Đang chuẩn bị liên kết để tải về tài liệu:
Báo cáo hóa học: "Friction and Shear Strength at the Nanowire–Substrate Interfaces"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Friction and Shear Strength at the Nanowire–Substrate Interfaces | Nanoscale Res Lett 2010 5 291-295 DOI 10.1007 s11671-009-9478-4 NANO EXPRESS Friction and Shear Strength at the Nanowire-Substrate Interfaces Yong Zhu Qingquan Qin Yi Gu Zhong Lin Wang Received 6 September 2009 Accepted 28 October 2009 Published online 28 November 2009 to the authors 2009 Abstract The friction and shear strength of nanowire NW -substrate interfaces critically influences the electri-cal mechanical performance and life time of NW-based nanodevices. Yet very few reports on this subject are available in the literature because of the experimental challenges involved and more specifically no studies have been reported to investigate the configuration of individual NW tip in contact with a substrate. In this letter using a new experimental method we report the friction measurement between a NW tip and a substrate for the first time. The measurement was based on NW buckling in situ inside a scanning electron microscope. The coefficients of friction between silver NW and gold substrate and between ZnO NW and gold substrate were found to be 0.09-0.12 and 0.10-0.15 respectively. The adhesion between a NW and the substrate modified the true contact area which affected the interfacial shear strength. Continuum mechanics calculation found that interfacial shear strengths between silver NW and gold substrate and between ZnO NW and gold substrate were 134-139 MPa and 78.9-95.3 MPa respectively. This method can be applied to measure friction parameters of other NW-substrate systems. Our results on interfacial friction and shear strength could have implication on the Y. Zhu H Q. Qin Department of Mechanical and Aerospace Engineering North Carolina State University Raleigh NC 27695 USA e-mail yong_zhu@ncsu.edu Y. Gu Department of Physics Washington State University Pullman wA 99164 USA Z. L. Wang School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA 30332 USA AFM three-point bending tests used for nanomechanical characterisation. .