Evaluation of ageing-induced embrittlement in an austenitic stainless steel by instrumented impact testing

Emphasis of Embrittlement Characteristics in 304L and 316L Austenitic Stainless Steel

“…The kinetics of aging embrittlement was established based on Arrhenius relationship. A constant activation energy was determined for 304L weld in the temperature range 335-400 °C, however, 316L weld showed different activation energy values in each temperature range [38].…”

Evaluation of fracture toughness and impact toughness of laser rapid manufactured Inconel-625 structures and their co-relation

“…However for materials exhibiting type II or type III load time traces and elastic plastic procedure has to be applied. Usually such traces have been analyzed using J-integral procedure assuming crack initiation occurs at maximum load [26,27]. Ghoneim and Hammad [33] proposed that fracture initiation occurs at a load equal to (P max + P GY )/2, while Norris [34] based on a comparison of finite element results with experimental data, reported that the time to crack initiation, t i , equals 40% of the time to reach the maximum load, t max .…”

“…Based on these critical considerations the value of E I in the Eqn. 4 is assumed as the energy absorbed up to the maximum load (P max ) and (P max + P GY )/2 in the load displacement traces of the Charpy impact tests [26,27,33]. Dynamic plane strain fracture toughness (K Id ) has been estimated from Charpy energy (C V ) by various researchers [22,32].…”

“…P-d traces have been analyzed using a J-integral or CTOD procedure assuming crack initiation at the maximum load [26,27]. It may be noted that fairly accurate estimate of dynamic yield strength of the material can be made from general yield load, P GY determined from the P-d plot of instrumented Charpy test [28,29].…”

“…Equation 4, given below is one of the most successful correlations applicable over a wide range of C V (3 -95J) and yield strength (270 to 815 MPa) [32]. [26,27], are higher with respect to experimentally evaluated results reported for LRMed IN-625 [8]. Whereas it is seen that the estimated J iD , values from C V results are close to experimentally evaluated fracture toughness values [8] considering the relations proposed by Ghoneim and Hammad [33] for both the as-LRMed and LRM-HT specimens.…”