Processing TiRO^TM Powder for Strip Production and other Powder Consolidation Applications

Abstract:

The TiROTM process has been developed at CSIRO for the continuous direct production of Ti powder. The process has two main steps; a reaction step where the Ti is produced as very fine particles dispersed in larger particles of magnesium chloride. The MgCl₂ is separated from the Ti powder in a continuous vacuum distillation unit. The Ti product from this unit comprises a lightly sintered “biscuit” of Ti particles that can be broken up into individual particles powder with a d₅₀ around 200 μm. These particles have a unique morphology which is a function of the process.For many powder metallurgical applications TiROTM powder will require further processing to tailor its morphology for the specific application. A small sample of Ti strip has been produced from ring milled TiROTM powder by a CSIRO patented combination of direct powder rolling (DPR) followed by hot roll densification (HRD). The Ti strip was annealed and characterised in terms of microstructure and chemistry.A powder manipulation technology (PMT) has been developed to modify TIROTM particulates without the need of more expensive hydride-dehydride (HDH) or gas atomization routes to improve density, flowability, size, distribution and shape for cold spray and additive manufacturing applications.

• Periodical: Key Engineering Materials (Volume 704)
• Pages: 293-301
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.704.293
• Online since: August 2016
• Authors: Christian Doblin*, G.M. Delphine Cantin, Stefan Gulizia
• Keywords: Powder Manipulation, Ring Milling, Roll Compaction, TiRO™, Titanium Powder, Titanium Strip

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