Direct metal laser sintering of Ti-6Al-4V parts with reused powder

Abstract

Ti-6Al-4V alloy is characterised by having excellent mechanical properties and corrosion resistance combined with low specific weight and biocompatibility. This material is ideal for many high-performance engineering applications. It is increasingly used in additive manufacturing (AM) thanks to the possibility of producing very complex lightweight structures, often not achievable with conventional manufacturing techniques, as well as to easily customise products according to specific customer requirements. In powder bed fusion (PBF) processes, only a small percentage of the powder is actually melted and solidified to achieve the final part while most is left after the build. Since the surface morphology and chemistry, the shape and size distribution of the un-melted particles are inevitably modified during the process, and this may affect the resulting properties of the final products, many companies tend to use virgin powders for AM builds to keep compliance with manufacturing requirements and minimise risk. From both an economic and environmental point of view, it results crucial to develop recycling methods to reuse the metal powder as many times as possible while maintaining compliance with manufacturing standards. In this work, the effect of Ti-6Al-4V powder reuse on the evolution of powder characteristics and mechanical properties of final products additively manufactured is investigated through a systematic approach based on design of experiments.

The microstructure, mechanical and electrochemical properties of 3D printed alloys with reusing powders

“…In a different study 13 , the porosity was found to increase in the first few cycles of reusing the powder, but it later decreased. In other studies conducted on Ti6Al4V, powder recycling was reported to have no influence on the porosity 12 and mechanical properties 23 of the final object.…”

Nanoscale Chemical Surface Analyses of Recycled Powder for Direct Metal Powder Bed Fusion Ti-6Al-4V Root Analog Dental Implant: An X-ray Photoelectron Spectroscopy Study

“…Ti-6Al-4V alloy is a well-known material for many biomedical applications due to its excellent mechanical properties, good corrosion resistance, biocompatibility, and light-specific weight [ 1 , 2 , 3 ]. Ti-6Al-4V is a double-phase (α + β) titanium alloy.…”