September 12, 2022
Global Tungsten & Powders? Many of you may have already heard of the company that joined the Plansee Group as a supplier of tungsten and tungsten carbide powder in 2008. But what is the story behind GTP and its powders?
In the largest plant in Towanda, Pennsylvania, GTP produces raw materials for carbide production, among other things. More than 500 employees in the USA manufacture not just ammonium paratungstate (APT), tungsten oxide (WOx), tungsten metal powder (WMP), tungsten carbide (WC) and ready-to- press powder (RTP), but also semi-finished products and components made of tungsten and tungsten alloys. More than 20 employees in the Research and Development department work to ensure that GTP will always be one step ahead of the competition in the future.
The route from the ore in the tungsten mines to the valuable tungsten powder for further processing is a long one. “The tungsten goes through the longest stage – from ground ore or scrap to powder – here in Towanda. We are actually a huge chemical factory in which a competent team prepares the tungsten for further processing in countless individual chemical processes,” explains Bernard Legrand, Director of Operations at GTP. There are optimized types of powder for different applications. In addition to tungsten carbide, GTP also produces RTP, i.e. ready-to-press powders, which can be used as the starting material for the manufacturing of solid carbide tools, wear parts, and other precision components. The powders supplied by GTP are already alloyed so they can be used directly in the production of indexable inserts, for example. It is as easy as press, sinter, done!
GTP Powders has been part of the CERATIZIT Group since July 2021 and forms its own division. The plants in Bruntal, Czech Republic, and Niederkorn, Luxembourg process the tungsten oxide from Towanda into tungsten carbide for CERATIZIT and tungsten metal powder for Plansee HPM (High-Performance Materials). CERATIZIT’s Stadler Metalle in Turkheim, Germany and Tikomet Oy in Jyvaskyla, Finland focus on recycling. Stadler Metalle specializes in the trade of secondary raw materials, while Tikomet is responsible for recycling hard metal scrap into tungsten carbide-cobalt powder.
The global market for tungsten is clearly staked out and is largely served by Chinese suppliers. More than 80% of the near-surface tungsten ore deposits that can be mined with relatively little effort are located in China. “Only these deposits can be exploited economically, otherwise the costs of mining would increase immeasurably,” says Eric Rowe, Director of Raw Materials Sourcing & Planning. Nevertheless, it has always been important to GTP to ensure a conflict-free supply of raw materials. In 2013, GTP was the first tungsten smelter in the world to be recognized as a “Conflict Free Smelter” and today meets the OECD Due Diligence Guidelines for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas. “We are committed to ensuring that all our raw materials are sourced responsibly and do not contribute to armed conflict, child labor, human rights abuses or other serious crimes,” Eric Rowe adds. GTP, together with the Plansee Group secured long-running, sustainable sources to cover all raw material needs.
Anyone who has ever experienced the roads in Finland during winter knows that you can’t get by with normal tires on your car. So, some savvy Finns came up with the idea of upgrading their tires with spikes. Because normal materials would wear out far too quickly, tungsten spikes are used in the rubber compound of the tires. They are cheap and can be made from recycled materials, such as those produced by Tikomet Oy. The company, with 46 employees, specializes in recycling scrap carbide for a wide range of applications, including to manufacture these spikes. Using state-of-the-art technology, these secondary raw materials are processed back into tungsten carbide-cobalt powder in the zinc process.
In the zinc process, hard metal scrap is charged with pieces of zinc in graphite crucibles and processed in a special furnace. The technology is based on the fact that the cobalt reacts with the liquid zinc that diffuses in. As a result of this reaction, intermetallic phases with high volumetric expansion are formed. The scrap puffs up and breaks up into thin layers. What remains is a porous mass of tungsten carbide and cobalt. The zinc, on the other hand, is vaporized at high temperatures and almost completely recovered. The porous mass is then crushed into powder. This is followed by a fine grinding process and the production of a homogeneous batch in a batch mixer. In contrast to the chemical process, there is no chemical conversion of the tungsten carbide and the binder metal in the zinc process. This means that the original carbide grain size of the tungsten carbide does not change, and the cobalt can also be recovered.
This recycling process works with all types of worn carbide parts and accounts for a substantial portion of the supply of tungsten raw materials. The chemical plant in Towanda also processes all types of scrap containing tungsten by means of calcination and refining – regardless of whether it is unsorted hard scrap, powdered scrap or soft scrap. Even grinding sludge is recycled. For the best results, however, the extensive experience that GTP has gained through decades of continuous process optimization is important. Sustainability has not just been on the agenda at CERATIZIT since yesterday!
Chemical recycling is also out in front when it comes to sustainability and reducing the carbon footprint. Compared to production from tungsten ore, it reduces emissions by a factor of 4. The CO2 emissions from the zinc process, on the other hand, are an order of magnitude lower than the emissions from chemical recycling, even when using environmentally harmful energy sources. With green energy, the zinc process is almost carbon neutral. With Stadler Metalle, which has been 100% part of CERATIZIT since 1 March 2022, CERATIZIT is the only western carbide manufacturer with its own integrated source of secondary raw materials, giving it an important competitive advantage.
One thing is clear: the demand for tungsten will continue to grow in the coming years. GTP is therefore doing everything in its power to continue to secure the supply of raw materials. “The numerous measures – from collaboration with profitable mines to continuously increasing the recycled material quota – bolster our independence while strengthening the market positioning and sustainability values of the entire Group. Our main task is to always ensure a secure and competitive tungsten supply chain for the Plansee Group,” explains Melissa Albeck, who, in addition to her role as President and CEO of GTP, is also a Member of the Executive Board of CERATIZIT.