Microstructure of V-4Cr-Ti alloy after low-temperature irradiation by ions and neutrons

[摘要] Recent interest in the application of a V-4Cr-4Ti alloy in the ITER prompted an investigation of the effects of low-to-moderate temperature irradiation (<420 degrees C) on the alloy's mechanical properties. Two sets of experiments were conducted. The effects of fast neutron irradiation to approximate to 4 dpa at 390 degrees C were investigated in the X530 experiment in the EBR-II reactor. Irradiation with single (4.5-MeV Ni2+) and dual ion beams (350-keV He+ simultaneously with 4.5-MeV Ni2+) complemented this study. TEM observations showed the formation of a high density of point-defect clusters and dislocation loops (<30 nm diameter) distributed uniformly in both types of specimens. Mechanical property testing of neutron irradiated material showed embrittlement of the alloy. The deformed microstructures were examined by TEM to determine the causes of embrittlement and revealed dislocation channels propagating through the undeformed matrix. The channels are the sole slip paths and they cause early onset of necking and loss of work-hardening. Based on a review of the available literature, suggestions are made for further research of slip localization in V-4Cr-4Ti alloys. (C) 1998 Elsevier Science B.V. All rights reserved.

[发布日期] 1998-10-01

[效力级别]  Proceedings Paper