Publication detail

Low cycle fatigue of austempered ductile cast iron alloyed with nickel at room and at depressed temperature

PETRENEC, M. BERAN, P. ŠMÍD, M. ROUPCOVÁ, P. TESAŘOVÁ, H.

Czech title

Nízko-cyklová únava ADI litiny legované niklem při pokojové a snížené teplotě

English title

Low cycle fatigue of austempered ductile cast iron alloyed with nickel at room and at depressed temperature

Type

journal article - other

Language

en

Original abstract

Total strain controlled tests have been performed on cylindrical specimens of austempered ductile cast iron (ADI) with the aim to compare cyclic plasticity and the fatigue life at temperatures 23 C and – 45 C. Microstructure and its quantities are documented using light microscope (image analysis) and neutron diffraction. The measurement of retained austenite by neutron diffraction before and after fatigue tests is used to discuss the cyclic stress-strain response. Cyclic hardening/softening curves, cyclic stress-strain curves and fatigue life curves were obtained for both temperatures. Cyclic stress-strain curve obtained at -45 C is shifted to higher stress amplitudes relative to room temperature curve. The fatigue life curves at both temperatures can be well approximated by the Manson-Coffin and Basquin laws. The Manson-Coffin curves are identical at both temperatures while the Basquin curve is shifted to longer fatigue life. The surface relief developed during fatigue was studied using SEM. Fatigue cracks initiated preferably from persistent slip markings at the interface of graphite nodule and the ausferrite matrix.

Czech abstract

Na válcových zkušebních tyčích z ADI litiny byly provedeny únavové zkoušky v režimu řízení celkové deformace za cílem porovnat cyklickou plasticitu a únavový život při teplotách 23 C a – 45 C. Mikrostruktura byla zdokumentovaná pomocí světelné mikroskopie ( obrazová analyza ) a neutronové difrakce. Neutronová difrakce byla použita za účelem změření množství zbytkového austenitu před a po únavové zkoušce a k vysvětlení napěťové-deformační odezvy experimentálního materiálu. Při obou teplotách byly získány křivky cyklického zpevnění/změkčení, cyklické deformační křivky a křivky únavové životnosti. Povrchový reliéf, jenž vznikl po cyklickém zatěžování byl studován s použitím SEM. Únavové trhliny vznikaly především z persistentních skluzových stop na rozhraní grafitických nodulí a matrice.

English abstract

Total strain controlled tests have been performed on cylindrical specimens of austempered ductile cast iron (ADI) with the aim to compare cyclic plasticity and the fatigue life at temperatures 23 C and – 45 C. Microstructure and its quantities are documented using light microscope (image analysis) and neutron diffraction. The measurement of retained austenite by neutron diffraction before and after fatigue tests is used to discuss the cyclic stress-strain response. Cyclic hardening/softening curves, cyclic stress-strain curves and fatigue life curves were obtained for both temperatures. Cyclic stress-strain curve obtained at -45 C is shifted to higher stress amplitudes relative to room temperature curve. The fatigue life curves at both temperatures can be well approximated by the Manson-Coffin and Basquin laws. The Manson-Coffin curves are identical at both temperatures while the Basquin curve is shifted to longer fatigue life. The surface relief developed during fatigue was studied using SEM. Fatigue cracks initiated preferably from persistent slip markings at the interface of graphite nodule and the ausferrite matrix.

Keywords in Czech

ADi litina legovaná niklem, nízko cyklová únava, snížená teplota, neutronová difrakce, iniciace únavové trhliny

Keywords in English

ADI with nickel alloying, low cycle fatigue, depressed temperature, neutron diffraction, fatigue crack initiation.

RIV year

2009

Released

02.09.2009

Publisher

University of Žilina

Location

Žilina

ISSN

1335-0803

Journal

Materiálové inžinierstvo

Volume

16

Number

3a/2009

Pages from–to

1–6

Pages count

6

BIBTEX


@article{BUT49760,
  author="Martin {Petrenec} and Přemysl {Beran} and Miroslav {Šmíd} and Pavla {Roupcová} and Hana {Tesařová},
  title="Low cycle fatigue of austempered ductile cast iron alloyed with nickel at room and at depressed temperature",
  journal="Materiálové inžinierstvo",
  year="2009",
  volume="16",
  number="3a/2009",
  month="September",
  pages="1--6",
  publisher="University of Žilina",
  address="Žilina",
  issn="1335-0803"
}