13th International Conference on Fracture June 16–21, 2013, Beijing, China 2 fatigue crack propagation rate. The present analysis is limited to a two-dimensional configuration by the plane strain assumption. 2. Experimental arrangement 2.1. Material and specimens The material used in the present investigation comes with 304 austenitic stainless steel cylindrical bars with a 200mm diameter. The mechanical properties were obtained through tensile test performed on cylindrical specimen of 6mm diameter and about 70mm gauge length. The C(T) specimens were fabricated following the ASTM E399. The dimensions of C(T) specimen are illustrated in Figure 1(a). The material curves are shown in Figure 1(b). (a) (b) Figure 1. (a) Dimensions of C(T) specimen, the thickness is 12.5mm. (b) Engineering and true stress-strain curves for the stainless 304 steel. 2.2. Experimental apparatus and conditions The configuration of clevis used for C(T) specimen is based on ASTM E647. All fatigue pre-cracks of the specimens were generated under mode I loading using high frequency testing machine at a loading frequency of approx. 90 Hz. The fracture test was conducted to determine the plane strain fracture toughness of the stainless steel 304. Fatigue loading during the crack growth process was carried out in a MTS servo-hydraulic testing machine. (a) (b) Figure 2. (a) The compliance method and (b) beachmarks on the fracture surface for CT specimen.
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