From medicine to space, HPA is a high-tech material, with a growing list of applications

3 Nov 2015

We’re very excited about the potential applications for our high-purity alumina (HPA), which we’ll be producing from our wholly owned deposit of 65 million tonnes of aluminous clay (kaolin) at Meckering in Western Australia, and our planned processing plant in southern Malaysia – which we expect to start constructing early in 2016.

The 4,000 tonnes of 99.99% (4N) HPA a year that we aim to produce in Malaysia will have a variety of uses. In an earlier blog post, we looked at the massive opportunity to supply HPA into the ‘sapphire’ glass market, which supplies scratch and breakage-resistant artificial glass to smartphone markers. We’ll certainly be aiming at that market – which is potentially revolutionary – but this post will look at the other uses for HPA. 

At the moment, the global HPA market is mainly divided into four segments: LED (light-emitting diode) applications, semiconductors, phosphor applications, and ‘other’ uses. Here’s a pie-chart of the current market: 

Currently, the biggest use of HPA is in high-brightness LED lighting, a semiconductor device that converts electricity into light. This market accounts for 55% of global HPA demand. LED lighting is widely used for advertisement lighting, displays, automobile headlights, home illumination and especially the backlights in mobile phones.

Manufacturing LED lighting requires sapphire substrates, and currently there’s no substitute for HPA in the manufacture of these substrates, consequently demand is expected to remain a strong for HPA in this application.

The next largest market segment is semiconductors, in which alumina is used in the sapphire wafers required for the manufacture of semiconductors. These wafers are very widely used in the electronics industry. This accounts for 22% of current HPA demand.

Then there are the phosphor applications, which represent 16% of the market. This mainly refers to plasma display panels in TVs and computer screens. HPA is one of the materials that controls the characteristics of phosphors, and has a very important position in this application. HPA phosphors are used in next-generation displays, and it’s expected that this demand will only broaden in the future.

Let there be light

‘Other’ uses take up 7% of the HPA market. This category covers a very wide range of uses. For example, translucent HPA ceramics are used in sodium lamps, which use an electrical gas discharge in sodium vapour to create light: the HPA ceramics are used to make the luminous tubes, because they resist reaction with the high-temperature sodium vapour. Sodium lamps are higher in efficiency and luminance compared with incandescent and fluorescent lamps: they are widely used to illuminate exterior spaces such as roads, streets and public spaces, as well as factories and sports facilities. They are also used as a light source in horticulture.

Then there are the medical uses, of which the main one is orthopaedic implants – in particular, artificial hip-joint ‘balls’ – and tooth implants. HPA bio-ceramics are very well-suited to these tasks, being bio-inert and showing high resistance against corrosion in the human body: they are also wear-resistant, with high compression strength and fatigue strength. This usage of HPA is in these applications is also expected grow.

HPA’s low-friction and high wear-resistance, thermal and electrical insulating ability and broad chemical compatibility also finds it a place in military and space-based uses, in engine components, heat shields, electrical insulators, pump and valve components, as well as satellite and radar electronics systems. Again, the use of HPA in such applications should also grow.

Interestingly, HPA is also used in the manufacturing of lithium-ion batteries, automotive sensors, high-tech lasers and video and computer equipment, and as an abrasive for the polishing of optic and electronic equipment. In addition to its chemical resistance and heat resistance properties, HPA is used in ultra-filtration and gas separation membranes.

Considering it starts out as clay, HPA is an amazingly versatile material – which is why we’re so excited about bringing a major new source of it on-stream to supply a market where an explosion of demand is predicted.