Ti6Al4V alloy fabricated by gelcasting based on low-oxygen gel system using hydride-dehydride titanium alloy powders

Oxygen and carbon impurity residues and low density are the main issues for Ti gelcasting. To overcome these difficulties, this study develops a low-oxygen isoprene (Ip)/polyvinyl butyral (PVB) gel system to achieve Ti gelcasting using hydride-dihydride (HDH) Ti6Al4V powder. Slurries with 48 vol% solid loading content are employed to achieve moulding followed by cold isostatic pressing. During gelcasting, powder particles are held in place by the cross-linking of Ip monomer with PVB as adhesive to maintain shape. After sintering, nearly fully dense (4.38 g/cm(3)) Ti6Al4V alloys with low interstitial contamination (O: 0.356 wt%, C: 0.14 wt%) are successfully fabricated. The samples exhibit acceptable mechanical performance, with ultimate tensile strength of 1062 MPa, yield strength of 987 MPa, and elongation of 8.75%. Typical plastic fracture with river patterns is observed, which is distinctly different from that of HEMA based sample. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

This study successfully achieved Ti gelcasting using a low-oxygen isoprene/polyvinyl butyral gel system, developing nearly fully dense Ti6Al4V alloys with low contamination levels and acceptable mechanical performance.