Synthesis and Characterization of Nanodiamond Reinforced Copper Composites for Use in Cold Spray

LT Matthew Englehart, USN

The use of cold-spray (CS) is becoming a highly sought after means of material repair, coating, and fabrication. It is considered to be environmentally friendly and an often safer form of material deposition due to the relatively low temperatures compared to tradition techniques such as welding. The cold spray process utilizes a unique method of material adhesion in order to achieve a solid state deposition using metals and composites where particular applications are temperature sensitive. High-energy ball-milling and planetary ball-milling were employed for the ex situ strengthening of copper (Cu) with nanodiamond (ND). Cu-ND composites with 10 percent ND by weight were synthesized to adjust their respective mechanical properties. For each milling process, the only variable changed was milling time to investigate its effects. After obtaining quantitative values to the altered mechanical properties, the powders were consolidated using cold spray deposition to create a ND reinforced Cu coating. This study aims to advance research of Cu-ND composites for the benefits of using CS application of copper to produce coatings which increase strength and corrosion characteristics while reducing cost by increasing the deposition efficiency of the spray. Future use of this process could potentially benefit the military by increasing the strength and corrosive properties of specific surfaces where application of the coating is temperature sensitive.