Fabricating titanium strip

Fabricating titanium strip from novel Titanium powder production process^TM powder

The novel Titanium production process has been developed at CSIRO for the continuous direct production of titanium powder. Commercially pure titanium powder has been used for the fabrication of strip by the CSIRO direct powder rolling process.

The challenge

There has been a concerted effort by researchers world-wide to develop new generation technologies to produce low-cost titanium powders. Many of these groups, including the CSIRO novel powder production technology, are now reaching the stage of producing titanium powders on a pilot-plant scale. Of note is the fact that the titanium powders produced by the various groups can vary significantly in terms of their morphology and properties.

There is, therefore, a strong need first to develop technologies that will utilise large quantities of these powders to fabricate semi-finished or near-net shape products, and secondly to ensure that the powders from the different sources are suitable for use in the processes.

Studies have been undertaken at CSIRO to ensure that the CSIRO direct powder rolling process for fabricating strip and sheet is sufficiently versatile to process commercially pure titanium powders from a range of sources and with varied morphologies and behaviours.

Our response

In this case study we present the work done to process commercially pure powder into strip using the CSIRO direct powder rolling and hot rolling densification process.

The two CSIRO teams worked together to achieve the following:

• Process the as-received powder to a size range suitable for powder rolling;
• Perform an in-depth characterisation of the processed powder in terms of particle size distribution, morphology, density, flow behaviour and chemistry;
• Fabricate fully dense strips by the direct powder rolling and hot rolling densification process;
• Analyse the finished products.

The results

The CSIRO direct powder rolling and hot rolling densification process to fabricate strip titanium strip and sheet has been shown to be very versatile in terms of the wide range of powder morphology, properties and size distribution, that can be used successfully in the process.

The microstructure of the annealed commercially pure titanium strip made by this process and using the novel powder shows a dense and uniformly fine and equiaxed microstructure.

It is expected that the direct powder rolling process will be suitable for fabricating strip and sheet products from commercially pure CSIRO powder, as well as titanium powders from other sources.