Effect of Mo:W ratio on segregation behavior and creep strength of nickel-based single crystal superalloys

Effect of Microsegregation and Heat Treatment on Localised Γ and Γ’ Compositions in Single Crystal Ni-Based Superalloys

“…Importantly these results show that some segregation was still evident within the alloy after solutionizing and primary ageing as measured by EDX and APT. This has also been recorded within the literature with the final extent of partitioning heavily influenced by heat treatment specifications [12,13].…”

“…Despite post-solidification heat treatments designed to homogenise the alloy, a degree of segregation persists leading to chemical heterogeneity between the dendrites and interdendritic regions, which cannot be fully eliminated due to the impractical treatment times and costs required [10]. Previous studies employing EDX and EPMA have convincingly shown Re, Co and W segregating into the dendrite cores (DCs) and Al, Ti and Ta enriching interdendritic regions (IDRs), with the partitioning extent decreasing with progressively longer and hotter heat treatments [11][12][13]. Although element partitioning behaviour has been extensively mapped on the micrometre scale between DCs and IDRs, to date, fewer studies have attempted to measure the extent of segregation on the nanoscale and its subsequent effects on the local compositions of γ and γ'.…”

Possibility and stabilizing effect of Mo clusters in the Ni-based single-crystal superalloy

“…They play roles in stabilizing the alloy structure, increasing the volume fraction of γ′ phase, strengthening γ and γ′ phases, inhibiting the precipitation of harmful phases, and resisting oxidation [9][10][11][12][13]. Adding Mo will cause the local lattice distortion of the γ phase, generating a large stress field and hindering the movement of dislocations, thereby achieving a solid solutionstrengthening effect [14][15][16][17]. The Ru element can suppress the precipitation of harmful phases in the matrix, reducing the occurrence of cracks and thereby improving the high-temperature structural stability of the alloy [18][19][20][21].…”

Effect of Ta on solidification characteristics and mechanical properties of DZ411 Ni-based superalloy

“…It is of critical importance to improve the high temperature strength of directionally solidified columnar Ni-based superalloy. According to the development experience of aero-engine blades, optimizing the microstructure of alloys by adding refractory elements (Mo, W, Re, Ta) would be effective in improving the hightemperature strength of alloys for IGTs [6][7][8] .…”