Microstructure-sensitive computational modeling of fatigue crack formation

McDowell, David L.; Dunne, Fionn P.E.

doi:10.1016/j.ijfatigue.2010.01.003

Cited by 471 publications

(303 citation statements)

References 168 publications

Supporting

Mentioning

298

Contrasting

Unclassified

Order By: Relevance

“…As mentioned previously, crack initiation is expected to dominate over propagation in HCF, particularly in the case of micro-scale components, and it has been firmly established that FCI is a microstructurally-driven phenomenon [15][16][17]. Sangid [18] provides a comprehensive description of the build-up of dislocations and development of energy minimising dislocation structures leading to the formation of persistent slip bands, and subsequent crack initiation at the slip band-matrix interface.…”

Section: Introductionmentioning

confidence: 95%

Micro-scale testing and micromechanical modelling for high cycle fatigue of CoCr stent material

Sweeney

O’Brien

Dunne

et al. 2015

Journal of the Mechanical Behavior of Biomedical Materials

Self Cite

View full text Add to dashboard Cite

This paper presents a framework of experimental testing and crystal plasticity micromechanics for high cycle fatigue (HCF) of micro-scale L605 CoCr stent material.Micro-scale specimens, representative of stent struts, are manufactured via laser micromachining and electro-polishing from biomedical grade CoCr alloy foil. Crystal plasticity models of the micro-specimens are developed using a length scale-dependent, strain-gradient constitutive model and a phenomenological (power-law) constitutive model, calibrated from monotonic and cyclic plasticity test data. Experimental microstructural characterization of the grain morphology and precipitate distributions is used as input for the polycrystalline finite element (FE) morphologies. Two microstructure-sensitive fatigue indicator parameters are applied, using local and non-local (grain-averaged) implementations, for the phenomenological and length scale-dependent models, respectively, to predict fatigue crack initiation (FCI) in the HCF experiments.

show abstract

Section: Introductionmentioning

confidence: 95%

Micro-scale testing and micromechanical modelling for high cycle fatigue of CoCr stent material

Sweeney

O’Brien

Dunne

et al. 2015

Journal of the Mechanical Behavior of Biomedical Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…These inclusions are inevitable defects presenting in powder metallurgy alloy processing, as although extreme care has been taken contamination of powder cannot be avoided completely in melting, powder atomisation and handling, through to consolidation. It is found that non-metallic inclusions significantly degrade FGH96 low cycle fatigue life [2]. This motivates us to improve our understanding of this complex process, and we begin with low temperature fatigue crack nucleation utilising state of the art experimental techniques in order to improve fatigue life predictions, and deliver safer and more economical components.…”

Section: Introductionmentioning

confidence: 99%

“…Many recent reviews have outlined the importance of understanding of fatigue crack formation, and propagation mechanisms at the microstructure scale are critical to facilitate quantitative prediction of fatigue lifetime as a function of microstructure [2][3][4][5][6][7]. These reviews highlight the need to deliver new experimental insight into deformation processes and failure in fatigue to drive modelling that can accurately capture microstructurally-sensitive effects and use geometrically faithful models.…”

Section: Introductionmentioning

confidence: 99%

On the mechanistic basis of fatigue crack nucleation in Ni superalloy containing inclusions using high resolution electron backscatter diffraction

et al. 2015

View full text Add to dashboard Cite

This is an authors' copy of a manuscript published in Acta Materialia Volume 97, 15 September 2015, Pages 367-379. http://dx.doi.org/10.1016/j.actamat.2015.06.035 AbstractA series of interrupted three-point bend low-cycle fatigue tests were carried out on a powder metallurgy FHG96 nickel superalloy sample containing non-metallic inclusions. High resolution electron backscatter diffraction (HR-EBSD) was used to characterize the distribution and evolution of geometrically necessary dislocation (GND) density, residual stress and total dislocation density near a non-metallic inclusion. A systematic study of room temperature cyclic deformation is presented in which slip localisation, cyclic hardening, ratcheting and stabilisation occur, through to crack formation and microstructurally-sensitive propagation. Particular focus is brought to bear at the inclusion-matrix interface. Complex inhomogeneous deformation structures were directly observed from the first few loading cycles, and these structures were found not to vary significantly with increasing number of cycles. A clear link was observed between crack nucleation site and microstructurally-sensitive growth path and the spatially-resolved sites of extreme values of residual stress and GND density.

show abstract

“…Thus, microstructure barriers near the fatigue crack origin are responsible for crack initiation and determine the fatigue life scattering. On the contrary, fatigue cracks grow in elastic-plastic field with less microstructural influence for low cycle fatigue (LCF) [16]. Studies on VHCF mechanism have shown that it is the microstructure that plays an important role in the process of interior fatigue crack initiation with FGA morphology.…”

Section: Introductionmentioning

confidence: 99%

Effects of loading condition on very-high-cycle fatigue behaviour and dominant variable analysis

Lei

Xie

Sun

et al. 2013

Sci. China Phys. Mech. Astron.

View full text Add to dashboard Cite

The specimens of a high carbon chromium steel were quenched and tempered at 150°C, 180°C and 300°C. Such specimens were tested via rotating bending and a push-pull type of axial loading to investigate the influences of loading condition on the behaviour of very-high-cycle fatigue (VHCF). Experimental results show the different influences of inclusion size on the fatigue life for the two loading conditions. Predominant factors and mechanism for the fine-granular-area (FGA) of crack origin were discussed. In addition, a reliability analysis based on a modified Tanaka-Mura model was carried out to evaluate the sensitivity of inclusion size, stress, and K FGA to the life of VHCF crack initiation.

show abstract

Microstructure-sensitive computational modeling of fatigue crack formation

Cited by 471 publications

References 168 publications

Micro-scale testing and micromechanical modelling for high cycle fatigue of CoCr stent material

Micro-scale testing and micromechanical modelling for high cycle fatigue of CoCr stent material

On the mechanistic basis of fatigue crack nucleation in Ni superalloy containing inclusions using high resolution electron backscatter diffraction

Effects of loading condition on very-high-cycle fatigue behaviour and dominant variable analysis

Contact Info

Product

Resources

About