EXPLOITING HALL-PETCH STRENGTHENING FOR SUSTAINABILITY

Sustainable engineering embraces conservation of materials and energy. Nanomaterials, and in particular nano-metal materials, can play a significant role in reducing the negative impact that we have on our planet through the exploitation of properties derived from the Hall-Petch relationship. Designers can reduce section mass in moving parts thus enhancing energy efficiency and reducing greenhouse gas emissions (e.g., MetaFuse (TM) nanometal-polymer hybrids for lightweight automotive components). They can also design for longer product life-cycles, thus reducing scrap rates and landfill requirements. Moreover, Hall-Petch strengthening of environmentally benign alloy systems can lead to the replacement of incumbent toxic materials and processes (e.g., nano CoP coatings as a replacement for hexavalent chromium plating; nano-copper coaxial composite wire for the replacement of toxic Beryllium alloys). In this paper, an overview is provided of these "sustainable" nanomaterials which are rapidly finding market acceptance.