Though more parameters used for quantifying the effect of crack in structural component plane strain fracture
toughness is the frequently used one.
At present, a single stress or strain fracture
criterion cannot explain the failure fracture behavior under the complex stress state of a magnesium alloy material.
The tensile strength, Young's modulus, and nominal strain fracture
of the scaffolds were obtained by averaging the values from five samples.
The fracture mechanics parameters taken into considerations were those for the AISI 1022 steel: for Forman equation c = 1.447 x [10.sup.-12], n = 3.6, m = 1 (Forman et al., 1967); the plane stress fracture toughness [K.sub.C] = 110 MPa [m.sup.1/2], respectively the plane strain fracture
toughness [K.sub.IC] = 77 MPa [m.sup.1/2], the threshold stress intensity factor range under which the crack do not propagates [DELTA]K = 1.5 MPa [m.sup.1/2].
The plane strain fracture
toughness and tension tests of the steels investigated were carried out by Krasowsky and Krasiko  at the Institute for Strength Problems (Kiev, Ukraine).
Johnson, The Role of Large Crack Tip Geometry Changes in Plane Strain Fracture
, Division of Engineering, Brown University, U.S.
Drawing on a compendia of sources assembled by Hudson and Seward (cited in (6)), representative values of plane strain fracture
toughness, [K.sub.Ic], can be collected and estimates of its variability made.
The purpose of fracture toughness testing is to determine the value of the critical stress intensity factor, or plane strain fracture
The maximum circumferential strain fracture
criterion for mixed mode of concrete, The Journal of Northwest Agriculture University 27(1): 43-46.
McClintock and Leguilon [3, 4] offered strain fracture
criteria when plastic zone at crack tip is taken into account and stresses [[sigma].sub.[infinity]] are calculated:
The relatively low strength of PE necessitates a thick pipe wall, which in turn favors plane strain fracture
. Unfortunately PE--like many thermoplastics--also has relatively little resistance to plane strain fracture
at crack speeds, exceeding 100m/s and temperatures below 0[degrees]C.
5-8), compact specimens with cracks were used to measure the plane strain fracture