Exploitation of field assisted sintering technology (FAST) for titanium alloys

Abstract

Field assisted sintering technology (FAST), also known as spark plasma sintering (SPS), is increasingly utilised to process powders/particulates of engineering alloys and metal-based composite materials. FAST is currently extensively used at laboratory scale by research institutes and universities as a rapid and cost‑effective process to consolidate powders. This includes investigating new alloy compositions and material combinations, improving established materials’ properties, and consolidating materials considered challenging/impossible through conventional sintering techniques. FAST is gaining traction for industrial applications with possible benefits as an alternative to hot isostatic pressing or conventional melt-wrought processing. FAST preform complexity is improving and near-net-shape components are becoming a possibility. Demonstrator components for the aerospace and automotive sectors, including aeroengine blades, brake callipers and rocker arms, have been produced from titanium alloy powders. FAST has also been demonstrated as an effective intermediate step for consolidating a range of feedstocks, including recycled materials, into shaped billets that can be further processed to refine shape and/or properties. Hybrid processes such as FAST‑forge and FAST‑DB have been developed that can produce affordable titanium components with forged properties. This paper presents the current status, emerging developments, and challenges of FAST for titanium-based powders and particulates.