Open AccessFinal report for Grant DE-FG02-97ER45655
Author(s) -
P. Wynblatt
Publication year - 2001
Language(s) - English
Resource type - Reports
DOI - 10.2172/808743
Subject(s) - contact angle , wetting , materials science , crystallography , surface energy , alloy , anisotropy , analytical chemistry (journal) , chemistry , metallurgy , physics , composite material , optics , chromatography
Studies were performed of the Au/SiC interface, as well as the interfaces between SiC and several Au alloys. A contact angle of 133{+-}1{sup o} for pure Au on SiC was obtained after equilibration at 800 C. Au containing 3at%Sn was studied, and wetting was improved as evidenced by a decrease in contact angle from 133{sup o} for pure Au to 117{sup o} for the Au-Sn alloy. Sn segregation was observed at the surface of Au. Measurements were also performed on Au-Ge alloys. It was found that the contact angle is decreased to 115{sup o} and 107{sup o} at Ge concentrations of 1 and 2 at%, respectively. Studies of Au containing a low concentration of Si ({approx}0.5 at%) were conducted and showed a decrease in contact angle from 133{sup o} to 107{sup o}. The equilibrium crystal shape of Au was determined. Results showed that the presence of C at the Au surface has a measurable effect on the anisotropy of surface energy. Finally, the wetting of graphite by Pb(Ni) alloys was investigated. The results showed that contact angles of 100{sup o} and 80{sup o} coexist in the vicinity of the limit of solubility of Ni in Pb ({approx}0.17%Pb), without intermediate contact angles being present