摘要
The adhesion and wetting of non-reactive liquid metals with solid ionocovalent oxides are studied on the basis of the experimental work of adhesion W data obtained with the sessile drop method.An analysis of the experimental W values of different liquid metals on various solid oxides is first performed to evidence the de- pendence of the work of adhesion of a metal/oxide system on the electron density of the metal and on the thermodynamic stability of the oxide.An electronic model is then proposed to describe the microscopic mech- anism of metal-oxide interactions.Based on the model,the contact angle and the work of adhesion of different liquid metals on various solid oxides can be interpreted and estimated,and their correlations to the various physical quantities of the oxides can be easily deduced.The basic consideration of the model is that the adhe- sion between a metal and an oxide is assured by the electron transfer from the metal into the oxide valence band which is not completely filled of electrons at high temperatures,and is enhanced when this electron trans- fer at the metal/oxide interface is intensified.The influence of interface defects on the wetting and adhesion is suggested and discussed.
The adhesion and wetting of non-reactive liquid metals with solid ionocovalent oxides are studied on the basis of the experimental work of adhesion W data obtained with the sessile drop method.An analysis of the experimental W values of different liquid metals on various solid oxides is first performed to evidence the de- pendence of the work of adhesion of a metal/oxide system on the electron density of the metal and on the thermodynamic stability of the oxide.An electronic model is then proposed to describe the microscopic mech- anism of metal-oxide interactions.Based on the model,the contact angle and the work of adhesion of different liquid metals on various solid oxides can be interpreted and estimated,and their correlations to the various physical quantities of the oxides can be easily deduced.The basic consideration of the model is that the adhe- sion between a metal and an oxide is assured by the electron transfer from the metal into the oxide valence band which is not completely filled of electrons at high temperatures,and is enhanced when this electron trans- fer at the metal/oxide interface is intensified.The influence of interface defects on the wetting and adhesion is suggested and discussed.
