A New Bronze-Steel Alloy Has Been Developed Thanks to 3D Printing

A group of researchers at the Skolkovo Institute of Science and Technology, or Skoltech, say they have developed a new bronze-steel alloy using additive manufacturing. They turned to direct laser deposition to produce different parts composed of these two metals, a first for the market. Two techniques were used: in the first case, a mixture of the two metals was made before depositing the layers; in the second, layers of bronze were deposited alternately with those of steel. According to the researchers, this work could be particularly interesting for the aerospace industry, especially in the construction of combustion chambers for aircraft and rockets.

It is not uncommon to combine two materials to take advantage of the best of their respective properties – for example this is the direction in which composite 3D printing is rapidly developing. In this particular case, the two were chosen thanks to their ability to complement each other. Bronze is known for its corrosion resistance, good electrical conductivity and high wear resistance. Steel, on the other hand, is resistant to breakage and impact, electrical deformation and has high hardness. This project is a first of its kind as it has created a bronze-steel alloy that was previously unknown to material science. And it is all thanks to additive manufacturing.

A 3D printed part that was made to test the mechnical properties of the new bronze-steel alloy (photo credits: Konstantin Makarenko/Skoltech

In concrete terms, the researchers used direct laser deposition (which works like directed energy deposition) to develop their project. First, they had to create an almost homogeneous alloy by mixing the two materials in a uniform manner. This alloy was then used by the machine to design several test parts. The other technique was to print “sandwich” parts, i.e. composed of layers of bronze and steel, each 0.25 millimeters thick. The researchers explain that they varied the amount of bronze each time – from 25 to 50% – while the steel content remained the same.