The multiple effects of TiCp addition on the solidification process of cast aluminum alloy

Abstract

The TiCp can act as heterogeneous nucleation site and greatly refine the grain size of aluminum alloy has been widely accepted (stage I). However, its (TiCp) subsequent impact on thermal and solute atoms diffusion for it acting as heterogeneous nucleation site were rarely explored (stage II). In this research, besides the effect on grain refinement, its obvious impacts on cooling rate R and the gradient of solute concentration Gc/temperature GT at the front of solid-liquid interface were also explored in detail. In addition, the exploration results depict that the variation in the parameters of R,GT and Gc caused by TiCp addition can lead to significant changes in the microstructure of the alloy. Besides, unlike the grain refinement caused by its (TiCp) effect on nucleation, some of the changes caused by its (TiCp) effect on the parameters of R,GT and Gc can even make some negative effects on the alloy in some case. Thus, the exploration results in this research can provide a more comprehensive understanding about the TiCp addition in cast aluminum alloy.

Keywords

• TiCp
• Heterogeneous nucleation
• Impacts on solidification parameters and organization/mechanical properties