Intermetallic compounds Cr3Te4/NiNbTe2 formation during infiltrating Te into Inconel 718

The reason for Te damage to nickel-based superalloy during its service process in the detrimental environment has been widely focused on. Nevertheless, the surface crack sprouting and material failure caused by Te have not been well addressed. Direct evidence is still lacked to support the underlying explanation of Te damage to nickelbased superalloys. In this research, innovative solid-state infiltration of Te is employed to demonstrate the mechanism of Te damage to Inconel 718. Different Te infiltration temperatures result in varied intermetallic compounds. Significant Cr depletion occurs in the vicinity of the new intermetallic compounds. The weakening effect of the new intermetallic compounds relative to grain boundaries is triple, including its own low hardness, low density and large volume leading to grain boundary expansion. This paper contributes to a deeper understanding of the mechanism of Te damage to Inconel 718 and can provide ideas for the prevention of material failure.

Automated summary

This study demonstrates the mechanism of Te damage to Inconel 718 through innovative solid-state infiltration of Te, showing that different Te infiltration temperatures result in varied intermetallic compounds. The weakening effect of the new intermetallic compounds relative to grain boundaries is triple, including its own low hardness, low density and large volume leading to grain boundary expansion.