Institute of Physics of Materials AS CR, v. v. i. > Projects > Fatigue damage mechanisms in ultrafine grained stainless steels

Fatigue damage mechanisms in ultrafine grained stainless steels

InvestigatorIng. Jiří Man, Ph.D.
Number of Project13-32665S
AgencyGrantová agentura České republiky
Duration2013-01-31 - 2016-01-30

Anotace
Ultrafine grain austenitic stainless steel produced by transformation to martensite and reversion annealing represents an advanced material with number of possible applications. Its monotonic and fatigue properties are studied in order to characterize the material and to reveal basic damaging mechanisms contributing to the shortening of its fatigue life. Cyclic stress-strain response, internal structure of the material and its changes during cyclic loading, surface relief formation, fatigue crack initiation, short and long crack growth are studied in symmetric push-pull loading using computer controlled electrohydraulic testing system and advanced techniques as TEM, FEG-SEM, FIB, EBSD, AFM etc. The mechanisms of damage in individual stages of fatigue life are analyzed with the aim to assess the role of grain boundaries and compare the behaviour of ultrafine materials with their standard polycrystalline counterparts. The inflicted damage will be interpreted in terms of recent fatigue damage models.


2018

Man J., Järvenpää A., Jaskari M., Kuběna I., Fintová S., Chlupová A., Karjalainen L., Polák J.: Cyclic deformation behaviour and stability of grain-refined 301LN austenitic stainless structure. MATEC Web Conf. 165 (2018) 06005



2017

Man J., Smaga M., Kuběna I., Eifler D., Polák J.: Effect of metallurgical variables on the austenite stability in fatigued AISI 304 type steels. Eng. Fract. Mech. 185 (2017) 139-159

Järvenpää A., Jaskari M., Man J., Karjalainen L.: Stability of grain-refined reversed structures in a 301LN austenitic stainless steel under cyclic loading. Mater. Sci. Eng. A 703 (2017) 280-292



2016

Man J., Kuběna I., Smaga M., Man O., Järvenpää A., Weidner A., Chlup Z., Polák J.: Microstructural changes during deformation of AISI 300 grade austenitic stainless steels: Impact of chemical heterogeneity. Procedia Struct. Integr. 2 (2016) 2299-2306

Polák J., Man J.: Experimental evidence and physical models of fatigue crack initiation. Int. J. Fatigue 91 (2016) 294-303

Polák J., Mazánová V., Kuběna I., Heczko M., Man J.: Surface Relief and Internal Structure in Fatigued Stainless Sanicro 25 Steel. Metall. Mater. Trans. A 47A (2016) 1907-1911



2015

Polák J., Man J.: Quantitative model of the surface relief formation in cyclic straining. Acta Phys. Pol. A 128 (2015) 675-680

Polák J., Man J.: Initiation of stage I fatigue cracks - experiments and models. Procedia Eng. 101 (2015) 386-394



2014

Man J., Valtr M., Kuběna I., Petrenec M., Obrtlík K., Polák J.: AFM and FIB study of cyclic strain localization and surface relief evolution in fatigued f.c.c. polycrystals. Adv. Mater. Res. 891-892 (2014) 524-529

Chlupová A., Man J., Kuběna I., Polák J., Karjalainen L.: LCF behaviour of ultrafine grained 301LN stainless steel. Proc. Eng. 74 (2014) 147-150