Erosive Wear Resistance of Nature-inspired Flexible Materials

Materials providing high resistance to wear and macro-deformations or impacts are needed for many applications (material handling hoses or flexible ducting systems, snow plow cutting edges, human joint prostheses, Mars rover wheels, etc.). Production of wear-resistant materials using the promising approach of additive manufacturing (AM) is currently of great interest. Specific nature-inspired or -mimicking AM-printed topographies are allowing the reduction and stabilization of friction coefficients and improved tribo-properties. Moreover, they have multifaceted features such as self-healing, supply of lubricants, improved adhesion, etc. The materials, inspired by mole pelts (fur) and fish, snake and pangolin scales, combine three to four phases, namely hard reinforcement, a skeleton supporting the reinforcement and elastic rubber between elements of the skeleton for flexibility and/or damping of impacts. Brazing can be used to fix the reinforcement if required. Three types of composite materials [CBN brazed into steel pipes/rubber, diamond-coated steel wire/rubber and Ti6Al4V (with or without surface treatment) scales/rubber] were produced and tested by a centrifugal erosion device at 30, 50 and 80 m/s speeds and 30º impact angle. The wear rates were determined, and the discussion of the wear mechanisms is supported by optical, scanning electron microscope and 3D profilometry images.