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Hot deformation is one of the main technological stages of products made from metallic materials. It is strictly required to decrease the costs of developing optimized technologies at this stage without a significant decrease in the products’ quality. The present investigation offers an algorithm to unite three different models to predict the hot deformation behavior, fracture, and microstructure evolution. The hot compression and tension tests of the AISI 316Ti steel were conducted using the thermomechanical simulator Gleeble 3800 for the models’ construction. The strain-compensated constitutive model and the Johnson–Mehl–Avrami–Kolmogorov (JMAK)-type model of the grain structure evolution show a satisfactory accuracy of 4.38% and 6.9%, respectively. The critical values of the modified Rice and Tracy fracture criteria were determined using the experimental values of the relative cross-section reduction and finite element calculation of the stress triaxiality. The developed models were approved for the stainless AISI 316Ti steel by the hot torsion with tension test.

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The effect of zirconium on the microstructure, phase composition, and mechanical properties of AlCuYb and AlCuGd alloys was studied. The microstructure of the as-cast alloys did not consist of new intermetallic phases of zirconium with other elements, so the zirconium was fully dissolved in the aluminum matrix. The AlCuYbZr/AlCuGdZr alloys demonstrated higher hardness values compared to the AlCuYb/AlCuGd alloys due to the precipitation of the Al3(Zr,Yb) and Al3(Zr,Gd) phases, which were formed during the homogenization treatment. The AlCuYbZr alloy had a 10-20 MPa higher yield and tensile strength than the AlCuGdZr alloy at the same annealing temperature and time. The AlCuYbZr alloy exhibited good mechanical tensile properties at an annealing temperature of 100 °C for 1h, with a yield strength of 276 MPa, ultimate tensile strength of 312 MPa, and elongation of 3.1%, while the as-rolled AlCuGdZr alloy had similar mechanical tensile properties, with a yield strength of 279 MPa, ultimate tensile strength of 307 MPa, and elongation of 4.8%. At an annealing temperature of 300 °C for 10 min, The AlCuYbZr and AlCuGdZr alloys showed a good ductility of 10.5% and 8%, respectively, with 207 MPa yield strength for both alloys. AlCuYbZr and AlCuGdZr alloys are a prospective base composition for developing novel high technology heat resistant aluminum alloys.

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