The Influence of Cooling Rate on the Microstructure and Microsegregation in Al–30Sn Binary Alloy

Abstract

Aluminum-tin alloys have wide industrial uses, especially in tribological applications. Their structure is consisted of Al-a dendrites (bearing the mechanical load) surrounded by Sn-rich interdendritic layers that function as a solid lubricant. Despite extensive research on solidification behavior of Al-Sn and Al-Sn-based alloys, microsegregation is not yet fully understood. The aim of this article is to study the effect of cooling rate on the microsegregation of Al-30 wt% Sn. Three cooling rates including 3.5, 12.3, and 95.8 K/s were achieved by using three various molds made of sand, brass, and water-cooled brass with the same respective die hole geometries. The results showed that the microstructure becomes much finer with increasing cooling rate. The minimum concentration of Sn in Al was increased by increasing cooling rate approximately four times of equilibrium concentration. The hardness increased mainly as a result of microstructure refinement.

Effects of the PbBr2:PbI2 Molar Ratio on the Formation of Lead Halide Thin Films, and the Ratio’s Application for High Performance and Wide Bandgap Solar Cells

“…For the ratio x up to x = ~0.3, only the single phase (β phase solid solution) is observed, as shown in Figure 1a, implying that approximately 30% of PbBr 2 is dissolved in the β phase, which is much higher than the solubility limit (~5%). The rapid cooling of molten solid solution has been known to form supersaturated sold solutions with the maximum solid solubility much higher than the equilibrium value [39,[45][46][47]. This can apply to the spinning process.…”

Density Functional Theory Study of Structural Evolution, Relative Stability, and Electronic Properties of SnnAln (n = 2–12) Clusters

“…Tin-aluminum alloys are low-eutectic alloys. [1,2] Because the Sn component in Sn-Al alloys can act as a good lubricant and does not generate pollution, Sn is the preferred material for replacing Pb in combination with Al to prepare bearing alloys. [3] Tin-aluminum alloys are generally divided into low-tin aluminum alloys (5-10 wt% Sn), medium-tin aluminum alloys (10-15 wt% Sn), and high-tin aluminum alloys (15-40 wt% Sn), each suited to different application scenarios.…”

Microstructural Changes and Quality Improvement of Al7Si0.2Mg (356) Alloy by Die Vibration

“…The reduction in the degree of microsegregation of Mg and Si in the alloy cast in vibrating die is because of its high cooling rate during solidification. In general, higher cooling rates during solidification even in stationary die reduce solute microsegregation in Al casting 32.…”