Recent innovations in laser additive manufacturing of titanium alloys

Abstract

Titanium (Ti) alloys are widely used in frontier fields like aerospace and biomedical engineering. Laser additive manufacturing (LAM), as an innovative technology, is the key driver for the development of Ti alloys. Despite the significant advancements in LAM of Ti alloys, there remain challenges that need further research and development efforts. To recap the potential of LAM high-performance Ti alloy, this article systematically reviews LAM Ti alloys with up-to-date information on process, materials, and properties. Several feasible solutions to advance LAM Ti alloys were reviewed, including intelligent process parameters optimization, LAM process innovation with auxiliary fields and novel Ti alloys customization for LAM. The auxiliary energy fields (e.g., thermal, acoustic, mechanical deformation and magnetic fields) that can be applied during LAM Ti alloys affect the melt pool dynamics and solidification behaviour, altering microstructures and mechanical performances. Different kinds of novel Ti alloys customized for LAM, like peritectic α-Ti, eutectoid (α+β)-Ti, hybrid (α+β)-Ti, isomorphous β-Ti and eutectic β-Ti alloys are reviewed in detail. Furthermore, machine learning in accelerating the LAM process optimization and new materials development is also outlooked. The review summarizes the material properties and performance envelops and benchmarks the research achievements in LAM of Ti alloys. In addition, the perspectives and further trends in LAM of Ti alloys are also highlighted.

Advances and challenges in direct additive manufacturing of dense ceramic oxides

“…Similar as L-PBF, L-DED utilizes a high-energy laser beam to melt raw powders under inert atmosphere, and achieves metallurgical bonding between adjacent scan lines or layers. However, L-DED employs a synchronous powder feeding system, in which energy delivery and material deposition are focused on the same region, allowing for a better control of material feed [53,54]. The working principle of L-DED is illustrated in figure 3(b): a laser beam is directed onto the substrate surface to locally form a molten pool, and the raw powder is simultaneously transported by inert gas and delivered to the stable melt region through lateral or coaxial powder feeding nozzles.…”