Fluidity Investigation of Pure Al and Al-Si Alloys

Abstract

Fluidity tests of pure aluminum 1070 and Al-Si alloys with Si contents of up to 25% were conducted using a die cast machine equipped with a spiral die. The effects of the channel gap, die temperature, and injection speed on the fluidity were investigated. When the channel gap was small (0.5 mm), the flow length of the 1070 was minimized, and the fluidity increased monotonically at a gradual rate with increasing Si content. In contrast, larger gaps yielded convex fluidity–Si content curves. Additionally, heating the die had less of an influence on the fluidity of the 1070 than on that of the Al-Si alloy. These results are discussed in the context of the peeling of the solidification layer from the die based on the thicknesses of foils and strips cast by melt spinning and roll casting, respectively. At lower Si contents, heat shrinkage was greater and the latent heat was lower. When the heat shrinkage was greater, the solidification layer began to peel earlier, and the heat transfer between the solidification layer and the die became smaller. As a result, the fluidity of the 1070 was greatest when the channel gap was 0.8 mm.

Die Casting of Lightweight Thin Fin Heat Sink Using Al-25%Si

“…However, the present results demonstrate that Al-25%Si has superior fluidity. Al-25%Si has notably higher latent heat than ADC12 due to its higher Si content [19]. As a result, the flow length of Al-25%Si is excellent and indicates potential for die casting of thin products.…”

“…The aluminum alloy was melted in an oxidizing atmosphere using a gas furnace. The spiral die used to investigate the flow length features a channel width of 7 mm and channel gaps of 0.5 and 1.0 mm, as shown in Figure 1 [19]. The shape and name of each part of the heat sink are shown in Figure 2.…”

“…It is thought that an aluminum alloy with excellent fluidity can flow into thin die gaps, allowing for the casting of thin fins. In a previous study, it was shown that hyper-eutectic Al-25%Si has excellent fluidity compared to hypo-eutectic Al-Si alloys [19]. JIS ADC12 (similar to A383) [20] is a popular aluminum alloy for die casting, and it is typically used to cast heat sinks.…”

Role of silicon on the tribological performance of Al-based automotive alloys and the effect of used motor oil

“…The Si addition makes the alloy of good strength, corrosion resistant, increased fluidity and free from hot shortness. Furthermore, the hard phase of Si contributes to transform the alloy into a highly wear resistant one [4,5]. Combining with other elements, the Si particles upgrade the strength and make the alloys heat treatable.…”

Experimental Investigation and Numerical Simulation of the Fluidity of A356 Aluminum Alloy

“…Fluidity is not a physical property, such as density, but a complicated behavior related to the fluid flow and solidification of the liquid or liquid-solid two-phase of an alloy under specific conditions of a casting practice. Therefore, fluidity can be affected not only by the thermodynamic characteristics of the alloy (alloy chemistry [1][2][3][4][5][6][7][8][9], melt temperature [7,10,11], and viscosity [12,13], etc.) but by various parameters of fluidity tests (measurement method [1,14], mold temperature [15,16], mold coating [17,18], etc.).…”