The effectiveness of the reinforcement of carbon nanotubes (CNTs) in most composites so far developed has been disappointing. This is mainly attributed to poor interfacial bonding and poor alignment as well as CNTs' waviness in the composite. Metallic matrix composites can be successfully developed to meet strength and anti wear applications where strength to mass ratio is not strict as in the space applications related. PI plans to study the novel brush plating for the fabrication of CNTs reinforced metallic composite coatings. The electrolyte ("ink") consisting CNTs and the metallic ions will be developed for brush plating process. A brush applicator will be developed to realize the CNTs reinforced metallic coatings simultaneously. Efforts will be made on brush plating to achieve the desired CNTs alignment and straightness, etc. A through characterization study will be conducted, in terms of coating's hardness, friction and wear, tensile strength, and microstructure. The objectives of this work are: 1) Develop a novel cost effective brush plating method of CNTs reinforced metallic coating fabrication for surface engineering applications; 2) Provide a fundamental understating of how brush plating electrolytes and plating parameters can be used to control the CNTs reinforced metallic composite coating's quality; 3) Understanding CNTs' alignment and waviness stretching mechanism with mechanical work and electrical field during brush plating; 4) Performing various characterization study of the CNT reinforced coatings made by brush plating, including hardness, tensile strength, friction and wear, and microstructure analysis. Intellectual Merit: The proposed research will be the first of such effort to develop an in situ fabrication method of CNTs reinforced metallic composite coatings with brush plating co-deposition method. The novel brush plating co-deposition is expected to overcome underachievement identified in CNTs reinforced polymer composites where interfacial bonding and CNT alignment as well as CNTs' waviness are issues responsible for the underachievement in reinforcement. The success of this work will result in super robust CNTs reinforced metallic nanocomposite coatings for surface engineering applications to meet friction and wear requirements. Theoretical breakthrough is expected on the reinforcement mechanism of carbon nanotubes reinforced metallic composites. Broader Impacts: The proposed research has vast potential applications in surface engineering and broad impacts on science and engineering and huge benefits to society as a whole. The composite coatings will also find broad applications in the thermal management of power electronics because it can be used as ultra high thermal conductors or heat exchangers/spreaders. The composite coatings can be widely used to develop excellent electrical conductors. The brush plating fabricated CNTs reinforced metallic coatings can be used to fabricate MEMS/NEMS devices or components, as brush plated composite filed in predefined micro/nano molds can be released later by removing the molds and separated from the substrate. Graduate students and undergraduate students will involve in the proposed research. The research results will be introduced timely on the web page of PI's Laboratory, Efforts will be made to publish as mush as possible the research results in various professional journals and conferences.
