3D printing used to build high-hardness ferrous metal products

Square-nanosteel dense 3d printed partMaterials are the key to greater acceptance and use of professional 3D printing / additive manufacturing machines.

With metal materials, one of the hurdles to achieving a high hardness part using additive technology has been the tendency of the part to develop cracks during the build. NanoSteel Company, a leader in nanostructured steel materials design, claims it has overcome that hurdle with its recently announced engineered powders.

“Currently, the material options to produce highly wear-resistant parts through additive manufacturing are limited” said Harald Lemke, NanoSteel’s General Manager of Engineered Powders. “By extending the reach of steel into markets currently served by Nano-grained Tungsten Carbide-Cobalt (WC-Co), ceramics, and other non-ferrous metal matrix metal composites, we have the potential to generate cost-efficient wear parts to serve the tooling, mining, energy, and transportation industries in applications such as pumps, bearings, and cutting tools.”

Company engineers and researchers leverage the metal materials’ uniform metal matrix microstructures in the laser-sintering process. They have successfully additively built a crack-free, fully dense bulk sample.

The engineers worked with a global process development partner to optimize processing of a proprietary NanoSteel alloy with a high volume fraction of borocarbide phases. This alloy successfully produced a fully dense (99.9%) crack-free part with hardness values over 1000 HV, wear resistance comparable to conventionally manufactured M2 tool steels, and a uniform microstructure. Importantly, these properties were achieved without the need for post-processing such as hot isostatic pressing (HIP) or further heat treatment to develop metal density. By eliminating these post-processing steps, the use of these metal powders can reduce production cost and lead times.

The company is currently extending this breakthrough into more complex geometries and broadening its property sets to fully validate the market potential for 3D-printed steel components.

Leslie Langnau
llangnau@wtwhmedia.com