Notch-beam method

ASTM D 5379. Shear properties of composite materials by the V-notched beam method. 

Table 13. Properties of optimized TiB2-hard metals. ICL Indendation-crack-length method, NB notch-beam method.

ASTM D 5379-05 (2005), Standard test method for shear properties of composite materials by the notched beam method, ASTM, West Conshohocken, PA. 

Sharp V notches were introduced in flexure test specimens, using the single-edge-v-notched-beam method. This method utilizes a razor blade with diamond paste to... 

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. "... 

ASTM D5379/D5379m -12, Standard Test Method for Shear Properties of Composite Materials by the V-Notched Beam Method." in., ASTM International, West Conshohocken, PA, 2012. 

There are two main techniques used to measure the fracture toughness of ceramics fracture stress and hardness indentation. The former measures the load to fracture of a pre-cracked specimen using a single edge notched beam (SENB) or a chevron notched beam (CNB) sample. The main drawback of this technique is ensuring that the crack tip is atomically sharp. The second method uses the crack formed at the corners of the indentation produced during a Vickers indentation hardness test. This technique is rapid and relatively inexpensive. However, the toughness values measured are those of the surface, unlike the values obtained by fracture of the pre-cracked beams which are a measure of the bulk material properties. 

The equations for monolithic ceramics together with the experimental results of the notched specimen are used to determine the fracture toughness (represented as KIC) of the 3-D C/SiC composites created with the single edge notched beam (SENB) method. Its value is calculated as 20.3 MPa-m1/2, which is much higher than that of monolithic ceramic materials (3 to 5 MPa-m1/2). It should be noted that... 

ISO 23146, Fine ceramics (advanced, advanced technical ceramics) - Test methods for toughness of monolithic ceramics - Single-edge V-notched beam (SEVNB) method, (2008). 

Shilang Xu, H.W. Reinhardt. 1999. Determination of double-K criterion for crack propagation in quasi-brittle fracture. Part II Analytical evaluating and practical measuring methods for three-point bending notched beams. International Journal of Fracture. (98) 151-177. 

ISO (2005) 24370. Fine Ceramics (Advanced Ceramics, Advanced Tedmical Ceramics) — Determination of Fracture Tou ness of Monolithic Ceramics at Room Temperature by the Chevron-notched Beam (CNB) Method, International Organization for Standardization. 

Single crystals of zirconia and alumina were tested by SEVNB and by the single-edge notched beam (henceforth SENB) method, and the results are shown... 

A recent use of equation (5.73) to determine K,c values as a function of grain size for alumina compares results to notched beam tests. The broken arms of the beams were used for the indentation-strength in bending test (ISB). Thus a good comparative study was possible. Figure 5.16 shows the close correspondence between the ISB results and the earlier results of Rice et using a double cantilever beam method. 

R. Moon, K. Bowman, K. Trumble, J. Roedel, Comparison of R curves from single edge V notch beam (SEAfB) and surface crack in flexure(SCF) fracture toughness test methods on multilayered alumina zirconia composites, J. Am. Ceram. Soc. 83 [2] 445 47 (2000)... 

The first of the two common methods for testing fracture toughness is called the single-edge notched beam (SEND) test. The set-up for this test is shown in Figure 15.25. The load is applied through the top two rollers until the specimen fractures. This fracture load is noted as Ffr ct. and substituted in Equation 15.58. In this equation, is a calibration factor. The drawback of this test is that we may not always obtain an atomically sharp crack. 

V-notched beam shear method (or losipescu) specimen dimensions (in mm) and loading... 

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