Definition of the linearity loss of the surface temperature in static tensile tests
Journal Title: Frattura ed Integrità Strutturale - Year 2014, Vol 8, Issue 30
Abstract
Static tensile tests on material for mechanical constructions have pointed out the linearity loss of the surface temperature with the application of load. This phenomenon is due to the heat generation caused by the local microplasticizations which carry the material to deviate from its completely thermoelastic behavior,. The identification of the static load which determines the loss of linearity of the temperature under stress, becomes extremely important to define a first dynamic characterization of the material. The temperature variations that can be recorded during the static test are often very limited (a few tenths of degree for every 100 MPa in steels) and they require the use of special sensors able to measure very low temperature variations. The experience acquired in such analysis highlighted that, dealing with highly accurate sensors or with particular materials, the identification of the first linearity loss (often by eye) in the temperature curves, can be influenced by the sensibility of the investigator himself and can lead to incorrect estimates. The aim of this work is to validate the above mentioned observations on different steels, by applying the autocorrelation function to the data collected during the application of a static load. This, in order to make the results of the thermal analysis free from the sensitivity of the operator and to make the results as objective as possible, for defining the closest time of the linearity loss in the temperature-time function.
Authors and Affiliations
A. Risitano, G. Fargione, E. Guglielmino
Keywords
Related Articles
- EP ID EP126869
- DOI -
- Views 70
- Downloads 0
Welding sequence effects on residual stress distribution in offshore wind monopile structures
Residual stresses are often inevitably introduced into the material during the fabrication processes, such as welding, and are known to have significant effects on the subsequent fatigue crack growth behavior of&n...
Estimation of fretting fatigue life using a multiaxial stress-based critical distance methodology
This work presents a methodology for life estimation of mechanical couplings subjected to fretting fatigue. In this approach, a stress-based multiaxial fatigue parameter is evaluated at a critical distance below t...
The effect of steady torsion on fatigue crack growth under rotating bending loading on aluminium alloy 7075-T6
Axles and shafts are of prime importance concerning safety in the transportation industry and railway in particular. Design rules for axles and shafts are mainly based on endurance curves for the material used ac...
Numerical simulation of early-age shrinkage effects on RC member deflections and cracking development
Shrinkage effects on short-term behavior of reinforced concrete elements are often neglected both in design code provisions and in numerical simulations. However, it is known that their influence on serviceabilit...
The application of the infrared thermography on titanium alloy for studying fatigue behavior
The infrared thermography is an attractive tool for studying the fatigue behavior of materials. Based on two theoretical models of fatigue damage indicators, this work studied the fatigue properties of the virgin T...