Rheological properties of EP742-ID alloy in the context of Integrated Computational Materials Engineering (ICME). Part 2. Modeling the compression process for samples and virtual workpieces

Abstract

The second part of this paper compares modeling and experimental results with the Huber–Mises plasticity theory during the axisymmetric settlement of EP742-ID alloy samples with various ratios of initial d0/h0 sizes. The influence of initial sizes on the strain-stress state of model experimental samples and virtual workpieces is estimated. Settlement modeling results are given for ∅15 mm cylindrical samples and ∅300 mm workpieces made of EP742-ID heat-resistant nickel alloy with various ratios of initial similar sizes with the substantiation of choosing average stress and equivalent deformation as internal factors that determine microstructure formation. It is shown that compression axial tension component values in the center of samples under initial plastic deformation of 0,2 % are increased by more than 1,5 times with the higher d0/h0 ratio. Experimental and calculated values of offset yield strength, axial and radial stresses are obtained at a compression temperature of 1050 °C depending on d0/h0. The paper reviews the influence of the degree of deformation and the ratio of initial sizes on the distribution of average stress and equivalent deformation along the radius of the mid-height of meridian sections of the ∅15 mm settled (experimental) samples and ∅300 mm virtual workpieces. The paper describes general microstructure forecasting principles for applications that use process modeling software packages when developing settlement modes for disk workpieces made of heat-resistant nickel alloys. Special attention is paid to the fact that modeling methods must be theoretically proved and experimentally confirmed.