Review on the prediction of residual stress in welded steel components

Residual stress after welding has negative effects on the service life of welded steel components or structures. This work reviews three most commonly used methods for predicting residual stress, namely, empirical, semi-empirical and process simulation methods. Basic principles adopted by these methods are introduced. The features and limitations of each method are discussed as well. The empirical method is the most practical but its accuracy relies heavily on experiments. Mechanical theories are employed in the semi-empirical method, while other aspects, such as temperature variation and phase transformation, are simply ignored. The process simulation method has been widely used due to its capability of handling with large and complex components. To improve its accuracy and efficiency, several improvements need to be done for each simulation aspect of this method

Comunidades virtuales: escritores y lectores de Fanfictions de anime en el Perú

Trabajo de investigaciónLas historias de ficción compartidas en las comunidades virtuales han llamado la atención de los jóvenes internautas incitándolos a participar en ellas. Los Fanfictions son textos digitales que guardan la estructura literaria formal con factores propios de la escritura en la web, por lo tanto, albergan características textuales propias que luego son adaptadas por cada comunidad virtual. En esta investigación se analizaron las rutinas narrativas de tres plataformas virtuales, en las cuales el anime era el protagonista. Los objetos de estudio fueron la página web Fanfictions.net y aplicación móvil Wattpad, que fueron seleccionadas porque acogían el universo de investigación que nos permitió encontrar algunos elementos comunes de esta forma de expresión cultural. Este análisis nos permite adentrarnos en el Perú mediante una línea de trabajo que todavía no ha sido muy desarrollada. El aporte de esta investigación pretende generar una discusión teórica sobre un campo que es emergente en el Perú

Broad stress triaxiality ratio band fracture experiments in DP900 metal sheets and corresponding predictive capability of advanced phenomenological and micromechanical fully coupled damage models

Correct prediction of the fracture time and location and their evolution in metallic materials has always been a research hotspot in the field of metal forming. To this end, and in the context of metal forming process simulation, an advanced mathematical material model is crucial. In this paper, we investigate the accuracy of two fully-coupled damage models, one of which is phenomenologically-based and the other one micromechanically-based, in predicting the failure in DP900 steel plates subject to various loading paths. These are applied throughout tests, including tensile tests on unnotched and notched specimens with different notch radii as well as butterfly wing shear tests. Through the comparisons of the numerical and experimental results, in terms of force-displacement curves and fracture strains (or ductility) under wide range of strain paths, the accuracy of the proposed two coupled damage models are discussed