Análise do comportamento em fluência de juntas metálicas coladas

Abstract

Numerous advantages presented by the use of adhesive bonded joints have been noted, leading to an increase use of this type of joining of materials in place of traditional methods. Despite this growth, little information is found in the literature on the behavior of these unions under creep, due to the high execution time of these tests when compared with other destructive tests. With the aid of the Creep Pneumatic Equipment (CPE) created by the Adhesion and Adherence Laboratory (AAL / UERJ / IPRJ), tests were performed with variation in percentages of rupture stress, and this machine can test up to 10 specimens per turn. The creep behavior analysis of single lap joints (SLJ) composed of metallic substrates and glued with an epoxy base adhesive (NVT 201E®) and another based on polyurethane (Masterpur Structural 300®) were performed. After the analyzes, it was possible to compare them with previous creep tests performed in the AAL with joints with epoxy base adhesives (Multi-metall®) and polyurethane (Fusor®). It was concluded that creep rupture stresses for the tests exceeding 1000 hours of the bonded joints with both epoxy base adhesives was similar. The creep behavior of the bonded joints with the polyurethane based adhesives differed widely. The fractures presented after the fluence tests of the joints bonded to the NVT 201E® were mixed (cohesive and adhesive) and the joints bonded with the Masterpur Structural 300® were predominantly adhesive. Some considerations were made in finite element analysis software, Abaqus®, to simulate the creep tests performed. To find the creep parameters, it is necessary to obtain the adhesive creep curve, which has not been obtained in this dissertation. Therefore, creep parameters of another epoxy based adhesive and properties similar to those of NVT 201E® were considered in order to show the steps required for creep modeling in Abaqus.