On the absence of shear cracking and grain boundary cavitation in secondary tensile regions of Ti–6Al–4V–0.1B alloy during hot (α + β)-compression

Abstract

Deformation instabilities, such as shear cracking and grain boundary cavitation, which are observed in the secondary tensile region of Ti–6Al–4V alloy during compressive deformation in the (α + β)-phase field, do not form in Ti–6Al–4V–0.1B alloy when processed under the same conditions. This has been attributed to the microstructural modifications, e.g. the absence of grain boundary α and adjacent grain boundary retained β layers and a lower proportion of 90^o-misoriented α-colonies that occur with boron addition.

Keywords:

• Ti–6Al–4V–0.1B alloy
• hot compression
• deformation instability
• microstructure
• electron microscopy
• EBSD

Acknowledgements

We gratefully acknowledge Drs. D.B. Miracle (AFRL) and S. Tamirisakandala (FMW Composites, USA) for providing the as-cast alloys. We also thank Shri S. Sashidhara for his kind help in the hot compression experiments.

Notes

1. DARTEC® Zwick/Roell GmbH Group, Germany.

2. QUANTA 200, FEI, The Netherlands.

3. EDAX, AMETEK Inc., USA.

4. JXA-8530F, JEOL, Japan.

5. Struers® Lectropol-5, Struers A/S, Germany.