Effects of strain rate on dislocation for TA15 alloy during hot compressive deformation

Abstract

The effects of strain rate on the dislocation type and dislocation configure of TA15 alloy were investigated. The experimental results show that the operating dislocation type changes from $\bar c$ type to $\bar c$ and $\bar a + \bar c$ type with increasing strain rate under the deformation condition of 900 °C, 60% strain. Under the condition of 900 °C, 60% strain and 0.001/s strain rate, lots of orientate dislocation cellular configurations and sub-grains, many dislocations pile up before sub boundary. When the strain rate increases to 0.1/s, some dislocations exhibit curved and dislocation tangles and pile-ups can be found, suggesting more dislocations and much stronger interactions among dislocations.

Keywords

TA15 alloy / hot deformation / dislocation type / dislocation configuration / strain rate

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