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Mr. Sergio Martín-Béjar
Universidad de Málaga, Spain

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0 Machining
0 UAV
0 Aluminium Alloy
0 Turning
0 Heritage

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Journal article
Published: 13 June 2021 in Metals
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Geometrical tolerances play a very important role in the functionality and assembly of parts made of light alloys for aeronautical applications. These parts are frequently machined in dry conditions. Under these conditions, the tool wear becomes one of the most important variables that influence geometrical tolerances. In this work, the influence of tool wear on roundness, straightness and cylindricity of dry-turned UNS A97075 alloy has been analyzed. The tool wear and form deviations evolution as a function of the cutting parameters and the cutting time has been assessed. In addition, the predominant tool wear mechanisms have been checked. The experimental results revealed that the indirect adhesion wear (BUL and BUE) was the main tool-wear mechanism, with the feed being the most influential cutting parameter. The combination of high feed and low cutting speed values resulted in the highest tool wear. The analyzed form deviations showed a general trend to increase with both cutting parameters. The tool wear and the form deviations tend to increase with the cutting time only within the intermediate range of feed tested. As the main novelty, a relationship between the cutting parameters, the cutting time (and, indirectly, the tool wear) and the analyzed form deviations has been found.

ACS Style

Francisco Trujillo Vilches; Sergio Martín Béjar; Carolina Bermudo Gamboa; Manuel Herrera Fernández; Lorenzo Sevilla Hurtado. Influence of Tool Wear on Form Deviations in Dry Machining of UNS A97075 Alloy. Metals 2021, 11, 958 .

AMA Style

Francisco Trujillo Vilches, Sergio Martín Béjar, Carolina Bermudo Gamboa, Manuel Herrera Fernández, Lorenzo Sevilla Hurtado. Influence of Tool Wear on Form Deviations in Dry Machining of UNS A97075 Alloy. Metals. 2021; 11 (6):958.

Chicago/Turabian Style

Francisco Trujillo Vilches; Sergio Martín Béjar; Carolina Bermudo Gamboa; Manuel Herrera Fernández; Lorenzo Sevilla Hurtado. 2021. "Influence of Tool Wear on Form Deviations in Dry Machining of UNS A97075 Alloy." Metals 11, no. 6: 958.

Conference paper
Published: 01 February 2021 in IOP Conference Series: Materials Science and Engineering
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Aluminum alloys, particularly series 2000 (Al-Cu) and 7000 (Al-Zn), are widely used for structural elements in aircraft. Machining processes are frequently applied in manufacturing these parts. The actual trend in the machining of these components is to reduce or eliminate the use of lubricants, due to environmental reasons. Among the different techniques, dry machining is commonly used for aluminum alloys. However, dry machining generates higher severe cutting conditions, which may negatively affect the surface integrity and the mechanical properties of the machined parts. In this regard, fatigue life is one of the most important mechanical properties to take into account. Micro-cracks generation and nucleation strongly depend on the surface conditions of the machined parts. Additionally, the addition of Zn to pure aluminum (7000 series) reduces the corrosion resistance. Despite its importance, there is a lack of research devoted to analyze the cutting parameters influence on fatigue behaviour, before and after corrosion, in dry machining of these alloys. Therefore, in this work, the cutting speed and feed rate influence on fatigue behaviour of the UNS A97075 (Al-Zn) alloy has been analyzed. Several rotating bar bending fatigue tests have been carried out, studying and comparing the fatigue life curves obtained as a function of the cutting parameters, before and after an immersion corrosion process. The experimental results have revealed that an increment in the cutting speed and feed rate gives rise to fatigue life reduction.

ACS Style

S Martín-Béjar; F J Trujillo; C Bermudo; M Herrera; L Sevilla. Cutting parameters influence analysis on fatigue behaviour of dry turned UNS A97075 alloy after corrosion. IOP Conference Series: Materials Science and Engineering 2021, 1037, 012012 .

AMA Style

S Martín-Béjar, F J Trujillo, C Bermudo, M Herrera, L Sevilla. Cutting parameters influence analysis on fatigue behaviour of dry turned UNS A97075 alloy after corrosion. IOP Conference Series: Materials Science and Engineering. 2021; 1037 (1):012012.

Chicago/Turabian Style

S Martín-Béjar; F J Trujillo; C Bermudo; M Herrera; L Sevilla. 2021. "Cutting parameters influence analysis on fatigue behaviour of dry turned UNS A97075 alloy after corrosion." IOP Conference Series: Materials Science and Engineering 1037, no. 1: 012012.

Journal article
Published: 09 December 2020 in Applied Sciences
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As a typology of cultural heritage, a wide range of singularities must to be taken into account when analysing industrial heritage assets. Graphical resources have been usually employed in heritage assets research. Nowadays, Unmanned Aerial Vehicles (UAVs) offer the possibility to obtain images of complex and difficult access areas that cannot be observed on the ground. Furthermore, aerial images allow to analyse heritage assets as a whole. Therefore, in this work, different photographs and videos has been carried out in the San Joaquin sugar cane factory and in the Aguila aqueduct, located in Nerja (Spain). These images have been used to analyse both assets as a set. Different indirect measurements on the factory chimney and irrigation water pond were taken. A Strengths, Weaknesses, Opportunities, and Threats (SWOT) about the use of UAV graphic applications in heritage assets was developed. Finally, the possibilities of conventional photograph technologies and UAV application were compared. Using UAVs allows more image acquisition possibilities than conventional systems. However, both technologies can be complemented and applied together when analysing heritage assets.

ACS Style

Sergio Martín-Béjar; Juan Claver; Miguel A. Sebastián; Lorenzo Sevilla. Graphic Applications of Unmanned Aerial Vehicles (UAVs) in the Study of Industrial Heritage Assets. Applied Sciences 2020, 10, 8821 .

AMA Style

Sergio Martín-Béjar, Juan Claver, Miguel A. Sebastián, Lorenzo Sevilla. Graphic Applications of Unmanned Aerial Vehicles (UAVs) in the Study of Industrial Heritage Assets. Applied Sciences. 2020; 10 (24):8821.

Chicago/Turabian Style

Sergio Martín-Béjar; Juan Claver; Miguel A. Sebastián; Lorenzo Sevilla. 2020. "Graphic Applications of Unmanned Aerial Vehicles (UAVs) in the Study of Industrial Heritage Assets." Applied Sciences 10, no. 24: 8821.

Journal article
Published: 12 May 2020 in Metals
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Fatigue behavior takes special relevance in structural parts for aircraft due to safety reasons. Despite its environmental advantages, dry machining of these parts may negatively affect their surface integrity, which may lead to a reduction in fatigue life. Nevertheless, there is a lack of research focused on the analysis of the cutting parameters influence on fatigue behavior in dry machining of aeronautical aluminum alloys, in spite of its importance. Therefore, in this work, an analysis of the cutting speed and feed influence on fatigue behavior of dry turned UNS A97075-T6 alloy is presented. The stress-fatigue life curves have been obtained and corrected according to the applied cutting parameters values. Additionally, the surface roughness and two macro-geometrical deviations (cylindricity and concentricity) have been controlled. The experimental results have revealed that fatigue life is reduced when high values of cutting speed and feed are combined. Finally, a parametric potential equation for fatigue life, as a function of the load and the cutting parameters, has been developed. The relation has been obtained for the theoretical fracture section and, as the main novelty, corrected for the real one.

ACS Style

Sergio Martín Béjar; Francisco Javier Trujillo Vilches; Carolina Bermudo Gamboa; Lorenzo Sevilla Hurtado. Fatigue Behavior Parametric Analysis of Dry Machined UNS A97075 Aluminum Alloy. Metals 2020, 10, 631 .

AMA Style

Sergio Martín Béjar, Francisco Javier Trujillo Vilches, Carolina Bermudo Gamboa, Lorenzo Sevilla Hurtado. Fatigue Behavior Parametric Analysis of Dry Machined UNS A97075 Aluminum Alloy. Metals. 2020; 10 (5):631.

Chicago/Turabian Style

Sergio Martín Béjar; Francisco Javier Trujillo Vilches; Carolina Bermudo Gamboa; Lorenzo Sevilla Hurtado. 2020. "Fatigue Behavior Parametric Analysis of Dry Machined UNS A97075 Aluminum Alloy." Metals 10, no. 5: 631.

Journal article
Published: 05 February 2020 in Applied Sciences
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In this work, an analysis of the cutting speed and feed influence on surface roughness and microhardness of UNS A97075-T6 alloy, turned under dry conditions, was carried out. The results were compared before and after a corrosion process. The influence of these cutting parameters on each of these variables was analyzed, as well as the possible interrelation between them. The microgeometrical deviations showed a general trend to increase with feed. However, no significant modifications were observed as a function of the cutting speed. This trend was softer after the corrosion process, due to the surface alterations produced by pitting corrosion, which resulted in higher dispersion of the experimental data. In addition, a surface microhardness increment was observed in all samples, after machining and before corrosion, regardless of the cutting parameter values. The experimental results revealed that the mechanical effects, produced by the feed, should not be neglected against the thermal effects, produced by the cutting speed, within the range of the tested cutting speed. Finally, the corrosion process negatively affected the microhardness, but it was not possible to establish a direct relationship between the cutting parameters, surface roughness, and microhardness after a corrosion process.

ACS Style

Sergio Martín-Béjar; Francisco Javier Trujillo Vilches; Carolina Bermudo Gamboa; Lorenzo Sevilla Hurtado. Cutting Speed and Feed Influence on Surface Microhardness of Dry-Turned UNS A97075-T6 Alloy. Applied Sciences 2020, 10, 1049 .

AMA Style

Sergio Martín-Béjar, Francisco Javier Trujillo Vilches, Carolina Bermudo Gamboa, Lorenzo Sevilla Hurtado. Cutting Speed and Feed Influence on Surface Microhardness of Dry-Turned UNS A97075-T6 Alloy. Applied Sciences. 2020; 10 (3):1049.

Chicago/Turabian Style

Sergio Martín-Béjar; Francisco Javier Trujillo Vilches; Carolina Bermudo Gamboa; Lorenzo Sevilla Hurtado. 2020. "Cutting Speed and Feed Influence on Surface Microhardness of Dry-Turned UNS A97075-T6 Alloy." Applied Sciences 10, no. 3: 1049.

Journal article
Published: 11 December 2019 in Materials
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Nowadays, localized forming operations, such as incremental forming processes, are being developed as an alternative to conventional machining or forming techniques. An indentation process is the main action that takes places in these forming activities, allowing small, localized deformations. It is essential to have the knowledge of the material behavior under the punch and the transmitted forces to achieve correct control of the entire procedure. This paper presents the work carried out with the digital image correlation (DIC) technique applied to the study of the material flow that takes place under an indentation process. The material flow analysis is performed under 2D and 3D conditions, establishing the methodology for the calibration and implementation for each alternative. Two-dimensional DIC has been proven to be a satisfactory technique compared with the 3D method, showing results in good agreement with experimental tests and models developed by the finite element method. Notwithstanding, part of the indented material flows under the punch, emerging on the front surface and generating a dead zone that can only be addressed with a 3D technique. So, the main objective is to carry out a comparison between the 2D and 3D techniques to identify if the 3D application could be mandatory for this type of process. Also, a 2D–3D mix analysis is proposed for study cases in which it is necessary to know the material flow in that specific area of the workpiece.

ACS Style

Carolina Bermudo Gamboa; Sergio Martín-Béjar; F. Javier Trujillo Vilches; G. Castillo López; Lorenzo Sevilla Hurtado. 2D–3D Digital Image Correlation Comparative Analysis for Indentation Process. Materials 2019, 12, 4156 .

AMA Style

Carolina Bermudo Gamboa, Sergio Martín-Béjar, F. Javier Trujillo Vilches, G. Castillo López, Lorenzo Sevilla Hurtado. 2D–3D Digital Image Correlation Comparative Analysis for Indentation Process. Materials. 2019; 12 (24):4156.

Chicago/Turabian Style

Carolina Bermudo Gamboa; Sergio Martín-Béjar; F. Javier Trujillo Vilches; G. Castillo López; Lorenzo Sevilla Hurtado. 2019. "2D–3D Digital Image Correlation Comparative Analysis for Indentation Process." Materials 12, no. 24: 4156.

Journal article
Published: 24 October 2019 in Metals
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Macro-geometrical deviations play a very important role in the functionality and reliability of structural parts for aircraft. The use of environmentally friendly techniques, such as dry machining, may negatively affect these deviations. Despite its importance, there is a lack of research that analyzes them as a function of the cutting parameters in the case of aluminum alloys for aeronautical purpose. In this work, the cutting speed and feed influence on several macro-geometrical deviations (parallelism, straightness, circular run-out, roundness, concentricity, total circular run-out and cylindricity) in dry turning of UNS A97075 alloy was analyzed. The main novelty of this work lies in the use of high slenderness parts used in further fatigue tests. The results showed that feed seems to be the most influential parameter in most of the deviations studied. In addition, the parts with lower rigidity exhibited higher sensitivity to change with the cutting parameters. Finally, different parametric models were proposed to obtain the geometrical deviations as a function of the cutting parameters.

ACS Style

Sergio Martín Béjar; Francisco Javier Trujillo Vilches; Carolina Bermudo Gamboa; Lorenzo Sevilla Hurtado. Parametric Analysis of Macro-Geometrical Deviations in Dry Turning of UNS A97075 (Al-Zn) Alloy. Metals 2019, 9, 1141 .

AMA Style

Sergio Martín Béjar, Francisco Javier Trujillo Vilches, Carolina Bermudo Gamboa, Lorenzo Sevilla Hurtado. Parametric Analysis of Macro-Geometrical Deviations in Dry Turning of UNS A97075 (Al-Zn) Alloy. Metals. 2019; 9 (11):1141.

Chicago/Turabian Style

Sergio Martín Béjar; Francisco Javier Trujillo Vilches; Carolina Bermudo Gamboa; Lorenzo Sevilla Hurtado. 2019. "Parametric Analysis of Macro-Geometrical Deviations in Dry Turning of UNS A97075 (Al-Zn) Alloy." Metals 9, no. 11: 1141.

Journal article
Published: 01 January 2019 in Procedia Manufacturing
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Geometrical deviations play a very important role in machining of aircraft structural parts. These components are placed in critical areas and, therefore, their quality requirements are very demanding. Geometrical deviations may affect not only to the assembly process but also to the mechanical properties, fatigue behaviour among them. Notwithstanding, there is a lack of research regarding the analysis of cutting parameters influence on macro-geometrical deviations, despite their importance in the surface integrity of machined parts. Therefore, this work aims to evaluate the influence of feed and cutting speed on several geometrical deviations (circular run-out, total run-out, concentricity and roundness) of dry turned specimens of UNS A97075-T6 (Al-Zn) aluminium alloy. The experimental results have revealed that feed is the most influential parameter on the geometrical deviations studied. Its effect is enhanced with the use of high cutting speed values.

ACS Style

S. Martín-Béjar; F.J. Trujillo; C. Bermudo; L. Sevilla. Cutting parameters influence on total run-out of dry machined UNS A97075 alloy parts. Procedia Manufacturing 2019, 41, 835 -842.

AMA Style

S. Martín-Béjar, F.J. Trujillo, C. Bermudo, L. Sevilla. Cutting parameters influence on total run-out of dry machined UNS A97075 alloy parts. Procedia Manufacturing. 2019; 41 ():835-842.

Chicago/Turabian Style

S. Martín-Béjar; F.J. Trujillo; C. Bermudo; L. Sevilla. 2019. "Cutting parameters influence on total run-out of dry machined UNS A97075 alloy parts." Procedia Manufacturing 41, no. : 835-842.