Effect of а Number of Transition Metals on the Cohesive Properties of Cr-Ni-Base Alloys

We used the results of ab initio calculations to improve the high temperature mechanical properties of a Cr-Ni-base alloy (Cr-33Ni-2W-0,3Ti-0,3V, wt.%) (alloy I) with two-phase α - γ microstructure. It was established that γ – phase in Cr-Ni-base alloy (I) plays a key role in the processes of plastic deformation. By analogy with Ni-base superalloys the bulk and grain boundaries cohesion in γ – phase of the Cr-Ni-base alloy (I) were strengthened by adding a package of the “low alloying” elements (Zr, Hf, Nb, Ta) (alloy II) chosen in accordance with our theoretical predictions. We further investigated an influence of a sum (Ta, Nb, Hf, Zr) like the low alloying additions on the mechanical properties of Cr-Ni-base alloy (I). The results of mechanical testing revealed a significant strengthening of the alloy (II) in comparison with (I) at the temperature 1080 oC in accordance with our predictions. We also investigated the microstructure’s peculiarities of the alloys (I) and (II).