A systematic FEM analysis of the influence of mechanical properties in the reliability of the correlation methods in the small punch test

The Small Punch Test (SPT) is a miniature mechanical characterization test used as an alternative method to obtain a wide selection of mechanical properties (Young's modulus, yield strength, ultimate tensile strength, fracture toughness, etc). These mechanical properties are obtained in the SPT from correlations with different data of the load-displacement curve of the test (SPT curve). The main disadvantage of the SPT is the scattering observed when a wide set of materials is included in the correlations. A systematic finite element analysis of the SPT was performed for an extensive selection of hypothetical materials with an extensive range of mechanical properties (Young's modulus, yield strength and strain hardening) in order to study the influence of each mechanical property on the correlation methods. This investigation showed the multi-dependencies of the current correlation methods with more than one mechanical property. These multiple dependencies were analyzed and quantified and were introduced in the correlation equations to reduce the scattering.