Casting method of aluminum alloy sacrificial anode

Abstract

The invention belongs to the technical field of corrosion and prevention, and in particular relates to a casting method of an aluminum alloy sacrificial anode. The casting method comprises the following steps: adding basic electrolytic molten aluminum to a resistance furnace; then adding a zinc ingot to obtain molten aluminum alloy; performing jet refining on the molten aluminum alloy by adopting an argon located refining agent; charging argon to refined aluminum alloy melt to degas; drossing oxidizing scum on the surface of the aluminum alloy melt through a drossing tool; adding a low melting point metallic element to drossed aluminum alloy melt; electromagnetically agitating the melt after pressing the low melting point metal; carrying out ceramic filtering; pouring and casting the aluminum alloy melt to a preheated iron anode mould at an even casting speed under the temperature of 700 to 740 DEG C until the mould is full of the aluminum alloy melt; and moving the aluminum alloy melt out of the mould after cooling, solidifying and molding, so as to obtain the aluminum alloy sacrificial anode. The casting method has the characteristics of being short in smelting time, small in loss of iron scale, high in degassing and purifying performances, and low in smelting cost.

Description

technical field [0001] The invention belongs to the technical field of corrosion and protection, and in particular relates to a melting and casting method of an aluminum alloy sacrificial anode. Background technique [0002] At present, the smelting process of aluminum alloy sacrificial anodes at home and abroad is based on primary aluminum ingots with a purity of 99.85% and zinc ingots with a purity of 99.99% as raw materials. Stirring - standing - slag removal - alloying - standing - casting and other processes, the aluminum alloy sacrificial anode is prepared. Furnaces are usually heated by electricity or gas. Since the metal ingot is heated from room temperature to 780°C, the smelting time is long, the energy consumption is high, and the oxidation and burning loss of the metal is serious. Generally, the oxidation burning loss rate is as high as 10%. Due to the lack of refining process in the smelting of sacrificial anode, there are a large number of bubbles and metal o...

AI Technical Summary

Problems solved by technology

Since the metal ingot is heated from room temperature to 780°C, the smelting time is long, the energy consumption is high, and the oxidation and burning loss of the metal is serious, and the general oxidation burning loss rate is as high as 10%.

Due to the lack of refining process in the smelting of the sacrificial anode, there are a large number of bubbles and metal oxide inclusions in the alloy, which lead to positive shift of aluminum alloy sacrificial anode potential, uneven surface dissolution, and reduced current efficiency.

In the production process of aluminum alloy sacrificial anodes, due to the gas and impurities carried by the charge itself, as well as the oxidation and burning of aluminum ingots and zinc ingots during the process of heating, smelting, and transfer, etc., and the gas is absorbed, the aluminum alloy liquid will be damaged. Avoid containing a large amount of oxide inclusions and gases, which will make the fluidity of the alloy liquid worse. After pouring, the sacrificial anode will produce a large number of oxide inclusions, pores and other casting defects, which will affect its solubility, electrochemical performance and appearance quality. Before pouring, it is refined and purified to remove these oxidized inclusions and gases and improve the quality of aluminum alloy liquid

[0003] At present, the refining of alloy melts generally includes solid refining, gas refining, and injection refining of solid and gas mixing, and gas refining is easier to remove gas substances, but the ability to remove oxide inclusions is poor; solid refining can remove oxide inclusions in the melt, but the degassing effect is general

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