Systematic fatigue experiments, including both high-cycle axial fatigue (S-N curves) and fatigue crack growth (FCG, da/dN-ΔK curves), were performed on a precipitation-hardening martensitic stainless steel in laboratory air and 3.5 wt% NaCl solution. Specimens were prepared in three tempers, i.e. solution-annealed (SA), peak-aged (H900) and overaged (H1150) conditions, to characterize the effects of ageing treatment on the corrosion fatigue (CF) resistance. S-N results indicated that fatigue resistance in all three tempers was dramatically reduced by the aqueous sodium chloride environment. In addition, the smooth-surface specimens in H900 temper exhibited longer CF lives than the H1150 ones, while those in SA condition stood in between. However, for precracked specimens, the H1150 temper provided superior corrosive FCG resistance than the other two tempers. Comparison of the S-N and FCG curves indicated that early growth of crack-like defects and short cracks played the major role in determining the CF life for smooth surface. The differences in the CF strengths for the S-N specimens of the given three tempers were primarily due to their inherent differences in resistance to small crack growth, as they were in the air environment.
|Number of pages||9|
|Journal||Fatigue and Fracture of Engineering Materials and Structures|
|State||Published - 2000|