About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
|
Symposium
|
Additive Manufacturing of Titanium-based Materials: Processing, Microstructure and Material Properties
|
Presentation Title |
Microstructure Mechanical Property Relationship for Post Heat-treated Electron Beam Melted Ti-6Al-4V Alloy |
Author(s) |
Amit Kumar Singh, Anish Ranjan, Sushil Mishra |
On-Site Speaker (Planned) |
Amit Kumar Singh |
Abstract Scope |
Powder bed Electron Beam Melting of Ti-6Al-4V possesses better ultimate tensile strength than the conventional mill-annealed Ti-6Al-4V. The changes in microstructure, tensile, and fatigue crack growth rates were observed in the heat-treated samples below and above β transus temperature for one hour of residence time followed by water and furnace cooling. Heat treatment below β transus temperature do not erase the signature of epitaxial growth during re-melting of subsequent layers in the EBM process. Whereas, the heat treatment above β transus temperature erases the footprint of additive manufacturing, and epitaxial columnar grain growth of prior β grans is converted into coarse α+β phase and the structure is homogenous normal to building and transverse directions and hence the structure is similar to conventional Ti-6Al-4V. Very fine grains decorated with nano-size β phase in as build microstructure possess better mechanical strength, ductility, and fatigue crack growth resistance than heat-treated samples. |