CHEN Huangpu DENG Zengjie Xi'an Jiaotong University
,
Xi'an
,
China CHEN Huangpu
,
Lectuer
,
Research Institute for Strength of Metals
,
Xi'an Jiaotong University
,
Xi'an 710049
,
China
金属学报(英文版)
The resistance to crack propagation at earlier stage for a high strength structural steel with certain ductility and its correlation to microstructures,stress states,deformation history and strain characteristics have been investigated.The resistance to crack propagation is mainly de- termined by the plastic constrain ahead of the crack tip,the elastic energy and plastic work absorbed in the stress-strain field.These are connected with the state function of triaxial stress.The deformation history and strain characteristic during deformation of material are described by the flow line in which the deformation history and strain characteristic restrain the crack initiation at stage Ⅱ and the crack propagation at stage Ⅲ.The strain hardening rate may sensitively reflect the stress distribution and micro-fracture mechanism in the interi- or of material.
关键词:
high strength structural steel
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null
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null
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HE Jiawen HU Naisai ZHANG Dingquan Xi'an Jiaotong University
,
Xi'an
,
China Professor
,
Research Institute for Strength of Metals
,
Xi'an Jiaotong University
,
Xi'an 710049
,
China
金属学报(英文版)
Residual stress concentration at a notch depends on both notch geometry and yield strength of the material.It varies through the depth,and its magnitude may be higher than the theoretical one.Compressive residual.stress concentration at the notch of shot-peened specimen of soft material is easily to he relaxed,with the surface damage during shot-peening results in a mi- nor contribution to the fatigue limit.Compressive residual stress increases the crack closure effect at the notch and may lead to a non-propagating crack.
关键词:
residual stress
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null
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