Rapid determination for fatigue parameters of AZ31B magnesium alloy based on evolution of temperature under high cyclic fatigue

Abstract

Based on the infrared thermography method, experiments are carried out to investigate the evolution of temperature field of the extruded AZ31B magnesium alloy specimens under high cyclic fatigue load. The experimental results show that the superficial temperature of specimen under cyclic fatigue load changes with the number of cycles. According to the characteristics of surface temperature change, we propose a formula to calculate the residual fatigue life using energy approach. The proposed formula to assess the fatigue parameters (fatigue limit, residual fatigue life, fatigue life and S–N curve) achieves good results for AZ31B magnesium alloy. Furthermore, the fatigue limits (Δ σeSN = 90·3 MPa) derived from the traditional method through 107 cycles were compared with the values predicted by the infrared thermographic method (Δ σeTM = 87·3 MPa) and the energy approach (Δ σeΦ = 86·2 MPa), and the comparison results of percentage differences are 3·3 and 4·5 respectively.

Fatigue fracture behaviour and thermographic analysis of friction stir-welded AZ31

“…In our previous work, the fatigue fracture behaviour of AZ31B magnesium alloy and its welding joints were investigated by using infrared thermographic method, including fatigue life prediction, 22 analysis of fatigue behaviour, 23 mechanism of heat generation 24 and rapid determination for fatigue parameters (fatigue limit, residual fatigue life, S-N curve). 25 However, according to the authors' knowledge, there is little study on the fatigue fracture of FSW AZ31 by infrared thermographic which was not presented in those works. Therefore, the aim of this study was to understand the fatigue fracture behaviour of FSW AZ31 and cyclic deformation behaviour of this FSW joints by infrared thermographic.…”

An energetic method to evaluate the macro and micro high-cycle fatigue behavior of the aluminum alloy

“…6–8 Fatigue thermography, based on the accurate measurements and analysis of the full field temperature signals, has attracted widespread attention during the last decades. 9–12 As a matter of fact, the fatigue damage accumulation is an energy dissipation process accompanied by the temperature variation. Therefore, the temperature-based thermography has been widely and successfully applied to predict the fatigue behavior of various materials, 13–16 such as fatigue crack initiation and propagation, 17–19 fatigue parameters and damage status analysis.…”