Fatigue crack propagation in UFG Ti grade 4 processed by severe plastic deformation

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F17%3A00471662" target="_blank" >RIV/68081723:_____/17:00471662 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.ijfatigue.2017.01.028" target="_blank" >http://dx.doi.org/10.1016/j.ijfatigue.2017.01.028</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijfatigue.2017.01.028" target="_blank" >10.1016/j.ijfatigue.2017.01.028</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Fatigue crack propagation in UFG Ti grade 4 processed by severe plastic deformation

Popis výsledku v původním jazyce

Fatigue crack growth was investigated in commercially pure Ti grade 4 processed by severe plastic deformation. The ultrafine-grained structure was prepared by means of equal channel angular pressing technique followed by cold drawing. The growth of fatigue cracks was investigated also in the as-received coarse-grained state of material for comparison.nThe fatigue crack growth rate in the ultrafine-grained material was found to be higher and the threshold stress intensity range delta Kth for crack growth lower than in the coarse-grained Ti, 2.5 and 4.7 MPa m1/2, respectively. A combination of transcrystaline and intercrystaline crack growth was typical for all crack growth rates in the coarse-grained material. Contrary to the combined fracture mechanism in coarse-grained Ti only transcrystalline crack growth was a characteristic feature of crack propagation in the ultrafine-grained material.nIt has been found that the experimentally and theoretically determined values of closure are in reasonable agreement. Crack closure calculated according to the Newman model taking into account only plasticity induced closure was in the range from 67% to 69% of Kmax for as-received and 70% for UFG state of material. Crack closure determined experimentally was 67% of Kmax for as-received and 67% for UFG CP Ti grade 4.nInvestigation of fracture surfaces did not bring any evident signs of the effects of fracture surface morphology resulting in roughness induced closure or oxide induced closure under testing conditions used. This indicates that plasticity induced closure seems to be a dominant closure mechanism in both states of the investigated Ti grade 4.

Název v anglickém jazyce

Fatigue crack propagation in UFG Ti grade 4 processed by severe plastic deformation

Popis výsledku anglicky

Fatigue crack growth was investigated in commercially pure Ti grade 4 processed by severe plastic deformation. The ultrafine-grained structure was prepared by means of equal channel angular pressing technique followed by cold drawing. The growth of fatigue cracks was investigated also in the as-received coarse-grained state of material for comparison.nThe fatigue crack growth rate in the ultrafine-grained material was found to be higher and the threshold stress intensity range delta Kth for crack growth lower than in the coarse-grained Ti, 2.5 and 4.7 MPa m1/2, respectively. A combination of transcrystaline and intercrystaline crack growth was typical for all crack growth rates in the coarse-grained material. Contrary to the combined fracture mechanism in coarse-grained Ti only transcrystalline crack growth was a characteristic feature of crack propagation in the ultrafine-grained material.nIt has been found that the experimentally and theoretically determined values of closure are in reasonable agreement. Crack closure calculated according to the Newman model taking into account only plasticity induced closure was in the range from 67% to 69% of Kmax for as-received and 70% for UFG state of material. Crack closure determined experimentally was 67% of Kmax for as-received and 67% for UFG CP Ti grade 4.nInvestigation of fracture surfaces did not bring any evident signs of the effects of fracture surface morphology resulting in roughness induced closure or oxide induced closure under testing conditions used. This indicates that plasticity induced closure seems to be a dominant closure mechanism in both states of the investigated Ti grade 4.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20306 - Audio engineering, reliability analysis

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

International Journal of Fatigue

ISSN

0142-1123

e-ISSN

—

Svazek periodika

98

Číslo periodika v rámci svazku

MAY

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

8

Strana od-do

187-194

Kód UT WoS článku

000398008100018

EID výsledku v databázi Scopus

2-s2.0-85011407783