Fracture behaviour of carbon materials

The shear fracture toughness, K, of graphite

“…Ouagne et al [36] confirmed the findings of Sakai et al [37,38] who attributed the Rcurve behavior of graphite to the non-linear processes, both in the microcracking frontal process zone and in the following wake region, and of grain bridging. Similar behavior was reported earlier for the carbon materials used in Aluminum reduction cells [23]. Sun et al [39] Ayatollahi and Torabi [15] discuss the fact that some graphites exhibit non-liner stress-strain response in a standard tension or compression test conducted on a plain test specimen.…”

“…The development of AE with applied load was shown to be associated with the micromechanical events that caused non-linear stress-strain behavior in graphites, and post fracture AE was indicative of the crack prorogation mode at fracture. Allard et al [23] studied fracture in anthracite based carbons (used in the aluminum smelting industry) and noted R-curve behavior during mode I fracture. The effect of neutron irradiation on the mode I fracture toughness of grade PCEA graphite was examined by Burchell and Strizak [24,25], who showed that K Ic can be expected to increase upon neutron irradiation.…”

Room temperature long-term creep/relaxation behaviour of carbon cathode material

“…the van der Waals bonds. It as been observed for an anthracitic cathode block material [39] that cracks tend to grow between the sheets of the grains or round them if the grains is perpendicular to the cracks, as shown in Fig. 16.…”

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

“…Since the strategic importance of this variable, several researchers have tried to determine the fracture toughness of polycrystalline graphite under mode I or under mixed mode tensile-shear loading conditions (e.g. Yamauchi et al, 2000Yamauchi et al, , 2001Wang & Liu, 2008;Etter et al, 2004;Yum & You, 2001;Wosu et al, 2005;Jurf & Pipes, 1982;Latella & Liu, 2006;Sato et al, 1978Sato et al, , 1981Knibbs, 1967;Allard et al, 1991;Burchell, 1996;Lomakin et al, 1975;Losty, 1962;Greenstreet, 1968;Greenstreet et al, 1969;Aliha et al, 2015a;Nemeth, 2011;Mostafavi et al, , 2013aMostafavi et al, , 2013b. Especially Awaji and Sato (1978), Li et al (1999), Yamauchi et al (2000Yamauchi et al ( , 2001, and Shi et al (2008) conducted a large number of tests to determine fracture toughness under mode I and mixed mode I+II with different cracked specimens.…”

“…Several researchers have pushed their efforts in this direction (e.g. Knibbs, 1976;Allard et al, 1991;Burchell, 1996;Lomakin et al, 1975;Losty, 1962;Greenstreet, 1968;Greenstreet et al, 1969;Nemeth, 2011;Mostafavi & Marrow, 2011Bahmani et al, 2017;Akbardoost, 2014;Mirsayar et al, 2016). Among them, a well-known theory was proposed by Burchell (1996).…”