Enhanced heterogeneous nucleation of Al6(Fe,Mn) compound in Al alloys by interfacial segregation of Mn on TiB2 particles surface

Revealing heterogeneous nucleation of primary Si and eutectic Si by AlP in hypereutectic Al-Si alloys.

The heterogeneous nucleation of primary Si and eutectic Si can be attributed to the presence of AlP. Although P, in the form of AlP particles, is usually observed in the centre of primary Si, there is still a lack of detailed investigations on the distribution of P within primary Si and eutectic Si in hypereutectic Al-Si alloys at the atomic scale. Here, we report an atomic-scale experimental i...

Enhanced heterogeneous ice nucleation by special surface geometry

The freezing of water typically proceeds through impurity-mediated heterogeneous nucleation. Although non-planar geometry generically exists on the surfaces of ice nucleation centres, its role in nucleation remains poorly understood. Here we show that an atomically sharp, concave wedge can further promote ice nucleation with special wedge geometries. Our molecular analysis shows that significan...

PRECIPITATION STRENGTHENING BEHAVIOR OF Al-Cu-Mn ALLOYS WITH THE EFFECT OF CASTING SEGREGATION

Al-Cu-Mn is one of typical heat-treatable cast alloys with high strength which has been widely used in aerospace and automobile industries. The complete manufacturing process for AlCu-Mn components includes low pressure die casting, T6 heat treatment and machining. It has been found that the property in former process has been transferred to the sequent step with considerable effect. In this pa...

Surface segregation in binary alloys

Study of Heterogeneous Nucleation of Eutectic Si in High-Purity Al-Si Alloys with Sr Addition

Al-5 wt pct Si master-alloys with controlled Sr and/or P addition/s were produced using super purity Al 99.99 wt pct and Si 99.999 wt pct materials in an arc melter. The master-alloy was melt-spun resulting in the production of thin ribbons. The Al matrix of the ribbons contained entrained Al-Si eutectic droplets that were subsequently investigated. Differential scanning calorimetry, thermodyna...