LAP SHEAR TEST OF A MAGNESIUM FRICTION SPOT JOINT: NUMERIC MODELING
ENSAIO DE CISALHAMENTO EM UMA JUNTA POR FRICÇÃO POR PONTO DE MAGNÉSIO: MODELAGEM NUMÉRICA
Campanelli, Leonardo Contri; Antonialli, Armando Ítalo S.; Alcântara, Nelson Guedes de; Bolfarini, Claudemiro; Suhuddin, Uceu Faud H.; Santos, Jorge Fernandez dos
http://dx.doi.org/10.4322/tmm.2013.014
Tecnol. Metal. Mater. Min., vol.10, n2, p.97-102, 2013
Abstract
Friction spot welding (FSpW) is one of the most recently developed solid state joining technologies. In this work, based on former publications, a computer aided draft and engineering resource is used to model a FSpW joint on AZ31 magnesium alloy sheets and subsequently submit the assembly to a typical shear test loading, using a linear elastic model, in order to conceive mechanical tests results. Finite element analysis shows that the plastic flow is concentrated on the welded zone periphery where yield strength is reached. It is supposed that "through the weld" and "circumferential pull-out" variants should be the main failure behaviors, although mechanical testing may provide other types of fracture due to metallurgical features.
Keywords
Friction welding, Magnesium, Finite element, Shear test
Resumo
A soldagem por fricção por ponto (FSpW) é uma das tecnologias desenvolvidas mais recentemente no que se refere à união no estado sólido. Neste trabalho, com base em publicações anteriores, é utilizado um recurso computacional de desenho e projeto para modelar uma junta por FSpW em chapas de liga de magnésio AZ31 e, posteriormente, submeter o conjunto a uma carga de cisalhamento típica, usando um modelo elástico linear, a fim de compreender os resultados dos ensaios mecânicos. A análise por elementos finitos mostra que o escoamento plástico concentra-se na periferia da zona soldada onde a tensão limite de escoamento é atingida. Presume-se que as variantes “através da solda” e “arrancamento circunferencial” sejam os principais modos de falha, ainda que os ensaios mecânicos venham a apresentar outros tipos de fratura em razão de fatores metalúrgicos.
Palavras-chave
Soldagem por fricção, Magnésio, Elementos finitos, Ensaio de cisalhamento
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