Sessile drop technique

About: Sessile drop technique is a research topic. Over the lifetime, 2827 publications have been published within this topic receiving 68943 citations.

Density and Surface Tension of Liquid Fe-Mn Alloys

Abstract: The density and surface tension of liquid Fe-Mn alloys were determined by using the sessile drop method at 1823 K (1550 °C). The density of liquid Fe-Mn alloys decreased with increasing Mn content. When the molar volume was plotted with respect to the mole fraction of Mn, a linear relationship was obtained. Consequently, it was found that there is no excess volume in liquid Fe-Mn alloy. The surface tension of liquid Fe-Mn alloys was found to decrease with increasing Mn content. The current experimental data were higher than the reported results but close to the calculated results using Butler’s equation.

Some Thermophysical Properties of Liquid Cr‐Mn‐Ni‐Steels

Abstract: In the last years new Cr-Mn-Ni-TRIP/TWIP steels have been developed at the Institute of Iron and Steel Technology, Freiberg University of Mining and Technology. Within the Collaborative Research Center SFB 799, the ZrO2-ceramic-TRIP-steel composite materials are produced using the infiltration of open foam ceramics with liquid steel and using powder metallurgy with small additions of ceramic powder before sintering. The thermophysical properties of liquid steel play an important role in both production routes. They affect the infiltration efficiency in one process and the produced powder size in the other, and therefore finally determine the composite properties. In this work some of these properties were estimated, as they are not available in literature. The investigated steels contain approximately 16% chrome, 7% manganese and 3% to 9% nickel. The surface tension was estimated using two methods: the drop weight method and the maximum bubble pressure method. In the drop weight method similar conditions at the gas/metal interface exist as during the atomization or the infiltration process, where liquid metal is exposed to high volume of inert gas. In all these cases the evaporation of manganese affects the surface tension. For comparison of results and for estimation of the liquid steel density the maximum bubble pressure method was used where the evaporation of manganese is limited. The wettability on partially MgO-stabilized ZrO2 ceramic substrates and its change with contact time was determined using the sessile drop method.

The effect of large oxygen additions on the wettability and work of adhesion of copper-oxygen alloys on polycrystalline alumina

Abstract: The apparent contact angle, the solid-liquid interfacial energy, and the work of adhesion were determined for liquid copper and copper-oxygen alloys on polycrystalline alumina using a sessile drop technique. The oxygen contents were varied from 1 to 11 wt.% and the temperature was varied from 1135 to 1300°C. Most studies of this system have centered on considerably lower oxygen contents. In this study, three regions of wetting behavior were observed. These regions correlated with three liquid regions on the copper-oxygen binary phase diagram. For 0.001–3 wt.%, the contact angle decreased and the work of adhesion increased significantly as the oxygen content increased. Within the immiscible liquid composition range (3–7.5 wt.%), the contact angle and work of adhesion were approximately constant. At higher oxygen contents (8–10.5 wt.%), only slight changes in the contact angle and work of adhesion were observed. At 10.5 wt.%, the contact angle achieved a minimum of 12 ± 4° and the work of adhesion reached a maximum value of 1340 ± 60 mJ m −2 .

Sessile drop deformations under an impinging jet

Abstract: The problem of steady axisymmetric deformations of a liquid sessile drop on a flat solid surface under an impinging gas jet is of interest for understanding the fundamental behavior of free surface flows as well as for establishing the theoretical basis in process design for the Aerosol \({{\rm Jet}^{\circledR}}\) direct-write technology. It is studied here numerically using a Galerkin finite-element method, by computing solutions of Navier–Stokes equations. For effective material deposition in Aerosol \({{\rm Jet}^{\circledR}}\) printing, the desired value of Reynolds number for the laminar gas jet is found to be greater than ~500. The sessile drop can be severely deformed by an impinging gas jet when the capillary number is approaching a critical value beyond which no steady axisymmetric free surface deformation can exist. Solution branches in a parameter space show turning points at the critical values of capillary number, which typically indicate the onset of free surface shape instability. By tracking solution branches around turning points with an arc-length continuation algorithm, critical values of capillary number can be accurately determined. Near turning points, all the free surface profiles in various parameter settings take a common shape with a dimple at the center and bulge near the contact line. An empirical formula for the critical capillary number for sessile drops with \({45^{\circ}}\) contact angle is derived for typical ranges of jet Reynolds number and relative drop sizes especially pertinent to Aerosol \({{\rm Jet}^{\circledR}}\) printing.