used to define the hot-end movements is responsible for continuous speed changes along the tool-path, contributing to dimensional and surface errors. In that sense, the study of the speed profile can help to improve the process. This work explains two printing speed estimation approaches an out-process measurement method, which estimates the average speed as a function of the interpolation segment length and direction, and an in-process method based on encoder measurements. We applied these solutions and an analytical approximation based on a trapezoidal speed profile to a printed 3D Archimedean spiral. All approaches detect abrupt speed changes, potential candidates to produce extrusion-movement synchronization problems, and, therefore, part errors.
Research on desktop 3D Printing Multi-Material New Concepts
Authors: Fenollosa F , Uceda R , Tejo A , Calvo L , Poudelet L , Buj I 
Published: October 2021

Abstract
3D printing or Additive Manufacturing (AM) was originally born as a mono-material technology. And, nowadays, most of the applications are still using only one material. AM has a lot of potential but has not yet been fully explored, and access to the creation of multi-material products is an example of it. One of the most interesting areas is the introduction in the same part of materials with different rigidities, stiffer and softer areas, with differentiated values of mechanical strength and viscoelasticity. In the present work, a general vision of Additive Manufacturing under the vision of mono- and multi-material processes is given, and some existing 3D printing multi-material experiences related to Material Jetting (MJ) and Material Extrusion (ME) are briefly described. But it is in this latter field, linked to Desktop 3D printing (more accessible than typical proprietary industrial equipment), where on-going research could easily be spread: five research ME concepts are then presented, from a revolver print-head to silicone UV 3D printing, with their initial embodiment in the form of prototypes or/and testing, as a way to verify the difficulties that would be encountered in the transition from research to reality.
Supply chain production planning of a manufacturing project system 4.0: case study: Shipbuilding
Authors: Ramirez M , Pérez V , Gómez A , Montaño R , Batista M 
Published: October 2021

Abstract
Projects characterized by high difficulty in terms of planning and administrative control, require the strategies facilitated by Manufacturing Project Systems (MPS). Among them is an adequate management of the Supply Chain used as a competitive strategy. It could be said that in the case of shipbuilding, the Supply Chain is much more complicated due to the number of intervening parties and many shipyards have opted to include Concurrent Engineering with the implication of considering all the elements that make up the product life cycle. The objective of this article is based on the study of the existing applications for the integration of the companies’ management as well as the technological contributions that can collaborate to the integration of the Supply Chain production planning. Getting to identify the seven key technologies of Industry 4.0 that most contribute to the sustainability of shipbuilding.
Uncertainty determination of a microvolume characterized through confocal microscope technique
Authors: Berzal M , Barajas C , Christopher J M , Santamaría B , Munoz D 
Published: October 2021

Abstract
Standardized measurements protocols are widely used and necessary in order to ensure a relivable and repetitive data. This work introduces a new procedure to measure the volume of any irregular micro-hole on a rough surface. A filtering and fitting model is proposed for calculating the void volume of the cavity. Experimental point cloud is acquired by optically measuring the micro-hole with a confocal microscope. RANSAC algorithm is used to establish the reference plane, while the limits of the cavity and the volume are determined by a proposed algorithm. The mentioned model is validated by measuring six real samples. In addition, the corresponding uncertainty is estimated by using Monte Carlo method.