Modified Low Cycle Method as a New Criterion for a Life Fatigue Assessment in Foundry Industry

The study describes the investigations of fatigue life carried out on selected grades of the G20Mn5 cast steel by two methods, i.e. the standard low-cycle fatigue test (LCF test) and modified low-cycle fatigue test (MLCF). The aim of these investigations was to verify the reliability of tests conducted by the novel method of MLCF [1, 2, 3]. Table 1 shows the results of mechanical tests carried out in accordance with the MLCF methodology on the G20Mn5 cast steel, while Figures 1a-b and 2 show the selected σ = f (ε) curves. Similar studies were carried out for the Mn-Ni cast steel [4]. Low-cycle fatigue tests (LCF) were carried out on an MTS 810 testing machine with control of force exerted on specimens whose dimensions were specified in [2].