PSI - Issue 33

Jamaloddin Jamali et al. / Procedia Structural Integrity 33 (2021) 832–842 Author name / StructuralIntegrity Procedia 00 (2019) 000–000

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Mode I critical stress intensity factor for SENB and CT can be found from equations 1 and 2 below: Equation 1: Mode I critical stress intensity factor for CT Jamali et al. (2014, 2019, 2020) � � √ . � � � � � �.�6 � �.�6� � � �� � � � �.�� � � � �� � � �.��� � � �� � � (1) Where α=0 for mode I. The value of K can also be determined by using ASTM 5045 � � � � � . � � � � � �� � ���.��6 � �.6� � ��.�� � � ��.�� � � �.6 � � ��� � � � � (2) where, a is initial crack length, w is width of specimen, P is load applied, t is thickness of specimen and KI is the mode I fracture toughness. Equation 3: Mode I critical stress intensity factor for SENB �� � � � ��� � � � 6 ��� ��.�� � �� � ���.�� � �.�� � �.� � �� ��� � � ��� � � � � (3) where, w is width of specimen, P is load applied, B is thickness of specimen and KI is the mode I fracture toughness and X is a/w (0

Fig.4: (a) SENB 3D model design; (b) CT 3D model