Yield strength of Ni–Al–Cr superalloy under pressure

Abstract

a b s t r a c tNi based superalloy NieAleCr with g and g 0 phase was studied under high pressure up to 30 GPa using diamond anvil cell technique. In-situ X-ray diffraction data was collected on these alloys under hydrostatic and non-hydrostatic conditions. Cubic phase remains stable up to the highest pressure of about 30 GPa. Bulk modulus and its pressure derivative obtained from the volume compression of pressure data are K ¼ 166.6 ± 5.8 GPa with K 0 set to 4 under hydrostatic conditions and K ¼ 211.3 ± 4.7 GPa with K 0 set to 4 for non-hydrostatic conditions. Using lattice strain theory, maximum shear stress 't' was determined from the difference between the axial and radial stress components in the sample. The magnitude of shear stress suggests that the lower limit of compressive strength increases with pressure and shows maximum yield strength of 1.8 ± 0.3 GPa at 20 GPa. Further, we have also determined yield strength using pressure gradient method. In both the methods, yield strength increases linearly with applied pressure. The results are found to be in good agreement with each other and the literature values at ambient conditions.

Structure and properties of a composite material obtained by thermal explosion in a mixture of Ni + Al + Cr2O3

“…The properties of aluminide nickel based alloys are enhanced by modifying them with refractory metals (chromium, molybdenum, tungsten, etc.). Addition of Cr to Ni 3 Al stabilizes the γ-and γ -regions of the crystal structure and improves the ductility and corrosion properties [19]. The mechanical properties of the resulting composites are strongly influenced by the size of the introduced particles, their volume fraction in the matrix, and the uniformity of particle distribution [20].…”