TY - JOUR
T1 - Different approaches for the verification of force values measured with instrumented charpy strikers
AU - Lucon, Enrico
AU - Chaouadi, Rachid
AU - van Walle, Eric
N1 - Score = 10
PY - 2005/12/21
Y1 - 2005/12/21
N2 - The Charpy test plays a fundamental role in the nuclear field for evaluating the neutron embrittlement of the reactor pressure vessel, specifically within the so-called Enhanced Surveillance Approach, developed at SCK•CEN and aimed at extracting as much information as possible from Charpy impact tests performed with an instrumented striker. Careful analysis of the instrumented force/deflection traces allows defining important parameters which can help investigate material characteristics such as flow properties, microcleavage fracture stress, crack arrest behavior and alternative characteristic (index) temperatures. For this advanced approach to be successfully applied, confidence in the quality of instrumented force values must be high; as a consequence, extensive research has been performed in order to establish an optimal procedure for the verification of instrumented Charpy strikers. Various approaches will be described in this paper and their applicability and effectiveness discussed. A procedure based on the comparison between yield stresses measured from tensile tests and calculated from instrumented Charpy curves has recently been adopted at SCK•CEN as the recommended in-house procedure for verifying instrumented strikers. This method has shown that for all strikers investigated, the so-called “dynamic” calibration (based on the equalization of dial and calculated energies) yields the most accurate results.
AB - The Charpy test plays a fundamental role in the nuclear field for evaluating the neutron embrittlement of the reactor pressure vessel, specifically within the so-called Enhanced Surveillance Approach, developed at SCK•CEN and aimed at extracting as much information as possible from Charpy impact tests performed with an instrumented striker. Careful analysis of the instrumented force/deflection traces allows defining important parameters which can help investigate material characteristics such as flow properties, microcleavage fracture stress, crack arrest behavior and alternative characteristic (index) temperatures. For this advanced approach to be successfully applied, confidence in the quality of instrumented force values must be high; as a consequence, extensive research has been performed in order to establish an optimal procedure for the verification of instrumented Charpy strikers. Various approaches will be described in this paper and their applicability and effectiveness discussed. A procedure based on the comparison between yield stresses measured from tensile tests and calculated from instrumented Charpy curves has recently been adopted at SCK•CEN as the recommended in-house procedure for verifying instrumented strikers. This method has shown that for all strikers investigated, the so-called “dynamic” calibration (based on the equalization of dial and calculated energies) yields the most accurate results.
KW - Instrumented Charpy tests
KW - Enhanced Surveillance Approach
KW - Dynamic yield stresses
KW - Dynamic calibration of instrumented strikers
UR - http://ecm.sckcen.be/OTCS/llisapi.dll/open/ezp_32192
U2 - 10.1520/JAI12876
DO - 10.1520/JAI12876
M3 - Article
SN - 1546-962X
VL - 3
SP - 1
EP - 10
JO - Journal of ASTM International
JF - Journal of ASTM International
IS - 3
ER -