Institute of Physics of Materials AS CR, v. v. i. > Projects > Effect of asymmetrical cyclic loading on early damage stadia of structural materials

Effect of asymmetrical cyclic loading on early damage stadia of structural materials

InvestigatorIng. Jiří Man, Ph.D.
Number of Project106/00/D055
AgencyGrantová agentura České republiky
Duration2000-08-31 - 2003-08-30

The project was focused on understanding of cycle asymmetry effect on early fatigue damage stages in structural materials (316L austenitic stainless steel, nickel base superalloy). Attention was paid to the study of mean stress effect on surface relief accompanying fatigue crack initiation. Surface relief was studied using high-resolution microscopy techniques – SEM and AFM. The experimental characteristics concerning to the slip activity in individual grains, to the surface relief evolution in dependence on applied loading conditions (plastic strain amplitude, mean stress value) and on the number of cycles were determined. Experimental results obtained were analysed and quantified in terms of the static and cyclic contributions.


Man J., Petrenec M., Obrtlík K., Polák J.: AFM and TEM study of cyclic slip localization in fatigued ferritic X10CrAl24 stainless steel. Acta Mater. 52 (2004) 5551-5561


Polák J., Man J., Obrtlík K., Kruml T.: The shape of extrusions and intrusions produced by cyclic straining. Z. Metallkd. 94 (2003) 1327-1330

Man J., Obrtlík K., Polák J.: Study of surface relief evolution in fatigued 316L austenitic stainless steel by AFM. Mater. Sci. Eng. A 351 (2003) 123-132

Polák J., Man J., Obrtlík K.: AFM evidence of surface relief formation and models of fatigue crack nucleation. Int. J. Fatigue 25 (2003) 1027-1036


Man J., Obrtlík K., Blochwitz C., Polák J.: Atomic force microscopy of surface relief in individual grains of fatigued 316L austenitic stainless steel. Acta Mater. 50 (2002) 3767-3780