Optimizing Bulk Metallic Glasses for Robust, Highly Wear‐Resistant Gears

Despite their promising mechanical properties and ability to be manufactured like plastics, bulk metallic glasses (BMGs) are slow to emerge as a structural engineering material. Because BMGs properties are highly correlated with processing, it is necessary to test them in a relevant engineering application. In the current work, CuZr‐based BMGs are developed with excellent wear performance when used as gears. It is shown that in order to optimize the wear performance of these gears, toughness should be maximized. This contrasts the conventional design strategy, where wear performance increases with increasing hardness. Finally, a new low‐cost manufacturing method for casting net‐shaped macroscale gears is developed. A new method for casting bulk metallic glass (BMG) gears is presented By running gears, the authors find that when toughness is considered as the design parameter, not hardness, highly wear‐resistant gears can be developed. This may lead to an entirely new class of high‐performance gearboxes.