Single-edge precracked-beam method

T. Nose and T. Fujii, Evaluation of Fracture Toughness for Ceramic Materials by a Single-Edge-Precracked-Beam Method, Journal of the American Ceramic Society, 71[5], 328-333 (1988). 

Nose, T. and Fujii, T., Evaluation of fracture toughness for ceramic materials by a single-edge-precracked beam method, J Am. Ceram. Soc., 1988, 71, pp. 328-33. 

Fracture tougnness was determined with the single-edge-precracked-beam (SERB) and chevron-notch° methods in three-point bending. 

ASTM C 1421 for advanced ceramics includes three related test method procedures as illustrated in Figure 2. The three methods are the surface crack in flexure (SCF), precracked beam (PB) [also known as single-edge precracked beam (SEPB)], and chevron notch in bending (CNB) methods. The content and development of C 1421 and its precursor, ASTM PS 070-97 are documented elsewhere [2,3,4,5]. The SRM may also be used with three ISO standard test methods that are under development in Technical Committee TC 206, based on the SEPB, SCF, and CNB methods. It may also be used with a draft CEN standard that features SCF, CNB, SEPB, and single edge-V-notched beam methods, as well as JIS R 1607 which has the SEPB method. "... 

ISO 15732, Fine Ceramics (Advanced Ceramics, Advanced Technical Ceramics) Test Method for Fracture Toughness at Room Temperature by Single Edge Precracked Beam (SEPB) Method, International Organization for Standards, Geneva, 2003. 

This test method can be used to measure the relative susceptibility of materials by "Determining the Threshold Stress Intensity Factor for Environment-Assisted Cracking EAC of Metallic Materials. Constant load specimens, both the fatigue precracked single edge beam SE(B) and precracked compact specimens are tested in bending. The SE(B) was originally referred to as the Cantilever Beam Test. 

The effect of test duration is demonstrated fqr a method used fy the Navy to compare materials for aircraft parts. A single-edge notched (and precracked) cantilever beam specimen is deadweight loaded and exposed to 3 1/2 % NaCl. The time-to-fad at various stress intensities is plotted in Fig. 8. The stress intensity after 1000 h exposure has been used as a measure of resistance, although lower values have been obtained if the specimens are allowed to continue for 10 000 h. 

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