Engineers from the max Planck Institute in Dusseldorf and the Institute for laser technology in Aachen have combined ancient and modern technology by developing a method of 3D printing from Damascus steel.
Typical of the legendary steel structure with alternating soft and hard layers have been achieved using cyclic heating and cooling.
Damascus steel (or Damascus) is a type of steel with visible discontinuities on the steel surface, often in the form of patterns. It was given to combining several kinds of steel with different carbon content are repeatedly formed and hot with each other. Controlling the carbon content, the blacksmith could create a durable, flexible steel for the core of the sword, and then to weld tough and hard steel for the edge of the blade.
Today Damascus steel is typically made from two different grades of steel alloy, but it’s still a craft in which more art than science. But the engineers managed to move the Damascus steel in the twenty-first century using 3D printers and lasers.
Instead of using two different materials and processing them to form a new alloy, the new technology uses only one material – the alloy powder of iron, Nickel and titanium. It is applied layer by layer with a laser that melts the powder to form a desired shape.
This is a basic 3D printing for metal, but new technology is characterized in that the laser is used to change the crystalline structure of the metal with the formation of alternating layers of hard plastic and steel – a kind of printed damask steel.
“We managed to change the microstructure of the individual layers during 3D printing to the final component had the desired properties without a subsequent heat treatment of steel,” says Philip Kuersteiner, one of the authors of the new work.
As you add each layer the metal is allowed to cool to a temperature below 195 ° C. This enables to form a soft layer. To obtain a hard layer on top, adds a second layer of metal that is cooled, and the laser begins to work, changing the structure and hardening it. The result is steel, which is a combination of strength and plasticity.
“Until now, common practice was the use of known alloys in 3D printing.??However, many such alloys are not very suitable for the new technology. Our approach is to develop new alloys that can exploit the full potential of 3D printing,” says Kuersteiner.