Surface wear describes the process of material loss when two surfaces come into contact with each other. It has significant economic, social and health consequences – just think of the fine particles emitted by moving vehicles. There are several wear mechanisms, yet the adhesive type is most common. It takes place when two surfaces – such as two pieces of the same metal – rub against one another and adhere. Researchers at EPFL’s Computational Solid Mechanics Laboratory (LSMS) have numerically simulated for the first time how surface roughness changes over time, and their results are in line with experimental results. What sets their simulations apart is their duration: using a method developed at EPFL, the LSMS researchers were able to simulate these mechanisms over an extended period of time. In other words, they managed to capture the entire process – from the initial geometry to the final fractal geometry. Their findings were published in Nature Communications.
Following this work, the LSMS researchers have been extending such approach to the case of surfaces that exhibit low interfacial adhesion, for example, after a treatment that reduces their corrosion (passivation). This case has important implications, as surfaces for engineering applications are often treated to reduce friction and wear.