Product Code: ICAL08_N302

Nanostructural Features in Nanoporous Copper Coatings Fabricated by Laser Deposition
Authors:
Minlin Zhong, Tsinghua University; Beijing Peoples Republic of China
Yide Kan, Tsinghua University; Beijing Peoples Republic of China
Mingxing Ma, Tsinghua University; Beijing Peoples Republic of China
Wenjin Liu, Tsinghua University; Beijing Peoples Republic of China
Ruiquan Kang, Tsinghua University; Beijing Peoples Republic of China
Weiming Zhang, Tsinghua University; Beijing Peoples Republic of China
Hongjun Zhang, Tsinghua University; Beijing Peoples Republic of China
Presented at ICALEO 2008

Nanoporous metals are now attracting more and more attention for their novel physical, chemical and mechanical properties. It is of great scientific and engineering significance to deposit nano-structure on macro-component surface to locally achieve nano-properties for potential applications. Laser deposition offers a promising approach to deposit a designed structure with designed composition on any location of a component. Nanoporous copper coatings with porosities ranging from 30nm to 70nm were fabricated in this work by laser deposition on macro-component surface and following dealloying process. The fabrication process consisted of three steps: 1) laser deposition of a MnxCu1-x powder mixture on steel substrates to obtain layers with exact composition; 2) high speed laser remelting of alloy layers to obtain refined microstructure and more homogeneous composition; 3) electrochemical dealloying of remelted layers to remove the Mn element in the Cu-Mn solid solution to obtain nanoporous structure. This paper focuses on the influence of laser processing and dealloying parameters on the nanostructural features. The results indicate that the dealloying potential takes important part in microstructure evolution of the nanoporous copper coatings. It has a great impact on both the size and the morphology of the nanoporous structure. Microstructural investigations confirm that there is a critical dealloying potential for nanoporous structure formation.