New laser manufacturing technique enables complex ceramic-metal parts
Researchers have demonstrated how laser-based 3D printing can produce cemented carbides—ultra-hard materials used in cutting tools and industrial equipment—with intricate shapes impossible to make with traditional methods. The breakthrough could expand markets for these high-value components and reduce manufacturing waste by enabling near-complete finished parts directly from the printer.
Originaltitel: Laser-Based Solidification of Cermets/Cemented Carbides: Processing-Microstructure-Property Relationships
Lasersyntesade hårdmetaller öppnar vägen för komplexa komponenter utan dagens begränsningar. Traditionell pulvermetallurgi producerar hårdmetaller (cermetser) med begränsade former och inducerade defekter, medan direkt smältning via laser möjliggör nätnära former och intrikata geometrier i ett stegs process. Luleå tekniska universitet tillsammans med forskargrupper från Tallinn och Guangzhou granskar hur laserpulverbäddsfusion och riktad energideposition formar mikrostruktur och mekaniska egenskaper i dessa material. Fördelen är betydande: komponenter ontstår utan omfattande efterbearbetning, vilket minskar produktionskostnader och öppnar för funktionaliteter tidigare omöjliga att tillverka. För leverantörer av hårdmetallverktyg och komplexa maskindelar blir detta verktyget för att konkurrera på design och lead time. Tekniken befinner sig i utvecklingsfasen — kommersialisering inom två till tre år rimlig tidshorisont för tidiga adoptörer.
<p>Cermets/Cemented carbides belong to the class of materials that reap the properties of both ceramics and metallic phases and are generally fabricated using powder metallurgical techniques. Fabrication through the conventional solidification route is not feasible due to the high melting points of ceramics. The size and shape of cermets produced by powder metallurgical techniques are rather restricted, and the presence of induced defects will depend on the process conditions. To widen the applications of the cermets/cemented carbides and to fabricate intricate parts with added functionalities, novel additive manufacturing techniques (AM) may be employed for the fabrication of cermets. Since the AM process takes place in a layer-by-layer fashion, the fabrication of cermets can lead to the production of parts with intricate and complex shapes without boundaries. Laser powder-bed fusion process and directed energy deposition are two major laser-based techniques that can fabricate cermets/cemented carbides using the solidification route. One advantage of using solidification-based AM technology is that it can produce near-dense and near-net-shaped components without the need for further post-processing. This review highlights recent advancements in the laser-based solidification of cermets and cemented carbide, addressing their microstructural features, resulting properties, and the challenges inherent to these AM processes. </p>