Currently, steel alloy powder produced for additive manufacturing has a relatively small market share. A new development from advanced materials company NanoSteel could change all that, says company VP Harald Lemke.

Rhode Island, US-based NanoSteel focuses on designing and commercializing a range of new steel sheets and powders. Its speciality in 3D printing is a range of steel alloy powders for a variety of applications requiring components that are strong, hard wearing or abrasion resistant. Now the company has continued to expand its focus within the 3D printing arena with the launch of a steel powder for laser powder bed fusion (LPBF) additive manufacturing (AM).

The first LPBF material now available from the company is BLDRmetal L-40, designed to enable the 3D printing of high-hardness components. BLDRmetal L-40 is a case-hardening steel powder which can create parts featuring a surface hardness of over 70 HRC, high core ductility with over 10% elongation, and room temperature printability, according to the company. Importantly, the powder can be printed using standard commercial equipment.

NanoSteel's initial customer case study shows that the steel powder has a superior performance compared to M300 maraging steel and is an alternative to difficult-to-print tool steels such as H13. BLDRmetal L-40 is designed to be used for components including tools, dies, bearings and gears.

Complicated geometry

3D printing has become economic today for applications that can take advantage of the geometric freedom that the process provides. The benefits of additional part complexity can include lightweighting, part-count consolidation and supply chain process improvements. NanoSteel demonstrated the value of additional complexity in their first case study, where BLDRmetal L-40 powder was used to manufacture a complex roll thread die set for customer Perfect Lock Bolt America Inc.

In cooperation with production partner CFK GmbH of Kriftel, Germany, and others, the two companies tailored the printing process and parameters to meet dimensional and surface tolerances. Concurrently, the roll thread dies, measuring approximately 20 cm (∼8 inches), were optimized in several iterations. As well as this, NanoSteel identified the post-production process to raise the surface hardness to ∼70 HRC and provide a surface finish with Ra of approximately 2–3 μm.

This article appeared in the November–December 2017 issue of Metal Powder Report.