A branch of the US Army Research Laboratory have been developing a Powder Bed Fusion 3D printing process using a steel alloy powder which could be used to produce and replace parts for maintenance and servicing of battlefield equipment. The 3D printed product is said to be 50% stronger than commercially available equivalents.

The material used in the process is AF-96 metal alloy which was originally developed by the US air force and is a low-cost high-strength alloy used to make ‘bunker-busting’ munitions. Instead of transporting truckloads of spares between various warehouses and the place where they are needed, you would only need a sack of alloy powder, the 3D printer and a memory stick containing .STL files for every part that’s likely to fail. The printer employs a Powder Bed Fusion process using a laser to melt a layer of the powder to the desired pattern. This process is layered like extrusion printers by applying new layers of powder until the part is complete.

It has its limitations

The method is particularly suitable for areas where the printed part does not have to meet precision requirements with regard to dimensional accuracy or surface finish. The printed part has the feel of an item made of forged steel and its load capacity is extraordinarily high for a printed part.
Compared to existing solutions, the new material is about 50% stronger. A long process of trials and testing are necessary before the process is certified for military use. The researchers have already successfully printed several impeller fans for the M1 Abrams tank cooling system and have shown that they work in practice.