Directionally-Dependent Mechanical Properties of Ti6Al4V Manufactured by Electron Beam Melting (EBM) and Selective Laser Melting (SLM).

Tim Pasang,Yuji Sato,Celine Turangi,Cho-Pei Jiang,Wojciech Z Misiolek,Ben Jackson,Mike Fry,Yuan Tao,Jia-Chang Wang,Omri Yannay,Benny Tavlovich,Masahiro Tsukamoto

doi:10.3390/ma14133603

Abstract

An investigation of mechanical properties of Ti6Al4V produced by additive manufacturing (AM) in the as-printed condition have been conducted and compared with wrought alloys. The AM samples were built by Selective Laser Melting (SLM) and Electron Beam Melting (EBM) in 0°, 45° and 90°—relative to horizontal direction. Similarly, the wrought samples were also cut and tested in the same directions relative to the plate rolling direction. The microstructures of the samples were significantly different on all samples. α′ martensite was observed on the SLM, acicular α on EBM and combination of both on the wrought alloy. EBM samples had higher surface roughness (Ra) compared with both SLM and wrought alloy. SLM samples were comparatively harder than wrought alloy and EBM. Tensile strength of the wrought alloy was higher in all directions except for 45°, where SLM samples showed higher strength than both EBM and wrought alloy on that direction. The ductility of the wrought alloy was consistently higher than both SLM and EBM indicated by clear necking feature on the wrought alloy samples. Dimples were observed on all fracture surfaces.

Highlights

Additive manufacturing (AM) has gained huge popularity in the last decade or so
It presents a comparison of surface roughness, microsctructures and mechanical properties of samples manufactured by electron beam melting (EBM) and selective laser melting (SLM) built in the 0◦, 45◦ and 90◦ in the as-printed conditions, compared with those of wrought alloys in three different directions
Both the SLM and EBM were in the as-printed condition, while the wrought alloy was in the as-received condition

Summary

Introduction

Additive manufacturing (AM) has gained huge popularity in the last decade or so. Its ability to produce complex shapes, reduce the number of parts, reduce the material waste, etc. have been the main drive of this technology. SLM produces samples with higher strength (lower ductility), higher fatigue strength compared to EBM products due to the faster cooling rates on the former [24,25,26,27,28]. Gao et al reported that the higher yield and tensile strengths of samples produced by SLM compared with those of EBM due to the presence of α martensite on the former.

Results

Conclusion