Experimental and numerical assessment of the end of the thermoelastic effect during static traction test

Abstract

In the last thirty years Infrared Thermography has been widely adopted as a technique able to predict the fatigue life of materials in a short amount of time. In the recent years, Risitano and Risitano proposed the Static Thermographic Method as a rapid test procedure able to predict the fatigue limit of the material from a static traction test, evaluating the end of the thermoelastic phase. In this work, the energetic release during a uniaxial static test of a medium carbon steel C45 has been experimentally investigated. A numerical finite element model has been developed in order to predict the temperature evolution of the material under the same monotonic load conditions. A comparison between the experimental and numerical temperature evolution has been carried out showing how the end of the thermoelastic phase is reached before the macroscopic yielding stress of the material. The Static Thermographic Method may be adopted as a novel energetic approach to assess the macroscopic stress value that introduce in the material the first micro plasticization, hence will lead it to fatigue failure.