Swedish iron powder producer Höganäs AB has invested in a new combined vacuum sintering and low pressure carburising (LPC) furnace technology at its PoP Centre, paving the way, states the company, for future cost-efficient and high quality PM component solutions.
“With the new furnace in the PoP Centre we can offer state-of-the-art technology for sintering and hardening of PM parts in pilot scale,” stated Mats Larsson, Manager PM Components – Process development. “Our intention is to work closely with customers and end-users to develop attractive PM solutions, both from a cost and functional perspective, and ultimately to help reduce time to market and grow the market for PM parts in high strength applications, with load carrying gears as the main target.”
High-strength PM applications provide a great potential to further grow the PM industry and subsequent heat treatment often plays an important role to meet application performance requirements, product quality needs and total cost targets.
Chromium-alloyed powders provide a cost-efficient way to manufacture high-performance applications. However, PM components produced from such powders cannot be surface hardened by conventional gas carburising and oil quenching. To meet the stringent requirements on quality and dimensional accuracy, an alternative is to use low pressure carburising with pressurised gas quenching.
LPC is a well proven heat treatment technology already globally applied by many OEMs. The well-known and proven advantages over traditional atmospheric carburising are manifold. For instance, the unlimited process design flexibility including high temperature sintering, the precisely monitored process control, the well-defined uniform and tailored case-depths as well as the elimination of any risk for oxidation.
Additionally, LPC results in reduced distortions during the heat treatment process and consequently improves the overall dimensional quality and tolerances of PM components. As opposed to traditional methods, the processing under vacuum vs. atmospheric, also reduces the risk of contaminants and delivers clean and bright surfaces. Reducing overall CO2 emissions and eliminating the need for secondary cleaning processes, such as shot blasting or washing etc., LPC is clearly more environmentally friendly over conventional heat treatment methods, stated Höganäs.
Due to the overall reduced process chain and reduced time for the handling of parts, the one-cycle batch vacuum sintering combined with low pressure carburising & gas quenching, leads to lower total factor cost for heat treated components.
With its new maintenance friendly furnace technology in place and through a close collaboration with ECM Technologies France, the Höganäs PoP Centre is now ready to support customers and OEMs during the development of new PM applications and processes. The new furnace concept will be presented to the PM industry community and public for the first time during the forthcoming PoP Day on the 18th of September in Höganäs, Sweden.