Brittle fracture of U-notched graphite plates under mixed mode loading

Review of local strain energy density theory for the fracture assessment of V-notches under mixed mode loading

“…In order to better investigate the notch sensitivity of isostatic graphite, considering different failure modes, a large experimental program has been conducted by Berto et al (2012aBerto et al ( , 2012bBerto et al ( , 2013 and Lazzarin et al (2013). The fracture tests were carried out on a commercial isostatic polycrystalline graphite.…”

“…These points were also highlighted by Greenstreet (1968) and Greenstreet et al (1969). Berto et al (2012aBerto et al ( , 2012bBerto et al ( , 2013 and Lazzarin et al (2013) in their experimental work, used a single value for elastic modulus obtained through a load-displacement graphs. The deviation of the tested specimens from linear behavior at failure was less than 0.02%.…”

“…They proposed a mean stress criterion to the estimation of their experimental results, with a very good accuracy. Since the industrial relevance of notched components made in graphite under mixed mode loading (as shown in the Introduction) and the literature lack, the first part of the experimental program carried out by Berto et al (2012aBerto et al ( , 2012bBerto et al ( , 2013 and Lazzarin et al (2013) was dedicated to the investigation of mixed mode brittle fracture in polycrystalline graphite from experimental and theoretical viewpoint Berto et al (2012b) and Lazzarin et al (2013). First, with the aim to determine the fracture loads under different combinations of mode I and II load, different fracture experiments are conducted on centrally notched specimens, more specific U-notches and key-holes were considered.…”

“…Worth mentioning are some pioneering papers (Bazaj & Cox, 1969;Kawakami, 1985) and some quite recent contributions (Ayatollahi et al, 2011a;Mostafavi et al, 2013a). In order to investigate the notch sensitivity of isostatic graphite, remarkable experimental program has been conducted by Berto and coworkers (Berto et al, 2012a(Berto et al, , 2012b(Berto et al, , 2013Lazzarin et al, 2013) considering different failure modes. Several test specimens and fracture models have been used in the past for investigating the mixed mode tensile-shear fracture behaviour of brittle materials (e.g.…”

Large plasticity induced crack initiation from U-notches in thin aluminum sheets under mixed mode loadin

“…Moreover, because EMC acts as a bridge between the linear elastic and elastic-plastic analyses, it is expected that it can basically be linked to various brittle fracture criteria, e.g. the maximum tangential stress (MTS) and mean stress (MS) (Ayatollahi & Torabi, 2010a, 2010bTorabi, 2013d;Ayatollahi et al, 2011aAyatollahi et al, , 2011bAliha & Ayatollahi 2013;Mirsayar et al 2014;Torabi et al, , 2014dTorabi & Amininejad, 2015aTorabi & Pirhadi 2015;Torabi & Abedinasab, 2015a criteria, the averaged strain energy density (ASED) criterion (Lazzarin & Zambardi, 2001;Berto & Lazzarin, 2014;Torabi et al, , 2015cBerto & Barati, 2011;Gomez et al, 2007Gomez et al, , 2009aGomez et al, , 2009bBerto et al, 2007Berto et al, , 2012Berto & Ayatollahi, 2011;Berto & Lazzarin, 2009;Aliha et al 2016), the cohesive zone model (CZM) (Gomez et al, 2000(Gomez et al, , 2006Gomez & Elices, 2003;Cendon 42 et al, 2015) and the finite fracture mechanics (FFM) (Sapora et al, 2013(Sapora et al, , 2015Cornetti et al, 2012Cornetti et al, , 2014Weißgraeber & Becker, 2013;Carpinteri et al, 2008) etc. under different in-plane loading conditions.…”