Production of Titanium

Abstract

A method of producing titanium semi-finished or ready-to-use products from titanium oxide powders and / or pellets is disclosed. The method produces products that are not affected adversely by levels of chlorine that have an impact on performance, particularly weldability, of products made by other methods.

Description

[0001] This application is a continuation-in-part of and claims priority to PCT application PCT / AU2005 / 000907 published in English on Jan. 5, 2006 as WO 2006 / 000025 and to Australian application no. 2004903532 filed Jun. 28, 2004, the entire contents of each are incorporated herein by reference.FIELD OF THE INVENTION [0002] The present invention relates to the production of titanium metal and titanium metal alloys. The present invention relates particularly, although by no means exclusively, to a method of producing semi-finished or ready-to-use products, such as products in sheet, bar, tube and other forms, of titanium metal (which term includes titanium alloy) from titanium oxide powders and / or pellets. BACKGROUND OF THE INVENTION [0003] Currently, the Kroll and Hunter processes are the only commercial processes for producing titanium metal. These processes include chemical reduction of TiCl4 with molten magnesium or sodium metal in a sealed reactor that has been evacuated and bac...

AI Technical Summary

Problems solved by technology

One of the disadvantages of Kroll and Hunter products formed by the direct compaction route is poor weldability when welded using arc welding technology.

The poor weldability has been attributed to high levels of chlorine, typically 1000-1500 ppm, in the products reacting with tungsten electrodes causing unstable arcs when arc welding the products.

However, the remelting route is a more expensive processing route than the direct compaction route.

However, Du Pont found that the Du Pont products had poor weldability.

As is the case with conventionally produced directly compacted Kroll products, the poor weldability of the Du Pont products has been attributed to chlorine in the products.

Du Pont has reported finding that the chlorine in the Kroll products volatilised rapidly during welding and caused a build-up of salts on tungsten welding electrodes that resulted in an unstable arc and consequently poor weldability.

Du Pont was not able to reduce the concentration of chlorine in the titanium metal or otherwise solve the poor weldability problem caused by the chlorine and consequently Du Pont did not commercialise the technology.

Specifically, the chlorine in the Kroll and Hunter products formed by the direct compaction route appears to be in a more volatile form that readily reacts with tungsten welding electrodes and makes the arcs unstable.