Electrowetting Of Liquid Metal On Metal Substrate And Liquid/Solid Interfacial Reaction

The wetting of liquid metal on solid and interfacial interaction is commonphysical-chemistry phenomena in the material fabrication and processing. Thisresearch is important for both the basic theory and practical application. The researchof this paper mainly includes the following aspects:Wetting behavior of Hg and Na-K drop on nanoporous anodic aluminum oxidesubstrate (AAO) was studied. Experimental results showed that: wetting of Hg andNa-K drop on anodic aluminum oxide substrate was in Cassie wetting state. Thecontact angle of Hg or Na-K on AAO reduced with the increase of applied voltageuntil the saturation of the electrowetting. The Hg/AAO system immersed in kerosenehad a larger changes of the contact angle and lower contact-angle hysteresis (CAH)compared to the system in air. The Na-K/AAO system immersed in kerosene had avery low contact-angle hysteresis and the change of the contact angle due to theelectrowetting effect is20o.The interfacial interaction in Zn(l)/Zr(s), Al(l)/Zr(s), Zn32.4-Al(l)/Zr(s) andZn67.6-Al(l)/Zr(s) reaction couples was studied. Experimental results showed that:the reaction layers consists of Zn3Zr, Zn39Zr5and Zn22Zr, and the growth of theinterfacial reaction layers satisfied a parabolic relationship in Zn(l)/Zr(s) couples. Inthe Al(l)/Zr(s) couples, the reaction layers consists of ZrAl3and ZrAl2, and theinterfacial reaction layer grows in a parabolic rule. In the Zn32.4-Al(l)/Zr(s) andZn67.6-Al(l)/Zr(s) couples, the phase of the reaction layers is mainly composed ofAl3ZnZr2and Al2ZnZr. The growth of interfacial reaction layers satisfied a linearrelationship in Zn32.4-Al(l)/Zr(s) couples.A special attention was paid to the geometrical effect of interaction layers growthat the corner. In the Zn67.6-Al(l)/Zr(s) couples, the growth of interfacial reactionlayers exhibits a typical cruciform pattern.