EFEITO DA ESPESSURA DO ADESIVO NO COMPORTAMENTO MECÂNICO DE JUNTAS ADESIVAS PARA APLICAÇÃO AUTOMOTIVA
EFFECT OF ADHESIVE THICKNESS IN THE MECHANICAL BEHAVIOR OF ADHESIVE JOINTS FOR AUTOMOTIVE APPLICATIONS
Diego Tolotti de Almeida João Henrique Corrêa de Souza Piero David Maehler Tiago Roberto Simon
Resumo
É crescente a aplicação de adesivos estruturais como método de fixação nos diversos segmentos da indústria, principalmente na indústria automotiva. Isso se justifica pela necessidade de redução do consumo de energia e economia de recursos, trazendo assim, uma série de benefícios ao produto/processo, quando comparado aos tradicionais sistemas de fixação com parafuso, rebite ou solda. Esta pesquisa estudou alguns fatores que influenciam nas forças mecânicas das juntas adesivas submetidas ao ensaio de tração cisalhante (Lap Shear) e tração cruzada (Cross Peel). Três diferentes espessuras do adesivo foram utilizadas para fabricar as juntas adesivas (0,80, 1,50 e 3,00mm). Além disso, foi possível identificar o efeito de diferentes materiais de base sobre o comportamento mecânico das juntas adesivas. Resultados experimentais mostraram que menores espessuras de adesivo aumentam consideravelmente a resistência mecânica das juntas submetidas a ensaio de tração cisalhante. Por outro lado, resultados obtidos no ensaio de tração cruzada, não apresentaram este mesmo comportamento. No entanto, existe uma relação entre a performance da junta e o material do substrato a ser colado.
Palavras-chave
Abstract
The application of structural adhesives is increasing as a method of fixation in the various segments of industry, especially in the automotive industry. This is justified by the need to reduce energy consumption and save resources, thus bringing a series of benefits to the product / process compared to traditional fastening systems with bolt, rivet or weld. This study studied some factors that influence the mechanical strength of the adhesive shear tests submitted to the Lap Shear and Cross Peel tests. Three different adhesive thicknesses were used to make the adhesive joints (0.80, 1.50 and 3.00mm). In addition, it was possible to identify the effect of different base materials on the mechanical behavior of the adhesive joints. Experimental results have shown that minor adhesive thicknesses considerably increase the mechanical strength of the joints subjected to shear traction tests. On the other hand, the results of the cross-traction test did not obtain this same behavior. However, there is a relationship between the performance of the joint and the material of the substrate to be bonded.
Keywords
Referências
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