Rheological research of partially-solidified dendritic Sn-14.8wt%Pb alloy by two backward extrusion methods

作者：Zhang, Y. F.; Zhou, C.^*; Zhang, Z. H.; Cao, G. M.; Zhang, J.

来源：Materials Science and Technology, 2016, 32(10): 1004-1015.

DOI：10.1080/02670836.2015.1104083

• Strip casting
• Partially-solidified Sn-14.8wt%Pb
• Rheological behaviour
• Backward extrusion

Two different backward extrusion methods were compared to study the rheological behaviour of partially-solidified Sn-14.8wt%Pb alloy for strip casting. For this work, the partially-solidified alloys were dendritic, as opposed to globular semi-solid slurries which have been studied more intensively. The first method was a constant-velocity experiment operating at constant extrusion-velocity of 3.5 mm s(-1) and four different extrusion ratios. The second method was a varying-velocity experiment with unchanged extrusion ratio and four different extrusion velocities.
Both backward extrusion experiments were carried at different temperatures ranging from 183 to 208 degrees C. The two experiments obtained quite different results, which are discussed accordingly. Moreover, an unreported abnormal shear thinning behaviour was the main characteristic of the rheological behaviour of the partially-solidified alloys. Finally, the applicability of these two different methods of measuring the viscosity of partially-solidified alloys at different solid fractions is compared and discussed.

• 出版日期2016
• 单位北京科技大学