Recent research explores additive manufacturing of hard metal components
A research team from Hiroshima University has developed an additive manufacturing approach for tungsten carbide–cobalt cemented carbides, a core material for cutting tools, drawing dies and high-wear components.
The study, published online in December 2025 in the International Journal of Refractory Metals and Hard Materials, examines a hot-wire laser irradiation process designed to reduce raw material waste while preserving the hardness and structural integrity required in industrial tooling.
Cemented carbides are conventionally produced through powder metallurgy, combining tungsten carbide and cobalt powders under high pressure followed by sintering. Although this route ensures high wear resistance, it requires significant volumes of costly raw materials.
Hot-wire laser process for hard metal production
The proposed process is based on additive manufacturing using hot-wire laser irradiation, where a laser beam and a preheated filler wire are applied simultaneously to increase deposition efficiency and control heat input.
Instead of fully melting the material, the researchers applied controlled softening to limit tungsten carbide decomposition and excessive grain growth — both critical to tool life and wear resistance.
After testing different fabrication strategies, the introduction of a nickel-based alloy intermediate layer and optimized temperature control enabled the production of stable, defect-free structures.
Hardness above 1400 HV
Under optimized conditions, the additively manufactured cemented carbides achieved hardness values above 1400 HV, comparable to conventionally produced grades.
“The approach of forming metal materials by softening them rather than fully melting them is novel, and it has the potential to be applied not only to cemented carbides, but also to other materials,” said Assistant Professor Keita Marumoto.
For cutting tool manufacturers and die producers, maintaining this hardness level is essential. Any alternative production method must match the wear resistance and mechanical strength of powder metallurgy components.
Further work will focus on crack control and more complex geometries. Although still at a research stage, the development outlines a potential pathway for producing cemented carbides with lower material consumption and greater design flexibility — particularly relevant at a time when tungsten prices are at their highest levels in more than a decade.
If industrialized, the process could support tooling and equipment manufacturers in addressing raw material cost pressures while expanding manufacturing options for wear-critical components.
Full details of the study are outlined in the official Hiroshima University release .
