The key to the magnesium alloy melting process is flame retardant protection, followed by refining treatment to remove metal and non-metal impurities, slag inclusions, and harmful gases from the magnesium alloy melt.
(1) Preparation work
Prepare all tools, inspect the crucible, clean the slag and other debris in the furnace, inspect the resistance wire, ensure that the temperature measuring thermocouple is in the normal position, and ensure that the electrical control and automatic temperature control are normal, sensitive and accurate;
(2) Preheating of crucibles and furnace materials
Preheating the furnace material to remove moisture, prevent safety accidents such as explosions, and reduce the increase in gas content brought into the alloy liquid by moisture in the furnace material.
(3) Material melting
Add preheated furnace material to the preheated crucible and heat it up to melt.
(4) Alloying and refining
After the temperature rises above the melting temperature, add the intermediate alloy to the magnesium ingot and stir thoroughly
Mix evenly, then heat up to the appropriate temperature, and sprinkle refining agent into the melt for refining. The key to this process is to control the amount of alloy added and the refining temperature, which are determined by different types of alloys.
(5) Let it stand still
The purpose of the settling process is to precipitate impurities with higher density in the magnesium alloy liquid, so it is necessary to control the temperature and time of the settling.
(6) Casting
After settling, take samples for analysis. Once the composition is qualified, control the casting temperature for casting.
Flame retardant protection should be carried out throughout the entire melting process, and the protection methods include: covering the melt with salt solvents and continuously adding them; Process the melt in an atmosphere of mixed protective gas to form a thin protective layer on it. The specific method used depends on the production process.