Effect of the different technological processes during and after casting of hypouetectic aluminium alloys on the eutectic Si particles morphology

Abstract

The purpose of this article is to examine the effect of different technological processes during and after casting of hypoeutectic Al-Si cast alloys on the eutectic Si particles morphology. The changes of Si particles morphology were studied on samples in as-cast states (untreated state). The used technological processes for affecting the Si morphology were: modification with Sb, T4 heat treatment and age-hardening. The best results were achieved with T4 heat treatment, because it caused the greatest changes in morphology of eutectic Si particles and it was the aim of this experiment. Morphology changes were studied with light and scanning electron microscope. A several types of etching methods, which includes regular black and white etching (Dix-Keller; HF), and deep etching (HCl), for studying of structural parameters morphology were used.