Molten Aluminium Filtration by Ceramic Foam Filter

Molten Aluminium Filtration

Molten aluminium filtration is important for metal smelter. The ceramic foam filter plate is widely used all over the world for its convenience, good filtering effect, and low price. The ceramic filter foam can effectively remove the fineness of aluminum water to reach the inclusion of micron-scale, make aluminum water into stable laminar flow, and is beneficial to punching type. It has unique mullite corundum structure, good mechanical strength and chemical stability, and excellent aluminum water washability.

Molten Aluminium Filtration Mechanism

Cake mechanism: ceramic foam filter composite structure can effectively mechanical slag, when the metal liquid through the structure of the foam ceramic filter is complex, through the mechanical separation of the filter medium, filtering and precipitating the surface of the filter larger than the hole will filter the liquid metal into the end, and become a filter of a group. The inclusions accumulated in the surface area of the filter increase and gradually form a layer of filter cake, which further refines the liquid metal flow. Adding the filter medium surface can filter out more small packages. At the same time, the media also filter effect, in the ceramic body, the number of holes, there is a small gap, or the presence of dead, in different fields, these changes are the possible location of the intercepted inclusions, and there is a “cake” effect in the filter.

Surface effect: when the structure of liquid metal flowing through ceramic body is complex and divided into many streams, the contact area and contact probability of liquid metal inclusion and filter medium are increased, because the filter surface is extremely small convex, and concave, the concave block size is about 1 ~ 10 meters, and the inclusion and electrostatic adsorption and adhesion are intercepted.

Rectification effect: flowing liquid metal foam ceramic filter is divided into many small units of flow and smaller diameter, and the Reynolds number (Re = VD / R) becomes smaller, making the liquid flow tend to laminar flow. When the molten metal is in laminar flow, because the density of liquid metal is much larger than the density of inclusions, so that sufficient time is required to remove floatation, the foam ceramic filter plate can assist the slag. The flow resistance of the filter placed in the gating system increases, and the liquid metal flow forms sufficient movement in the pouring process to reduce the flow rate, which is conducive to the inclusion floating and retaining on the top surface of the runner.

Ceramic Foam Filter Filtration Effect

The use of alumina ceramic foam filter to purify liquid aluminum plate, strip foil, and its products (such as tank car blank, and exquisite decorative materials, PS plate) has brought great benefits. Manufacturers have the following obvious advantages for aluminum alloy profiles:

Increase extrusion yield: when the filter plate is used to purify 15% alloy extrusion billet, we use a specific mold tracking, and find that the extrusion speed is increased by 20%, and the production efficiency is improved by nearly 6063.

The service life of the mould is prolonged and the times of repairing die are reduced.

Reduce extrusion pressure: when the filter plate is used to purify aluminum liquid, the pressure of 6063 is 3% greater than that of non filtration.

The surface quality of aluminum profile is significantly improved.