Showing papers by "Maria Beatriz Silva published in 2018"
01 Aug 2018
TL;DR: In this paper, a new combined experimental and theoretical methodology for determining the formability limits by wrinkling in sheet metal forming is presented, based on the utilization of rectangular test specimens clamped along its narrower sides and compressed lengthwise.
Abstract: This paper presents a new combined experimental and theoretical methodology for determining the formability limits by wrinkling in sheet metal forming. The methodology is based on the utilization of rectangular test specimens clamped along its narrower sides and compressed lengthwise and is aimed at replicating the physics behind the occurrence of wrinkling in deformation regions submitted to in-plane compression along one direction. The methodology draws from a previous development in the field of flexible roll forming, and the overall objectives are to enhance and improve its methods and procedures and to provide a new level of understanding on the onset of wrinkling in sheet metal forming. Experimentation and finite element modelling of cylindrical deep-drawing without blank holder combined with the utilization of the space of effective strain vs. stress triaxiality are employed to discuss the applicability and validity of the new proposed methodology for determining the formability limits by wrinkling.
19 citations
TL;DR: In this paper, the formability limits by fracture obtained from standard bulk metal forming tests performed with cylindrical, tapered and flanged specimens were investigated and a total of two novel feature features were proposed.
Abstract: This article is focused on the formability limits by fracture obtained from standard bulk metal forming tests performed with cylindrical, tapered and flanged specimens. A total of two novel feature...
10 citations
29 Aug 2018
TL;DR: In this article, the authors investigate material flow and force requirement in sheet-bulk forming processes where loading is applied perpendicular to sheet thickness, and demonstrate the potential of the process to fabricate small batches of complicate parts widely used in machines and mechanisms.
Abstract: The main objective of this paper is to investigate material flow and force requirement in sheet-bulk forming processes where loading is applied perpendicular to sheet thickness. The presentation draws from material characterization to experimental and numerical analysis of process parameters related to the material and geometry of the blanks, and to the shape of the forming punches. The work is performed in aluminum AA-5754-H111 and polycarbonate and is a step towards exploring the potential of using sheet-bulk forming to produce polymer parts at room temperature. Incremental sheet-bulk forming of polymer rack gears demonstrate the potential of the process to fabricate small batches of complicate parts widely used in machines and mechanisms.