Research on causes of hot-tearing of AA3003 aluminum billet during DC casting process

AA3003 aluminum alloy made from raw scrap materials that have the advantage of economical use, but hottearing often occurs in the product billets of the direct chill casting process. This study used ANOVA analysis method for determination of chemical composition of AA3003 aluminum billet products to show influence of chemical composition on hot-tearing ability. The evaluation of the microstructure and chemical composition distribution of the elements by optical and scanning electron microscopes combined with energy dispersive spectroscopy showed the existence of impurities such as Cu, Zn, Fe, Pb exceeding the allowable limit in aluminum billets, especially at grain boundary, which can be the main reason for the hot-tearing of cast aluminum billets.

Finite Element Analysis of Direct Chill Casting using Concept of Element Birth and Death

A direct chill (DC) casting is a continuous casting process widely used in different industries. The aim of the work is to investigate thermal and mechanical stress formed during the direct chill casting process by a numerical method. A commercial software ANSYS mechanical APDL is used for the simulation. A moving mesh technique is employed for the development of ingot during the solidification process. An element birth and death concept is used to find out the deformation in ingot. The verification of the results is done with the results found in literature and found a good agreement. The developed model has admirable ability to predict the thermal and mechanical stress formed in direct chill casting process.

Influence of Fe and Si Addition on the Properties and Structure Conductivity Aluminium

The effect of iron and silicon addition on the structure and properties of aluminium wire rod obtained in the laboratory horizontal direct chill casting process has been analysed. In addition, the impact of laboratory wire drawing process has been examined. The addition of iron and velocity of casting increase the strength of aluminium wire rod in as-cast condition while the electrical conductivity drop acceptable. Moreover, the laboratory wire drawing process causes work-hardening wires and increase drawing tension as a result of fragmentation of structure and growth of grain boundaries. It has been shown that iron is beneficial for mechanical and technological properties of aluminium.

Microstructural and Mechanical Characteristics of Cladding Billets with Different Clad Ratios

AA4045/AA3003 cladding billets with different clad ratios were fabricated by direct chill casting process. The macrostructures, microstructures, compositions distribution and the mechanical properties near the bonding interface were investigated in detail. The results show that the cladding billet with few defects could be obtained by semi-continuous casting process. The metallurgical bonding was formed due to the diffusions of elements. The decreasing of clad ratio changed the microstructure at the interface and reduced the thickness of diffusion layer. The hardness around the interface is higher than that of AA3003 side but lower than that of the other side, indicating that the interface yield strength is also higher than that of AA3003. After extrusion process, the characteristics of the interface remain that of as-cast cladding billet.