Shock wave characterization of precipitate strengthening of PH 13–8 Mo stainless steel

Abstract The shear stresses required for dislocations passage of highly coherent NiAl-based precipitates, formed in commercial PH 13-8 Mo steel after homogenization, quenching and aging for different duration of time at 510°C, were determined in a series of planar impact experiments using samples with different thickness. The experiments revealed two regimes of decay of the elastic precursor waves: a fast one, at the shear stressτgreater than some thresholdτ*, associated with the interaction of moving dislocations with lattice phonons, and a slow one, at τ