Volume 6, Issue 1 (January 2009)
An Expert System for Estimation of Fatigue Properties from Simple Tensile Data or Hardness
Fatigue properties such as strain-life (ε-N) curves are usually obtained by performing fatigue tests. However, as fatigue testing requires time and high cost, many methods have been proposed to estimate the strain-life curves from simple tensile data or hardness. Based on results of recent studies, an expert system is developed to estimate with high accuracy fatigue properties (strain-life curves) from simple tensile data or hardness. The expert system is developed by using a commercial expert system shell, Acquire. The expert system consists of two modules, Fatigue Properties Estimation module and Knowledge Base Update module. An important feature of the expert system is to provide results of fatigue properties estimation with information of their anticipated accuracy. The fatigue data used for the performance testing of the expert system are 96 ε-N curves consisting of 663 ε-N data points obtained for 52 materials. The expert system has very good performance for steels, aluminum alloys, and titanium alloys, even when only hardness data are available as well as when simple tensile data are available.