Application of small punch test to investigate mechanical behaviours and deformation characteristics of Incoloy800H

In this study, mechanical behaviours and deformation characteristics of Incoloy800H were investigated experimentally and analytically by small punch test at various temperatures. First, parameter sensitivity analysis was performed in order to estimate the influence of anisotropy, geometric dimensions, and temperature on material strengths. Then, the mechanical properties of Incoloy800H were investigated. A relatively simple yet reasonable relation between mechanical properties and specimen thickness was obtained. A new prediction model based on the deformation energy was established. Meanwhile, the inverse prediction model based on golden section search algorithm was proposed to estimate the yield strength and constitutive parameters on the basis of iterative calculations. On the other hand, a small punch deformation model was discussed. The hardness, strain, and stress triaxiality were analysed in order to estimate the evolution of plastic damage and deformation character. Finally, an economic, accurate mechanical behaviour evaluation system of Incoloy800H was established on the basis of the small punch test.