Miniature Test Technique for Acquiring True Stress–Strain Curves for a Large Range of Strains Using a Tensile Test and Inverse Finite Element Method

The paper presents a non conventional technique to predict the constitutive behavior of materials by assessing the true stress–true strain relationship through miniature specimen tests. The miniature test was conducted on two different types of steel ring specimens (outer diameter14mm, inner diameter 8mm, thickeness 0.5mm) with V-notch (1mm depth) added diametrically to it. A finite element model was developed and validated to calculate the load–deflection curve obtained from the miniature specimen experiment. The constitutive behavior assigned to the specimen for the calculations was determined from the standard tensile test. Using an inverse methodology, it was possible to show that the constitutive behavior from the miniature tests using inverse FE procedure, and that from the conventional standard ASTM test bears close resemblance.