Journal Article

Microstructure, Mechanical Properties, and Flatness of SEBM Ti-6Al-4V Sheet in As-Built and Hot Isostatically Pressed Conditions

Elambasseril, J., Tang, H. P., Liu, N., Wang, J., Qian, M., Song, C. N., Jia, L.

2017

Overview

Sheet (0.41–4.80 mm thick) or thin plate structures commonly exist in additively manufactured Ti-6Al-4V components for load-bearing applications. A batch of 64 Ti-6Al-4V sheet samples with dimensions of 210/180 mm × 42 mm × 3 mm have been additively manufactured by selective electron beam melting (SEBM). A comprehensive assessment was then made of their density, surface flatness, microstructure, and mechanical properties in both as-built and hot isostatically pressed conditions, including the influence of the hot isostatic pressing (HIP) temperature. In particular, standard long tensile (156 mm long, 2 mm thick) and fatigue (206 mm long, 2 mm thick) test sheet samples were used for assessment. As-built SEBM Ti-6Al-4V sheet samples with machined surfaces fully satisfied the minimum tensile property requirements for mill-annealed TIMETAL Ti-6Al-4V sheet products, whereas HIP-processed samples (2 mm thick) with machined surfaces achieved a high cycle fatigue (HCF) strength of 625 MPa (R = 0.06, 10 7 cycles), similar to mill-annealed Ti-6Al-4V (500–700 MPa). The unflatness was limited to 0.2 mm in both the as-built and HIP-processed conditions. A range of other revealing observations was discussed for the additive manufacturing of the Ti-6Al-4V sheet structures.

• Publisher: Springer US,Springer Nature B.V
• Subject: Additive manufacturing / Assessments / Chemistry/Food Science / Earth Sciences / Engineering / Environment / Flatness / Glass substrates / Heat treating / High cycle fatigue / Hot isostatic pressing / Mechanical properties / Microstructure / Physics / Raw materials / Sheets / Temperature / Titanium base alloys