npj Materials Degradation

From the DeLorean to skyscrapers, stainless steel is known for its exceptional strength. But exposure to certain elements, such as seawater, can compromise it. Grinding the surface of stainless steel has long been known to reduce its corrosion resistance, and now researchers at Tohoku University have discovered why, potentially opening the door to new ways to mitigate the problem.

Old trees are learning new tricks with the advent of composite materials. Made of biodegradable polymers and the waste bark of the Yakushima Jisugi tree, the green composite was developed by a research team at Tohoku University. When assessing the material, they found that simply testing its mechanical strength — in this case, its tensile strength or ability to resist pulling —could reliably predict the biodegradation process. Traditionally, in processes that are costly in time and money, scientists chemically test how much of a material remains after time has passed. Shifting assessment focus to how a material continues to safely function during the biodegradation process, the team said, could help better inform practical use of such products.