Anisotropy of the mechanical properties of nickel-base heat resistant alloys

Conclusions

• 1. The anisotropy of the mechanical properties of high-alloy heat resistant alloys is affected by two factors-chemical heterogeneity and the associated difference in the degree of hardening of axial and interaxial sections, and the heterogeneous distribution of undissolved inclusions (segregation products).

• 2. Tungsten is the most susceptible to segregation, which leads to heterogeneous decomposition of the fibrous structure after hot reduction of ingots and the standard heat treatment.

• 3. At room temperature the anisotropy of the mechanical properties is due mainly to the heterogeneous distribution of hardening phase. At solutioning temperatures the anisotropy of the ductility depends mainly on the number and distribution of nonmetallic inclusions.

• 4. The anisotropy of the mechanical properties of nickel alloys can be reduced by increasing the purity with respect to nonmetallic inclusions, which can be achieved by double vacuum remelting (VI + VAR or VAR + VAR).