A 3D reconstruction has been performed on a flat specimen after an interrupted in-situ tensile tests. The sample consisted of austempered ductile cast iron (ADI) alloyed with 2.75% nickel. The analysis was performed by using a dual beam system (FIB-SEM).
The procedure of this analysis consisted in studying the elastic-plastic behaviour along with the nucleation and the growing of cracks in ADI at room temperature. For this purpose, a field emission scanning electron microscope (FE-SEM) equipped with a tensile stage was used.
A systematic observation at the same location on the sample surface was used to clarify the tensile curves which are in agreement with deformation mechanisms. During the testing, decohesion of graphite nodules from the matrix was observed. The cracks initiated mainly at the interface of graphite nodule and the austenitic matrix. The elastic-plastic region is connected with the plastic deformation of the matrix, growth and linking of microscopic cracks which are connected and finally leading to fracture of the sample.
Figures:
Fracture of ADI after in-situ tensile test
To cite this abstract:
Hana Tesařová, Jiří Dluhoš, Martin Petrenec, Jaroslav Polák, Karel Krahula; 3D Reconstruction of Crack Formation in Austempered Ductile Cast Iron after an In-situ Tensile Test. The 16th European Microscopy Congress, Lyon, France. https://emc-proceedings.com/abstract/3d-reconstruction-of-crack-formation-in-austempered-ductile-cast-iron-after-an-in-situ-tensile-test/. Accessed: July 13, 2020« Back to The 16th European Microscopy Congress 2016
EMC Abstracts - https://emc-proceedings.com/abstract/3d-reconstruction-of-crack-formation-in-austempered-ductile-cast-iron-after-an-in-situ-tensile-test/