Effect Of Electric Current On The Wetting And Interfacial Reaction Between Liquid And Solid Metal

The wetting of liquid on solid and interfacial interaction between liquid and solid metal usually occur in the material fabrication and processing, which decide the possibility of material fabrication and properties. The effect of applied current on the wetting of liquid/solid metal and interfacial reaction was chosen as the research object in this thesis. The research work mainly include the following aspects:1. The effect of electric current on the interfacial reaction of SnBi eutectic alloy melt/Cu reaction couple at various temperatures was studied. The experimental results showed that the interfacial reaction products of SnBi eutectic alloy melt/Cu reaction couple without applied electric current consisted of the scallop-type Cu6Sn5 layer and thin Cu3Sn layer. Applied electric current would enhance the growth of interfacial reaction layer of SnBi eutectic alloy melt/Cu reaction couple. The thickness of the anodic interfacial reaction layer was thicker than that of the cathode interfacial reaction layer in SnBi eutectic alloy melt/Cu/SnBi eutectic alloy melt reaction couple with applied electric current apparently.2. The effect of current on the interfacial reaction of SnZn eutectic melt /Cu/SnZn eutectic melt reaction couple was investigated The experimental results showed that a singleγ-Cu5Zn8 reaction layer was formed at the interface of SnZn eutectic melt /Cu reaction couples with (or without) applied current. The thickness of the anodic interfacial reaction layer was thicker than that of the cathode interfacial reaction layer in SnZn eutectic alloy melt/Cu/SnZn eutectic alloy melt reaction couple with applied electric current apparently.3. The effect of DC current on the wetting behavior of pure Bi melt on Cu substrate at 370℃by using the sessile drop method was investigated in the third part. Without the applied current, melt bi didn't wet on the Cu substrate,the spreading time was about 30 minute to achieve steady-state contact angle (about 102o).As the current increased, the dissolution of Cu in the melted Bi was dramatically accelerated, The equilibrium contact angle decreased significantly simultaneously. Applied current significantly contributed Cu dissolved in the melt Bi, which would changed the wetting-phase line configuration. This improvement of the wettability caused by current also have sth to do with the additional wetting driving force provided by the electromagnetic pressure gradient.4. The effect of a direct electric current on the wetting behavior of eutectic SnBi melt on Cu substrate at 220℃was investigated in the fourth part. It was found that the application of current enhanced the growth rate and lateral growth of interfacial reaction layer between eutectic SnBi melt and Cu substrate.Furthermore, with the increase of the current, the spread of eutectic SnBi melt on Cu was accelerated significantly and the steady-state contact angle was decreased markedly. The reason for these is also discussed in this part.These research results will provide a new way on the regulation of the wetting of liquid on solid and interfacial interaction between liquid and solid metal.