Rotational rheometry of liquid metal systems: Measurement geometry selection and flow curve analysis

Thermal, Viscoelastic and Surface Properties of Oxidized Field’s Metal for Additive Microfabrication

“…The literature mentions a variety of rheological methods and types of rheometer [ 34 ] used to analyse the viscoelastic properties of liquid metals [ 24 , 35 ]. In this is work, a rotational rheology was used, following the same line of study as Dickey et al [ 15 , 17 ] and Xu et al [ 21 , 22 ], using a TA Instruments “AR-G2” rotational rheometer with a parallel-plate geometry of 25 mm diameter (both upper and lower plates were made of anodized aluminium).…”

Rheology of liquid metals and alloys

“…1 with the double cocentric cylinder (DCC) containment geometry [17] enclosed in a high temperature environment controlled furnace was used to evaluate the flow behavior of three pure metal liquids; Zn (99.99% purity), Sn (99.8% purity) and Cd (99.9% purity); two binary metallic alloys (Bi-42 wt%Sn (commercial alloy purity) and Zn-7 wt%Al (99.999% pure Al was added to 99.99% pure Zn)) and one ternary metallic alloy (Sn-3 wt%Ag-0.5 wt%Cu (commercial alloy purity)), which is a popular lead free soldering alloy. Ultra high purity Argon gas was continuously purged into the furnace chamber at a flow rate of about 10 L min À1 to minimize oxidation of the liquid and the temperature within the furnace was maintained at an accuracy of ±0.5 K. The measuring geometry and rheometer has been elaborately described in Malik et al [17] and were critically calibrated with standard liquids such as S2000 [18], S60 [18] and silicone [19] and verified with de-ionized water. Several rotational rheometry experiments were carried out for each metal system as shown in Table 1.…”

“…Hence, these results, though present qualitative evidence that liquid metals may be non-Newtonian and shear thinning in flow behavior, one could not derive quantitative flow behavior from these results. A unique value of shear rate would have to be maintained in the entire sheared liquid to ascertain the validity of the Newtonian flow behavior in liquids and this could only be possible with few measuring geometries such as the cone and plate and double concentric cylinder (DCC) [17]. In the previous article [17] we have explained the difficulties in the measurement of the liquid metal viscosity and the geometry which is more suitable to use in this measurements.…”

“…A unique value of shear rate would have to be maintained in the entire sheared liquid to ascertain the validity of the Newtonian flow behavior in liquids and this could only be possible with few measuring geometries such as the cone and plate and double concentric cylinder (DCC) [17]. In the previous article [17] we have explained the difficulties in the measurement of the liquid metal viscosity and the geometry which is more suitable to use in this measurements. Further, in Malik et al [17], it was shown that the liquid metals may exhibit a non-Newtonian and shear thinning flow behavior.…”

“…In the previous article [17] we have explained the difficulties in the measurement of the liquid metal viscosity and the geometry which is more suitable to use in this measurements. Further, in Malik et al [17], it was shown that the liquid metals may exhibit a non-Newtonian and shear thinning flow behavior. The flow behavior and viscosity of the various liquid metals and alloys have been quantified for a wide range of shear rate regime and a physical expression for the flow behavior of the liquid metals has been hypothesized in this publication.…”