Acoustic emission from cleavage microcracking in alloy steels

Fracture Toughness Determination of Heat Treated AISI D2 Tool Steel Using AE Technique

“…In previous works 4,5,15,16) almost all investigators have used the point corresponding to the first jump in AE cumulative counts plot as the critical load (P Q ). Notwithstanding the advantages of this method, because of that this first jump is probably corresponded to pop-in fracture especially in brittle materials, in some cases, there are sizable differences between fracture toughness values calculated using this method in comparison with the standard ASTM E 399 results.…”

“…To exploit this potential of AE, extensive work has been done using AE studies to understand fracture processes. [3][4][5][6][7][8] Moreover, some investigators [9][10][11][12] have carried out conventional fracture toughness tests in liaison with AE monitoring; however, calculating K IC value using AE technique in current studies is few in number. These numerable investigations have used acoustic emission cumulative counts (AECC) characteristic to determine the critical load value (P Q ).…”

Fracture Toughness Evaluation of 316LN Stainless Steel and Weld Using Acoustic Emission Technique

“…[1][2][3] Arli et al, 1) in an early work, concluded that the point of crack initiation could be described as the significant change in the slope of total AE counts versus COD value. In the case of two grades of medium and high strength steels, the crack initiation during fracture toughness tests was determined by the sudden change in the slope of total AE energy versus J curve.…”

“…For utilizing this ability of AE, several investigators have performed extensive fracture toughness tests by AE technique to estimate the fracture toughness values. [1][2][3][4][5][6][7][8][9][10][11] However, the approaches are different. In some investigations, changes in the slope of AE parameters versus fracture mechanic parameters such as crack opening displacement…”