TY - JOUR
T1 - Interaction of a screw dislocation with Cu-precipitates, nanovoids and Cu–vacancy clusters in BCC iron
AU - Terentyev, Dmitry
AU - Malerba, Lorenzo
A2 - Konstantinovic, Milan
N1 - Score = 10
PY - 2012/2/1
Y1 - 2012/2/1
N2 - In a previous work we studied the interaction of a ½h111i{110} edge dislocation with Cu-rich precipitates
containing also vacancies and Ni, thereby mimicking precipitates known to form in RPV steels
[1]. Here, we extend the study and consider the interaction of the Cu-rich precipitates with ½h111i screw
dislocations, known to govern the slip in BCC metals and alloys below room temperature. The results
show that three different mechanisms take place upon interaction of a screw dislocation with pure Cu
precipitates, nanovoids and Cu–vacancy clusters. Pure Cu precipitates are always sheared, while in the
reaction with nanovoids local climb, especially at high temperature, is also observed. The interaction
mechanisms studied at various temperatures reveal that the penetration of the screw dislocation into
Cu–vacancy clusters leads to absorption of the majority of the vacancies on the dislocation line, with
the consequent formation of a helical turn. The removal of the helical turn, even a very small one, from
the dislocation line requires as high stress as for the passage through a row of nanovoids of comparable
size.
AB - In a previous work we studied the interaction of a ½h111i{110} edge dislocation with Cu-rich precipitates
containing also vacancies and Ni, thereby mimicking precipitates known to form in RPV steels
[1]. Here, we extend the study and consider the interaction of the Cu-rich precipitates with ½h111i screw
dislocations, known to govern the slip in BCC metals and alloys below room temperature. The results
show that three different mechanisms take place upon interaction of a screw dislocation with pure Cu
precipitates, nanovoids and Cu–vacancy clusters. Pure Cu precipitates are always sheared, while in the
reaction with nanovoids local climb, especially at high temperature, is also observed. The interaction
mechanisms studied at various temperatures reveal that the penetration of the screw dislocation into
Cu–vacancy clusters leads to absorption of the majority of the vacancies on the dislocation line, with
the consequent formation of a helical turn. The removal of the helical turn, even a very small one, from
the dislocation line requires as high stress as for the passage through a row of nanovoids of comparable
size.
KW - PRV steel
KW - hardening
UR - http://ecm.sckcen.be/OTCS/llisapi.dll/open/ezp_125650
UR - http://knowledgecentre.sckcen.be/so2/bibref/9672
U2 - 10.1016/j.jnucmat.2011.11.037
DO - 10.1016/j.jnucmat.2011.11.037
M3 - Article
SN - 0022-3115
VL - 421
SP - 32
EP - 38
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
IS - 1-3
ER -