9 research outputs found
Defect Analysis and Detection of Cutting Regions in CFRP Machining Using AWJM
The use of composite materials with a polymeric matrix, concretely carbon fiber reinforced
polymer, is undergoing further development owing to the maturity reached by the forming processes
and their excellent relationship in terms of specific properties. This means that they can be
implemented more easily in di erent industrial sectors at a lower cost. However, when the
components manufactured demand high dimensional and geometric requirements, they must be
subjected to machining processes that cause damage to the material. As a result, alternative methods
to conventional machining are increasingly being proposed. In this article, the abrasive waterjet
machining process is proposed because of its advantages in terms of high production rates, absence
of thermal damage and respect for the environment. In this way, it was possible to select parameters
(stand-o distance, traverse feed rate, and abrasive mass flow rate) that minimize the characteristic
defects of the process such as taper angle or the identification of di erent surface quality regions in
order to eliminate striations caused by jet deviation. For this purpose, taper angle and roughness
evaluations were carried out in three di erent zones: initial or jet inlet, intermediate, and final or jet
outlet. In this way, it was possible to characterize di erent cutting regions with scanning electronic
microscopy (SEM) and to distinguish the statistical significance of the parameters and their e ects on
the cut through an analysis of variance (ANOVA). This analysis has made it possible to distinguish
the optimal parameters for the process
Characterization and Defect Analysis of Machined Regions in Al-SiC Metal Matrix Composites Using an Abrasive Water Jet Machining Process
Metal matrix composite (MMC) materials are increasingly used in industrial sectors such as energy, structural, aerospace, and automotive. This is due to the improvement of properties by the addition of reinforcements. Thus, it is possible to obtain properties of higher strength, better rigidity, controlled thermal expansion, and elevated wear resistance. However, due to the extreme hardness achieved during their manufacture, these composites pose a challenge to the conventional machining industry due to the rapid deterioration experienced by cutting tools. This article therefore proposes the use of an unconventional machining method that is becoming increasingly widely used: abrasive water jet cutting. This process is characterized by high production rates, absence of wear, and environmental friendliness, among other advantages. Experimental tests were carried out in order to analyze results that minimize the formation of defects in the machining of metal matrix composite consisting of aluminium matrix with silicon carbide (Al-SiC MMC). To this end, results were analyzed using Scanning Optical and Electron Microscope (SOM/SEM) techniques, the taper angle was calculated, and areas with different surface quality were detected by measuring the roughness
Evaluation of Reliefs’ Properties on Design of Thermoformed Packaging Using Fused Deposition Modelling Moulds
The increased consumption of food requiring thermoformed packaging implies that the
packaging industry demands customized solutions in terms of shapes and sizes to make each
packaging unique. In particular, food industry increasingly requires more transparent packaging,
with greater clarity and a better presentation of the product they contain. However, in turn, the
differentiation of packaging is sought through its geometry and quality, as well as the arrangement of
food inside the packaging. In addition, these types of packaging usually include ribs in the walls to
improve their physical properties. However, these ribs also affect the final aesthetics of the product.
In accordance with this, this research study analyses the mechanical properties of different relief
geometries that can affect not only their aesthetics but also their strength. For this purpose, tensile and
compression tests were carried out using thermoformed PET sheets. The results provide comparative
data on the reliefs studied and show that there are differences in the mechanical properties according
to shape, size and disposition in the package
On the Machinability of an Al-63%SiC Metal Matrix Composite
This paper presents a preliminary study of aluminium matrix composite materials during
machining, with a special focus on their behavior under conventional processes. This work will
expand the knowledge of these materials, which is considered to be strategic for some industrial
sectors, such as the aeronautics, electronics, and automotive sectors. Finding a machining model
will allow us to define the necessary parameters when applying the materials to industry. As a
previous step of the material and its machining, an experimental state-of-the-art review has been
carried out, revealing a lack of studies about the composition and material properties, processes,
tools, and recommended parameters. The results obtained and reflected in this paper are as follows;
SiC is present in metallic matrix composite (MMC) materials in a very wide variety of sizes. A
metallographic study of the material confirms the high percentage of reinforcement and very high
microhardness values registered. During the machining process, tools present a very high level of
wear in a very short amount of time, where chips are generated and arcs are segmented, revealing the
high microhardness of the material, which is given by its high concentration of SiC. The chip shape is
the same among other materials with a similar microhardness, such as Ti or its alloys. The forces
registered in the machining process are quite di erent from conventional alloys and are more similar
to the values of harder alloys, which is also the case for chip generation. The results coincide, in part,
with previous studies and also give new insight into the behavior of this material, which does not
conform to the assumptions for standard metallic materials, where the hypothesis of Sha er is not
directly applicable. On the other hand, here, cutting forces do not behave in accordance with the
traditional model. This paper will contribute to improve the knowledge of the Al-63%SiC MMC itself
and the machining behavior
Custom Design of Packaging through Advanced Technologies: A Case Study Applied to Apples
In the context of food packaging design, customization enhances the value of a product
by meeting consumer needs. Personalization is also linked to adaptation, so the properties of
the packaging can be improved from several points of view: functional, aesthetic, economic and
ecological. Currently, functional and formal properties of packaging are not investigated in depth.
However, the study of both properties is the basis for creating a new concept of personalized and
sustainable product. In accordance with this approach, a conceptual design procedure of packaging
with personalized and adapted geometries based on the digitization of fresh food is proposed in
this work. This study is based on the application of advanced technologies for the design and
development of food packaging, apples in this work, in order to improve the quality of the packaging.
The results obtained show that it is possible to use advanced technologies in the early stages of
product design in order to obtain competitive products adapted to new emerging needs
Sustainability in the Aerospace, Naval, and Automotive Supply Chain 4.0: Descriptive Review
The search for sustainability in the Supply Chain (SC) is one of the tasks that most concerns business leaders in all manufacturing sectors because of the importance that the Supply Chain has as a transversal tool and due to the leading role that it has been playing lately. Of all the manufacturing sectors, this study focuses on the aerospace, shipbuilding, and automotive sectors identified as transport. The present study carries out a descriptive review of existing publications in these three sectors in relation to the sustainability of the Supply Chain in its 4.0 adaptation as an update in matters that are in constant evolution. Among the results obtained, Lean practices are common to the three sectors, as well as different technologies focused on sustainability. Furthermore, the results show that the automotive sector is the one that makes the greatest contribution in this sense through collaborative programs that can be very useful to the other two sectors, thus benefiting from the consequent applicable advantages. Meanwhile, the Aerospace and Shipbuilding sectors do not seem to be working on promoting a sustainable culture in the management of the Supply Chain or on including training programs for their personnel in matters related to Industry 4.0
Influence of 3D-Printed TPU Properties for the Design of Elastic Products
The design of products with elastic properties is a paradigm for design engineers because the properties of the material define the correct functionality of the product. Fused filament fabrication (FFF) allows for the printing of products in thermoplastic polyurethanes (TPU). Therefore, it offers the ability to design elastic products with the freedom of forms that this technology allows and also with greater variation of elastic properties than with a conventional process. The internal structures and the variation in thickness that can be used facilitate the design of products with different elastic realities, producing variations in the elasticity of the product with the same material. This work studies the influence of the variation of internal density as a function of basic geometries in order to quantify the difference in elasticity produced on a product when it is designed. Likewise, a case study was carried out with the creation of a fully elastic computer keyboard printed in 3D. The specimens were subjected to compression to characterize the behavior of the structures. The tests showed that the elasticity varies depending on the orientation and geometry, with the highest compressive strength observed in the vertical orientation with 80% lightening. In addition, the internal lightening increases the elasticity progressively but not uniformly with respect to the solid geometry, and also the flat faces favour the reduction in elasticity. This study classifies the behavior of TPU with the aim of being applied to the design and manufacture of products with specific properties. In this work, a totally flexible and functional keyboard was designed, obtaining elasticity values that validate the study carried out.The APC was funded by University of Cadiz (programme for the promotion and encouragement of research and transfer)
Influence of AbrasiveWaterjet Parameters on the Cutting and Drilling of CFRP/UNS A97075 and UNS A97075/CFRP Stacks
The incorporation of plastic matrix composite materials into structural elements of
the aeronautical industry requires contour machining and drilling processes along with metallic
materials prior to final assembly operations. These operations are usually performed using
conventional techniques, but they present problems derived from the nature of each material that
avoid implementing One Shot Drilling strategies that work separately. In this work, the study
focuses on the evaluation of the feasibility of AbrasiveWaterjet Machining (AWJM) as a substitute for
conventional drilling for stacks formed of Carbon Fiber Reinforced Plastic (CFRP) and aluminum
alloy UNS A97050 through the study of the influence of abrasive mass flow rate, traverse feed rate and
water pressure in straight cuts and drills. For the evaluation of the straight cuts, Stereoscopic Optical
Microscopy (SOM) and Scanning Electron Microscopy (SEM) techniques were used. In addition, the
kerf taper through the proposal of a new method and the surface quality in different cutting regions
were evaluated. For the study of holes, the macrogeometric deviations of roundness, cylindricity and
straightness were evaluated. Thus, this experimental procedure reveals the conditions that minimize
deviations, defects, and damage in straight cuts and holes obtained by AWJM
Effects of Laser Microtexturing on the Wetting Behavior of Ti6Al4V Alloy
Surface modification procedures by laser techniques allow the generation of specific topographies and microstructures that enable the adaptation of the external layers of materials for specific applications. In laser texturing processes, it is possible to maintain control over the microgeometry and dimensions of the surface pattern through varying the processing parameters. One of the main areas of interest in the field of surface modification treatments is the ability to generate topographies that are associated with specific surface finishes, in terms of roughness, that can improve the manufactured part’s functional capabilities. In this aspect, several types of phenomena have been detected, such as the friction and sliding wear behavior or wetting capacity, which maintain a high dependence on surface roughness. In this research, surface texturing treatments have been developed by laser techniques through using the scanning speed of the beam (Vs) as a control parameter in order to generate samples that have topographies with different natures. Through assessments of surface finish using specialized techniques, the dimensional and geometrical features of the texturized tracks have been characterized, analyzing their influence on the wetting behavior of the irradiated layer. In this way, more defined texturing grooves has been developed by increasing the Vs, which also improves the hydrophobic characteristics of the treated surface. However, due to the lack of uniformity in the solidification process of the irradiated area, some deviations from the expected trends and singular points can be observed. Using the contact angle method to evaluate the wetting behavior of the applied treatments found increases in the contact angle values for high texturing speeds, finding a maximum value of 65.59° for Vs = 200 mm/s