Abstract
In the present research, two stress-based failure criteria were proposed to predict brittle fracture in components containing V-notches with end holes (VO-notches) under mixed mode I/II loading. The first criterion, called VO-MTS, was an extension of the maximum tangential stress (MTS) criterion, and the second one, called VO-MS, was developed based on the mean stress (MS) failure concept. Two different groups of critical distances were utilized in the predictions. The first group was equal to the critical distances for sharp crack, and the second one was computed by using the mode I fracture test results on notched specimens. To verify the criteria, the theoretical fracture curves were compared with numerous experimental results gathered from 108 new brittle fracture tests performed on the Brazilian disk specimens weakened by central V-notches with end holes and made of PMMA under mode I and mixed mode I/II loadings. It was found that both the criteria provide very good predictions to the experimental results for different mode mixity ratios. Also, found in this research was that the curves are almost independent of the critical distance groups, meaning that one can simply utilize the critical distances of sharp crack in both the VO-MTS and the VO-MS criteria without requiring performing mode I VO-notch fracture experiments.
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Abbreviations
- CTSN:
-
Compact–tension–shear–notch
- CZM:
-
Cohesive zone model
- d:
-
Total slit length in the VO-BD specimen
- D:
-
Diameter of the VO-BD specimen
- d c :
-
Critical distance of the MS criterion for sharp cracks
- d c,vo :
-
Critical distance of the MS criterion for VO-notch
- E :
-
Young’s modulus
- ERNFT:
-
Effective relative notch fracture toughness
- FE:
-
Finite element
- FFM:
-
Finite fracture mechanics
- FNR:
-
Fictitious notch radius
- \({K_{\rm eff}^{\rm vo}}\) :
-
Effective relative notch fracture toughness
- K IC :
-
Plane-strain fracture toughness of material
- \({K_{\rm I}^{\rm vo}}\) :
-
Mode I notch stress intensity factor
- \({K_{\rm II}^{\rm vo}}\) :
-
Mode II notch stress intensity factor
- \({K_{\rm Ic}^{\rm vo}}\) :
-
Mode I notch fracture toughness
- MTS:
-
Maximum tangential stress
- MS:
-
Mean stress
- NDT:
-
Nondestructive testing
- NFM:
-
Notch fracture mechanics
- NFT:
-
Notch fracture toughness
- NSIF:
-
Notch stress intensity factor
- P:
-
Compressive load applied to the specimen
- PMMA:
-
Polymethyl-methacrylate
- PS:
-
Point stress
- r c :
-
Critical distance of the MTS criterion for sharp cracks
- r c,vo :
-
Critical distance of the MTS criterion for VO-notch
- SED:
-
Strain energy density
- TPB:
-
Three-point bending
- UNBD:
-
U-notched Brazilian disk
- VO-BD:
-
Brazilian disk specimen containing V-notch with end hole
- VO-notch:
-
V-notch with end hole
- β :
-
Loading angle in the VO-BD specimen
- β II :
-
Mode II loading angle in the VO-BD specimen
- λ i :
-
Eigenvalues
- ϕ i :
-
Auxiliary parameters in the stress field around the VO-notch
- \({\nu}\) :
-
Poisson’s ratio
- ρ :
-
Notch radius
- \({\sigma_{\rm u}}\) :
-
Ultimate tensile strength of material
- \({\sigma_{{\rm r}\theta}}\) :
-
In-plane shear stress
- \({\sigma_{\theta \theta}}\) :
-
Tangential stress
- \({\overline{\sigma_{\theta \theta}}}\) :
-
Average value of the tangential stress over the critical distance
- \({\sigma_{\rm c}}\) :
-
Critical stress
- \({\theta_0}\) :
-
Fracture initiation angle for the MTS criterion
- \({\theta_{0{\rm II}}}\) :
-
Fracture initiation angle for the MTS criterion under mode II loading
- \({\overline{\theta_0}}\) :
-
Fracture initiation angle for the MS criterion
- \({\overline{\theta_{0{\rm II}}}}\) :
-
Fracture initiation angle for the MS criterion under mode II loading
References
Yuan H.: Singular stress fields at V-notch tips in elastoplastic pressure-sensitive materials. Acta Mech. 118, 151–170 (1996)
Dornowski W., Perzyna P.: Localized fracture phenomena in thermo-visco-plastic flow processes under cyclic dynamic loadings. Acta Mech. 155, 233–255 (2002)
Bian L., Cheng Y., Taheri F.: Elasto-plastic analysis of critical fracture stress and fatigue fracture prediction. Acta Mech. 225(11), 3059–3072 (2014)
Bhat S., Narayanan S.: A computational model and experimental validation of shielding and amplifying effects at a crack tip near perpendicular strength-mismatched interfaces. Acta Mech. 216, 259–279 (2011)
Lauterbach B., Gross D.: The role of nucleation and growth of micro cracks in brittle solids under compression: a numerical study. Acta Mech. 159, 199–211 (2002)
Shindo Y., Narita F., Sato T.: Analysis of mode II interlaminar fracture and damage behavior in end notched flexure testing of GFRP woven laminates at cryogenic temperatures. Acta Mech. 187, 231–240 (2006)
Guo J.H., Lu Z.X., Feng. X.: The fracture behavior of multiple cracks emanating from a circular hole in piezoelectric materials. Acta Mech. 215, 119–134 (2010)
Brighenti R., Carpinteri A., Spagnoli A.: Influence of material microvoids and heterogeneities on fatigue crack propagation. Acta Mech. 225, 3123–3135 (2014)
Gogotsi G.A.: Fracture toughness of ceramics and ceramic composites. Ceram. Int. 29, 777–784 (2003)
Knesl Z.: A criterion of V-notch stability. Int. J. Fract. 48, 79–83 (1991)
Nui L.S., Chehimi C., Pluvinage G.: Stress field near a large blunted tip V-notch and application of the concept of the critical notch stress intensity factor (NSIF) to the fracture toughness of very brittle materials. Eng. Fract. Mech. 49, 325–335 (1994)
Seweryn A.: Brittle fracture criterion for structures with sharp notches. Eng. Fract. Mech. 47, 673–681 (1994)
Strandberg M.: Fracture at V-notches with contained plasticity. Eng. Fract. Mech. 69, 403–415 (2002)
Lazzarin P., Zambardi R.: A finite-volume-energy based approach to predict the static and fatigue behavior of components with sharp V-shaped notches. Int. J. Fract. 112, 275–298 (2001)
Lazzarin P., Lassen T., Livieri P.: A notch stress intensity approach applied to fatigue life predictions of welded joints with different local toe geometry. Fat. Fract. Eng. Mater. Struct. 26, 49–58 (2003)
Lazzarin P., Berto F., Radaj D.: Fatigue-relevant stress field parameters of welded lap joints: Pointed slit tip compared with keyhole notch. Fat. Fract. Eng. Mater. Struct. 32, 713–735 (2009)
Yosibash Z., Bussiba A., Gilad I.: Failure criteria for brittle elastic materials. Int. J. Fract. 125, 307–333 (2004)
Berto F., Lazzarin P., Yates J.R.: Multiaxial fatigue of V-notched steel specimens: a non-conventional application of the local energy method. Fat. Fract. Eng. Mater. Struct. 34, 921–943 (2011)
Gomez F.J., Elices M.: A fracture criterion for sharp V-notched samples. Int. J. Fract. 123, 163–175 (2003)
Gomez F.J., Elices M., Valiente A.: Cracking in PMMA containing U-shaped notches. Fat. Fract. Eng. Mater. Struct. 23, 795–803 (2000)
Carpinteri A., Cornetti P., Pugno N., Sapora A., Taylor D.: A finite fracture mechanics approach to structures with sharp V-notches. Eng. Fract. Mech. 75(7), 1736–1752 (2008)
Livieri P.: A new path independent integral applied to notched components under mode I loadings. Int. J. Fract. 123, 107–125 (2003)
Matvienko Y.G., Morozov E.M.: Calculation of the energy J-integral for bodies with notches and cracks. Int. J. Fract. 125, 249–261 (2004)
Berto F., Lazzarin P.: Relationships between J-integral and the strain energy evaluated in a finite volume surrounding the tip of sharp and blunt V-notches. Int. J. Solids Struct. 44, 4621–4645 (2007)
Livieri P.: Use of J-integral to predict static failures in sharp V-notches and rounded U-notches. Eng. Fract. Mech. 75, 1779–1793 (2008)
Barati E., Alizadeh Y., Aghazadeh J., Berto F.: Some new practical equations for rapid calculation of J-integral in plates weakened by U-notches under bending. Mater. Design 31, 2964–2971 (2009)
Barati E., Alizadeh Y.: A numerical method for evaluation of J-integral in plates made of functionally graded materials with sharp and blunt V-notches. Fat. Fract. Eng. Mater. Struct. 34, 1041–1052 (2011)
Becker T.H., Mostafavi M., Tait R.B., Marrow T.J.: An approach to calculate the J-integral by digital image correlation displacement field measurement. Fat. Fract. Eng. Mater. Struct. 35, 971–984 (2012)
Ayatollahi M.R., Torabi A.R.: Brittle fracture in rounded-tip V-shaped notches. Mater. Design 31, 60–67 (2010)
Ayatollahi M.R., Torabi A.R.: Tensile fracture in notched polycrystalline graphite specimens. Carbon 48, 2255–2265 (2010)
Torabi A.R.: Estimation of tensile load-bearing capacity of ductile metallic materials weakened by a V-notch: The equivalent material concept. Mater. Sci. Eng. A 536, 249–255 (2012)
Torabi A.R.: Fracture assessment of U-notched graphite plates under tension. Int. J. Fract. 181, 285–292 (2013)
Torabi A.R.: On the use of the Equivalent Material Concept to predict tensile load-bearing capacity of ductile steel bolts containing V-shaped threads. Eng. Fract. Mech. 97, 136–147 (2013)
Torabi A.R.: Ultimate bending strength evaluation of U-notched ductile steel samples under large-scale yielding conditions. Int. J. Fract. 180, 261–268 (2013)
Torabi A.R., Fakoor M., Pirhadi E.: Tensile fracture in coarse-grained polycrystalline graphite weakened by a U-shaped notch. Eng. Fract. Mech. 111, 77–85 (2013)
Torabi A.R., Berto F.: Fracture assessment of blunt V-notched graphite specimens by means of the strain energy density. Strength Mater. 45, 635–647 (2013)
Torabi, A.R., Berto, F.: Notch fracture toughness evaluation for a brittle graphite material. Mater. Perform. Charact. 3(3), 1–16 (2014)
Ayatollahi M.R., Torabi A.R.: Investigation of mixed mode brittle fracture in rounded-tip V-notched components. Eng. Fract. Mech. 77, 3087–3104 (2010)
Ayatollahi M.R., Torabi A.R.: Failure assessment of notched polycrystalline graphite under tensile-shear loading. Mater. Sci. Eng. A 528, 5685–5695 (2011)
Ayatollahi M.R., Torabi A.R.: Experimental verification of RV-MTS model for fracture in soda-lime glass weakened by a V-notch. J. Mech. Sci. Tech. 25, 2529–2534 (2011)
Ayatollahi M.R., Torabi A.R., Azizi P.: Experimental and theoretical assessment of brittle fracture in engineering components containing a sharp V-notch. Exp. Mech. 51, 919–932 (2011)
Ayatollahi M.R., Torabi A.R.: A criterion for brittle fracture in U-notched components under mixed mode loading. Eng. Fract. Mech. 76, 1883–1896 (2009)
Torabi A.R.: Sudden fracture from U-notches in fine-grained isostatic graphite under mixed mode I/II loading. Int. J. Fract. 181, 309–316 (2013)
Torabi A.R., Fakoor M., Pirhadi E.: Fracture analysis of U-notched disc-type graphite specimens under mixed mode loading. Int. J. Solids. Struct. 51, 1287–1298 (2014)
Susmel L., Taylor D.: The theory of critical distances to predict static strength of notched brittle components subjected to mixed-mode loading. Eng. Fract. Mech. 75, 534–550 (2008)
Susmel L., Taylor D.: On the use of the theory of critical distances to predict static failures in ductile metallic materials containing different geometrical features. Eng. Fract. Mech. 75, 4410–4421 (2008)
Susmel L., Taylor D.: The theory of Critical Distances to estimate lifetime of notched components subjected to variable amplitude uniaxial fatigue loading. Int. J. Fatigue 33, 900–911 (2011)
Yosibash Z., Priel E., Leguillon D.: A failure criterion for brittle elastic materials under mixed-mode loading. Int. J. Fract. 141, 291–312 (2006)
Chen D., Ozaki S.: Investigation of failure criteria for a sharp notch. Int. J. Fract. 152, 63–74 (2008)
Priel E., Yosibash Z., Leguillon D.: Failure initiation at a blunt V-notch tip under mixed mode loading. Int. J. Fract. 149, 143–173 (2008)
Tovo R., Livieri P., Benvenuti E.: An implicit gradient type of static failure criterion for mixed-mode loading. Int. J. Fract. 141, 497–511 (2006)
Gomez F., Elices M., Berto F., Lazzarin P.: Local strain energy to assess the static failure of U-notches in plates under mixed mode loading. Int. J. Fract. 145, 29–45 (2007)
Gomez F., Elices M., Berto F., Lazzarin P.: A generalized notch stress intensity factor for U-notched components loaded under mixed mode. Eng. Fract. Mech. 75, 4819–4833 (2008)
Gomez F., Elices M., Berto F., Lazzarin P.: Fracture of V-notched specimens under mixed mode (I+II) loading in brittle materials. Int. J. Fract. 159, 121–135 (2009)
Gomez F., Elices M., Berto F., Lazzarin P.: Fracture of U-notched specimens under mixed mode: experimental results and numerical predictions. Eng. Fract. Mech. 76, 236–249 (2009)
Berto F., Ayatollahi M.R.: Fracture assessment of Brazilian disc specimens weakened by blunt V-notched under mixed mode loading by means of local energy. Mater. Design 32, 2858–2869 (2010)
Lazzarin P., Berto F., Elices M., Gomez J.: Brittle failures from U- and V-notches in mode I and mixed, I+II, mode: a synthesis based on the strain energy density averaged on finite-size volumes. Fat. Fract. Eng. Mater. Struct. 32, 671–684 (2009)
Zappalorto M., Lazzarin P.: In-plane and out-of-plane stress field solutions for V-notches with end holes. Int. J. Fract. 168, 167–180 (2011)
Lazzarin P., Zappalorto M., Berto F.: Generalized stress intensity factors for rounded notches in plates under in-plane shear loading. Int. J. Fract. 170, 123–144 (2011)
Berto F., Zappalorto M.: Fictitious notch rounding concept applied to V-notches with end holes under mode I loading. Int. J. Fract. 171, 91–98 (2011)
Lazzarin P., Berto F., Ayatollahi M.R.: Brittle failure of inclined key-hole notches in isostatic graphite under in-plane mixed mode loading. Fat. Fract. Eng. Mater. Struct. 36(9), 942–955 (2013)
Kullmer G., Richard H.A.: Influence of the root radius of crack-like notches on the fracture load of brittle components. Arch. Appl. Mech. 76, 711–723 (2006)
Torabi, A.R., Abedinasab, S.M.: Fracture study on key-hole notches under tension: two brittle fracture criteria and notch fracture toughness measurement by the disk test. Exp. Mech. (2014). doi:10.1007/s11340-014-9949-0
Torabi A.R., Pirhadi E.: Stress-based criteria for brittle fracture in key-hole notches under mixed mode loading. Euro. J. Mech A/Solids. 49, 1–12 (2015)
Torabi, A.R., Berto, F., Campagnolo, A.: Experimental and theoretical investigation of brittle fracture in key-hole notches under mixed mode I/II loading. Acta Mech. 226, 2313–2322 (2015)
Berto F., Lazzarin P., Ayatollahi M.R.: Brittle fracture of sharp and blunt V-notches in isostatic graphite under pure compression loading. Carbon 63, 101–116 (2013)
Torabi A.R., Ayatollahi M.R.: Compressive brittle fracture in V-notches with end holes. Euro. J. Mech A/Solids. 45, 32–40 (2014)
Torabi, A.R., Amininejad, SH.: Brittle fracture in V-notches with end holes. Int. J. Damage Mech. (2014). doi:10.1177/1056789514538293
Torabi, A.R., Amininejad, SH.: Fracture assessment of VO-notches under mode II loading: experiments and theories. Theor. Appl. Fract. Mech. (2004). doi:10.1016/j.tafmec.2014.10.010
Torabi A.R., Berto F., Campagnolo A.: Local strain energy density to predict mode II brittle fracture in Brazilian disk specimens weakened by V-notches with end holes. Mater. Design 69, 22–29 (2015)
Novozhilov V.V.: On necessary and sufficient criterion of brittle fracture. Prikladnaja Matematica i Mechanika 33, 212–222 (1969)
Berto F., Lazzarin P., Radaj D.: Fictitious notch rounding concept applied to sharp V-notches: Evaluation of the microstructural support factor for different failure hypotheses. Part I: basic stress equations. Eng. Fract. Mech. 75(10), 3060–3072 (2008)
Berto F., Lazzarin P., Radaj D.: Fictitious notch rounding concept applied to sharp V-notches: Evaluation of the microstructural support factor for different failure hypotheses. Part II: microstructural support analysis. Eng. Fract. Mech. 76(9), 1151–1175 (2009)
Berto F., Lazzarin P., Radaj D.: Fictitious notch rounding concept applied to V-notches with root holes subjected to in-plane shear loading. Eng. Fract. Mech. 79, 281–294 (2012)
Radaj D., Lazzarin P., Berto F.: Generalised Neuber concept of fictitious notch rounding. Int. J. Fatigue 51, 105–115 (2013)
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Riazi, R., Torabi, A.R., Amininejad, S. et al. Combined tension–shear fracture analysis of V-notches with end holes. Acta Mech 226, 3717–3736 (2015). https://doi.org/10.1007/s00707-015-1404-5
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DOI: https://doi.org/10.1007/s00707-015-1404-5