Refining agent is a kind of product commonly used in industry, but there are various problems and types in oxide. In this article, we will briefly explain. Types of oxide inclusions in high performance aluminum alloy refiners.

Types of oxide inclusions

In the process of refining agent disposal and transportation, oxide scale, intermetallic compound, furnace debris and other heterogeneous substances are easy to be brought into the molten metal to form non-metallic inclusions, which are mainly oxide inclusions. It can be divided into primary oxide inclusion and secondary oxide inclusion according to the different composition periods in the process of setting and casting.

The primary oxide inclusion of refining agent mainly refers to all oxide inclusions formed before the pouring of aluminum liquid. The primary oxide inclusions can be divided into two categories according to their shapes: one is the large inclusions scattered unevenly in the macro structure, which make the alloy structure discontinuous, reduce the air tightness of the workpiece, become the source of corrosion, obviously reduce the strength and plasticity of the aluminum alloy, and often become the crack source of the parts; the second category of oxide inclusions refers to the small and dispersed inclusions, Even after careful purification, it can not be completely removed. It increases the viscosity of the liquid metal, reduces the feeding ability of the liquid aluminum during solidification, and easily forms the shrinkage porosity of the casting.

The secondary oxide inclusions of refining agent, also known as endogenous inclusions, are mainly formed in the pouring process. Generally speaking, the distribution of endogenous inclusions is relatively average, and the particles are also relatively small. Splashing and turbulent flow in the process of pouring are the main sources of secondary oxide inclusions. In the sand mold, the aluminum liquid interacts with the water in the molding sand, and is synthesized into oxygen and hydrogen through water. Oxygen interacts with aluminum to form oxide inclusions, and hydrogen dissolves in the aluminum liquid.