Tensile properties of mechanically alloyed oxide dispersion strengthened iron alloys Part 2 – Physical interpretation of yield strength

AbstractThe components of the yield strength of MA956, a mechanically alloyed oxide dispersion strengthened iron base superalloy, have been investigated quantitatively. It is found that much of the difference in strength between the recrystallised and unrecrystallised forms can be explained in terms of the grain structure. The contribution from dispersion strengthening has been estimated using dislocation theory and has been demonstrated to be consistent with that measured experimentally. The temperature dependence of the yield strength has also been studied; some of the effects observed in the range 500–600°C can be attributed to the change in the intrinsic strength of pure annealed iron.