23 research outputs found
Structural changes in metastable austenitic steel during equal channel angular pressing and subsequent cyclic deformation
The paper reports a substantial improvement of the static and cyclic strength of a Cr-Ni-Ti austenitic stainless steel nanostructured by equal channel angular pressing (ECAP). After ECAP at room temperature or 673 K, the mean grain size decreased from 14 µm to 430 nm or 940 nm, respectively; corresponding ultimate tensile strength increased from 610 MPa to 1230 MPa or 940 MPa, and the fatigue limit increased from 275 MPa to 375 MPa or 475 MP
Thermodynamic Evaluations of the Al-Li-Cu-Mg-Zr Systems
The investigation of the AlLiCuMgZr system is accomplished in this report. Theevaluations of the CuMgZr and CuLiMg systems and the experimental study of theAlLiCuMg system were carried out during the COST 507 second round.The evaluation of the CuLiMg system was based on the DSC experiments at thelarge range of composition. The parameters of the excess Gibbs energy obtainedagreed quite well with the temperatures of the phase transformations but the fit wasnot so good using the experimental enthalpies. The decomposition temperature of the phase was fixed at 702.7 and was not defined earlier in the literature.The optimisation of the CuMgZr system was based on the experimental data fromthe literature and on one set of the DTA experiments measured. The calculated phasediagram was in good agreement with the data used. The existence of the new phaseas well as the parameters of formation of the excess Gibbs energy contributed well thesystem studied.The phase relations near to Alrich corner containing up to 7 wt.% Li, 7 wt.% Mg and10 wt.% Cu were investigated using microscopy analysis, quality local Xray spectralanalysis and Xray phase analysis in the experimental study of the AlLiCuMgsystem done by Baikov Institute of Metallurgy