IN SITU OBSERVATION OF DISLOCATION BEHAVIOR IN PLASTIC ZONE AHEAD OF A CRACK-TIP IN A CO-BASE SUPERALLOY
钴基高温合金尖塑性区位错结构的原位观察

This paper presents a study of dislocation behavior in a plastic zone ahead of a crack-tip in a Co-base superalloy during in situ deformation in a TEM. The results show that the dislocations emitted from the crack-tip are partials when the tensile acs is 51]. However,when the tensile axis is 121], the dislocations from the crack-tip are perfect, which will extend during their motion toward the matrix. The stress state ahead of the crack-tip and its effect on the dislocation behavior in the plastic zone were also analysed.