Evaluating Schmid criterion for predicting preferential locations of persistent slip markings obtained after very high cycle fatigue for polycrystalline pure copper

Phung, Ngoc-Lam; Favier, Véronique; Ranc, Nicolas

doi:10.1016/j.ijfatigue.2015.03.009

Cited by 11 publications

(11 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to the recognition of the importance of Schmid factors with respect to dislocation slip, some authors [19][20][21][22][23][24] have utilised these key microstructural quantities to understand local micromechanical behaviour for crack nucleation. Birosca et al [19] utilised the Schmid factor, Taylor factor and GND density to address the effect of local texture on crack propagation path in Ni superalloy and found that secondary cracks are more prone to nucleate on triple junctions between soft and hard orientated grains, and the Taylor factor parameter was found not to give any direct indication of dislocation activity within a grain.…”

Section: Introductionmentioning

confidence: 99%

“…Though these studies used Schmid parameters to link with failure, experimental studies by Risbet et al [22] have shown local damage initiation of fatigue extrusion heights in Ni-superalloy have both high and low Schmid factors. More recent modelling work by Phung et al [23] used the Schmid criterion to predict preferential sites of persistent slip marking (PSM) only to conclude that the prediction of the two different types of PSMs they considered could not be achieved. Understanding local slip behaviour in micro-volumes [25] or macrozones in Ti 6Al 4V [26] from macroscopic stress states also remains problematic.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

An HR-EBSD and computational crystal plasticity investigation of microstructural stress distributions and fatigue hotspots in polycrystalline copper

et al. 2016

View full text Add to dashboard Cite

High resolution EBSD studies on a deformed copper polycrystal have been carried out to quantify the microstructural residual stress distributions, and those of stress state including triaxiality of importance in defect nucleation studies. Crystal plasticity analysis of a representative, similarly textured, model polycrystal has been carried out showing that the experimental distributions of microstructural residual stress components, effective stress, hydrostatic stress and stress triaxiality are well captured.The crystal model enables point-wise microstructural Schmid factors to be calculated both globally (ie with respect to the macroscopic remote loading) and locally from full knowledge of the grain-level stress state. Significant differences are demonstrated such that global Schmid analysis tends to overestimate slip activity and the frequency of high Schmid factors, indicating that the local microstructural heterogeneity is significant and caution is necessary in interpreting polycrystal behaviour using global Schmid factors. A stored energy criterion for fatigue crack nucleation indicates that preferential sites for fatigue crack nucleation are local to grain boundaries (as opposed to triple junctions), and that hard-soft grain interfaces where high GND densities develop are preferable.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

An HR-EBSD and computational crystal plasticity investigation of microstructural stress distributions and fatigue hotspots in polycrystalline copper

et al. 2016

View full text Add to dashboard Cite

show abstract

“…The anisotropy coefficient value of 3.3 for copper is quite high [17]. Combining observations of slip markings and polycrystalline anisotropic elastic modelling, it was proved that it is due to: (1) higher components of the local stress tensor due to strain incompatibilities related to cubic elasticity and (2) well-oriented slip system with the slip plane parallel to the twin boundary plane [18]. Polak and Vasek [19] observed PSBs similar to type II persistent slip markings at strain amplitudes lower than the ''conventional fatigue limit'' (Δ/2 = 510 -5 [16]) in polycrystalline copper.…”

Section: Resultsmentioning

confidence: 99%

Energy Dissipation in Very High Cycle Fatigue for Polycrystalline Pure Copper and Armco Iron

Blanche

Wang

Phung

et al. 2015

KEM

View full text Add to dashboard Cite

This paper aims at a deeper understanding of microplastic mechanisms leading to crack initiation in ductile metals in Very High Cycle Fatigue (VHCF). Fatigue tests were conducted using an ultrasonic technique at loading frequency of 20 kHz. The microplastic mechanisms are revealed via observations of slip markings at the specimen surface and self-heating measurements due to intrinsic dissipation. Pure copper and Armco iron (which contains a very low amount of carbon) were investigated. Both are single-phase ductile materials but the crystallographic structure of copper is face-centered cubic while it is body centered cubic for Armco iron. A good correlation was found between slip markings initiation and dissipation for both materials. The dissipation for both materials is of the same order of magnitude but the location, the morphology and the evolution over cycles of slip markings were found different.

show abstract

“…It is commonly accepted that the microplasticity associated with the irreversible cyclic slip is the primary VHCF mechanism in the pure polycrystalline copper [19][20][21][22]. Hence, the plastic strain amplitude is considered as a more intrinsic fatigue indicator than the stress amplitude and is therefore preferred to be related with the fatigue life.…”

Section: The Fatigue Life Diagrammentioning

confidence: 99%

“…Nevertheless, the non-metallic inclusion is not the sole cause of the VHCF in metals. For a material that is not possessed of any inclusion, it can still fail after a sufficiently high number of cycles [19][20][21][22]. The fatigue failure could be due to irreversible slip accumulation or other reasons.…”

Section: Introductionmentioning

confidence: 99%

A microplasticity evaluation method in very high cycle fatigue

Wang

Feng

Jiang

2017

International Journal of Fatigue

View full text Add to dashboard Cite

This paper focuses on the development of a calorimetric method for the microplasticity evaluation in the very high cycle fatigue regime. The proposed method is essentially based on the establishment of an experimental energy balance during the fatigue process. It allows the estimation of the plastic strain of very low magnitude produced by cyclic slip, which is considered as the primary mechanism of the ultrahigh cycle fatigue in the face-centered cubic materials. By the developed method, the plastic strain amplitudes of a polycrystalline copper in the very high cycle fatigue regime are estimated, and its relationship with the fatigue lives is established via the Manson-Coffin law.

show abstract

Evaluating Schmid criterion for predicting preferential locations of persistent slip markings obtained after very high cycle fatigue for polycrystalline pure copper

Cited by 11 publications

References 34 publications

An HR-EBSD and computational crystal plasticity investigation of microstructural stress distributions and fatigue hotspots in polycrystalline copper

An HR-EBSD and computational crystal plasticity investigation of microstructural stress distributions and fatigue hotspots in polycrystalline copper

Energy Dissipation in Very High Cycle Fatigue for Polycrystalline Pure Copper and Armco Iron

A microplasticity evaluation method in very high cycle fatigue

Contact Info

Product

Resources

About