Science Magazine reports on a recent innovation in the world of stainless steel.
For those unaware, stainless steel was invented about 150 years ago. “It’s made by melting conventional steel – itself a combination of iron and carbon (and sometimes other metals like nickel) – and adding in chromium and molybdenum, which prevent rust and corrosion. A complex series of cooling, reheating, and rolling steps gives the material a microscopic structure with tightly packed alloy grains and thin boundaries between the grains that create a cell-like structure. When the metal is bent or stressed, planes of atoms in the grains slide past one another, sometimes causing crystalline defects to connect with each other – producing fractures. But strong boundaries can halt these defects, making the material tough, yet still flexible enough to be formed into a desired shape.”
Now, 3D printers are able to print using stainless steel – which is a big deal. Up until this point, 3D printers have worked “best with plastic and porous steel – materials too weak for hard-core applications.”
“[Researchers at Lawrence Livermore National Laboratory in California, however, have recently] come up with a way to 3D print tough and flexible stainless steel, an advance that could lead to faster and cheaper ways to make everything from rocket engines to parts for nuclear reactors and oil rigs.”
These researchers have designed “a computer-controlled process to not only create dense stainless steel layers, but to more tightly control the structure of their material from the nano to micron scale. That allows the printer to build in tiny cell wall-like structures on each scale that prevent fractures and other common problems.”
What is perhaps most impressive about this whole process is the fact the researchers used a commercially available 3D printer and laser to print with this stainless steel.
Image and Quotes Courtesy of Science Magazine