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The present study proposed a rapid method, based on a previous universal compression tests, to estimate the required load capacity to cold forge different specimen quantity in a screw press. Accordingly, experimental and theoretical approach are performed to check new adjustable drive motor of the modified forging machine to achieve a gross available energy to deform the specimens preventing damage of the forging machine. During the forging experiments, two screw friction presses (as-received and modified) are used to validate the theoretical approach. The modified press exhibits an increase of 51% of gross energy and 11% of maximum load capacity compare to the as-received press. This method is used to improve the effective of the forging process avoiding excessive loads that could promote machine failure. Therefore, a low-cost and easy to implement methodology is proposed to determine the energy and load capacity of a screw friction press to forge different specimen quantities with symmetry pattern configurations.

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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.

Automotive car companies are using AHSS (advanced high strength steels) over the last 20 years, to reduce vehicle weight and improve safety. The new steels can achieve higher strength and good fatigue resistance, but some issues related to springback and low formability are also a big concern. Thus, companies need to extend their know-how regarding material behaviour, design rules and manufacturing processes. Therefore, materials characterization laboratories are working to obtain the new formability charts of the steels. The grid laser marking of test pieces is a recent approach. However, the marking process must accomplish three main aspects: indelibility during the tensile testing procedure, precision, and of course, it must not affect the mechanical properties of studied steels. This work is focused on the laser marking of test pieces, using Ytterbium fiber laser. A dual phase steel (JFE CA 1180) is studied. Process parameter are defined. Keywords: grid marking, laser, advanced high-strength steels, AHSS, formability diagrams, mechanical properties

RESUMENEn la actualidad, la utilización de softwares de simulación computacional aplicados a distintos procesos de conformado, como puede ser el estampado y sus variantes, forma parte habitual de las actividades de desarrollo de las grandes industrias, y también comienzan a introducirse lentamente dentro de las PyMEs. Una de sus principales ventajas radica en la reducción significativa de los costos de desarrollo al afrontar nuevos proyectos, tanto de nuevos productos como de procesos. Asimismo, estas herramientas son ampliamente usadas para reproducir fenómenos físicos complejos. Durante un proceso de embutido (estampado profundo de chapas), el material es fuertemente solicitado, razón por la cual se requiere de un conocimiento preciso de las propiedades del mismo, como ser la ductilidad, resistencia mecánica y plasticidad. Es por ello que, se realizan ensayos de caracterización, como puede ser el ensayo Erichsen, durante el cual se recrea de manera controlada un proceso de estirado. En el presente trabajo, se efectuó la simulación de un ensayo de embutibilidad empleando el software Simufact.Forming, aplicado a una chapa de acero DC06-base IF de 0,7 mm de espesor nominal. Durante la simulación se consideraron las condiciones de lubricación, la presión del prensachapa, las dimensiones de las matrices y el coeficiente de rozamiento. Al mismo tiempo, se efectuó el ensayo experimental, con el objetivo de comparar los resultados obtenidos y validar los resultados simulados. Finalmente, se compararon las cargas de embutido, las geometrías de las copas, y el perfil de espesores resultantes en una sección diametral de la misma. Palabras Clave: Ensayo Erichsen, estampado profundo, simulación, chapa. ABSTRACTNowadays, the use of computer simulation on forming processes as stamping and its variants, is an habitual development activity of big industries, and also it is slowly being introduced in SME (Small and Mediumsize Enterprise). One of the main advantages of it is application lies-in the reduction of costs regarding new projects, products and processes developments. Likewise, these tools are widely used to reproduce complex physical phenomena. During the deep drawing process, the material is mechanically stressed, therefore requires knowledge of it is properties, such as ductility, mechanical strength and plasticity. Thus, characterization tests like the Erichsen test are performed to recreate a controlled deep drawing process. In this paper, using the Simufact.Forming software, a deep drawing test was simulated, for a steel sheet DC06 IF-base, of nominal thickness 0.7mm. During the simulation is taken into account the conditions of lubrication, pressure of blank holder, dimensions of the dies and friction coefficient. At the same time, the