Término solicitado: SIMONCELLI, ALEJANDRO/(22)
2 Registro/s encontrado/s en CAT+NORMA
| Tipo de Docum.: | artículo |
| Título: | Reduction of die wear and structural defects of railway screw spike heads estimated by FEM |
| Autor: | Alcázar, Jackeline; Abate, Germán; Antunez, Nazareno; Simoncelli, Alejandro; Sánchez Egea, Antonio J.; Martinez Krahmer, Daniel; López de Lacalle, Norberto |
| Título Ser./Col.: | Nanomaterials, 11(11) |
| Autor Inst. Ser./Col.: | Multidisciplinary Digital Publishing Institute. MDPI. Basilea. Suiza |
| Idioma: | eng |
| Datos de Edición: | s.l. MDPI. 2021. |
| Pág./Vol.: | 11p. |
| Unidad técnica: | INTI-Mecánica. |
| Descriptores: | Biosensores; Métodos electroquímicos; Impresiones; Tintas; Nanotubos de carbono; Nanopartículas; Silicio |
| Resumen: | Railway spike screws are manufactured by hot forging on a massive scale, due to each kilometer of railway track needing 8600 spike screws. These components have a low market value, so the head must be formed in a single die stroke. The service life of the dies is directly related to the amount of energy required to form a single screw. The existing standard for spike screws specifies only the required tolerances for the head dimensions, particularly the angle of the hub faces and the radius of agreement of the hub with the cap. Both geometrical variables of the head and process conditions (as-received material diameter and flash thickness) are critical parameters in spike production. This work focuses on minimizing the energy required for forming the head of a railway spike screw by computational simulation. The variables with the highest degree of incidence on the energy, forging load, and filling of the die are ordered statistically. The results show that flash thickness is the variable with the most significant influence on forming energy and forming load, as well as on die filling. Specifically, the minimum forming energy was obtained for combining of a hub wall angle of 1.3◦ an as-received material diameter of 23.54 mm and a flash thickness of 2.25 mm. Flash thickness generates a lack of filling at the top vertices of the hub, although this defect does not affect the functionality of the part or its serviceability. Finally, the wear is mainly concentrated on the die splice radii, where the highest contact pressure is concentrated according to the computational simulation results. |
 Ver Documento
| |
Trabajo de INTI |
|
URL: |
https://www.mdpi.com/2075-4701/11/11/1834/ |
| Tipo de Docum.: | artículo |
| Título: | Sliding abrasive wear when combining WEDM conditions and polishing treatment on H13 disks over 1045 carbon steel pins |
| Autor: | Sánchez Egea, Antonio J.; Martynenko, Vitaliy; Simoncelli, Alejandro; Serrancoli, Gil; Martínez Krahmer, Daniel |
| Título Ser./Col.: | The International Journal of Advanced Manufacturing Technology, 116(5-6) |
| Idioma: | eng |
| Datos de Edición: | s.l. Springer. 2021. |
| Pág./Vol.: | 11p. |
| Unidad técnica: | INTI-Mecánica. |
| Descriptores: | Superficies; Latón; Aceros; Nitruración; Nitrógeno; Plasma; Calidad; Desgaste; Fricción |
| Resumen: | Forging dies are crucial in forging to manufacture accurate workpieces. These dies are generally made of AISI H steel series and hardened and tempered medium carbon alloy steel. Dies are processed by using high-speed milling + polishing or electrical discharge machining + polishing. The surface quality of the workpiece depends on the surface properties of these dies, where surface roughness, material hardness, and wear evolution of their surfaces are critical aspects to consider. This research analyzes different wire electrical discharge machining surface conditions combined with polishing treatment to describe their influence on friction and wear. Wire electrical discharge machining defines the disks’ surface properties in finishing and roughing conditions, and polishing treatment varies in time and paper sand depending on the roughness. Abbott-Firestone curves and Rsk-Rku roughness parameters characterize the surface roughness of each studied configuration. Room temperature pin-on-disk tests were performed to analyze friction coefficients and wear rate for AISI 1045 pins and AISI H13 disks. On average, the highest (0.284) and the lowest (0.201) friction coefficients were found for the combination of finishing wire electrical discharge machining + polishing and roughing wire electrical discharge machining conditions, respectively. Scanning electron microscope images were taken to describe the wear tracks and pin degradation for different sliding abrasive configurations. The diagram correlating the surface morphology and the friction coefficient predicts the wear damage on initial surface conditions, which is crucial in the forging industry to determine tool maintenance or replacement. |
| Ver Documento
| |
Trabajo de INTI |
|
URL: |
https://link.springer.com/article/10.1007%2Fs00170-021-07897-4 |
Fin
[Página de Inicio] [Nueva Búsqueda][Página Anterior]