On a new temperature factor to predict the fatigue limit at different temperatures

This study is concerned with a non-conventional fatigue strength behavior of some materials with temperature. Notwithstanding the common reduction on fatigue limit of most materials with temperature, some materials show a non-conventional behavior, e.g., a temperature change from 20 degrees C to about 300 degrees C or 400 degrees C cause an increase in fatigue limit and/or tensile strength. The change in fatigue limit and tensile strength may have opposite trends. The existing 'temperature effect' parameters used in fatigue limit equations do not properly incorporate this non-conventional behavior. This study will propose a temperature factor that is able to properly incorporate the non-conventional behavior of some materials. It will also be shown that the new proposed temperature factor may be applied also to conventional materials with improved accuracy being than a more universal temperature factor. (c) 2010 Elsevier Ltd. All rights reserved.