Numerical Simulation of the Fatigue Behaviour of a Friction Stirred Channel Aluminium Alloy

¹ Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
² ESTSetúbal, Instituto Politécnico de Setúbal, Campus do IPS, Estefanilha, 2914-508 Setúbal, Portugal
³ LAETA, IDMEC, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal

^* Corresponding author: virginia.infante@tecnico.ulisboa.pt

Abstract

Friction stir channelling (FSC) is one of the most promising innovations based on the friction stir concepts. FSC uses a non-consumable tool, similar to that used to perform the friction stir welding (FSW) process, to produce continuous and integral channels, with any path, in monolithic aluminium alloys components in a single step. This paper presents the mechanical behaviour of friction stirred channel components in particular the fatigue resistance of the channels analysed. Finite element analyses were performed taking into account the maximum stress values applied in experimental fatigue tests of the aluminium components. The energy release rate for different crack lengths was obtained using the software ABAQUS. The fatigue crack growth curve was established according to the Paris Law, and the crack propagation direction was calculated using the maximum tangential stress (MTS) criterion. During the analysis it was observed that the critical areas are located in the vicinity of the channels corners, as it was observed in the fracture surfaces of the experimental fatigue test results.