Aluminum Alloy Melting Steps

The steps of aluminum alloy melting are as follows:
① Loading. In the preheated mandarin A, pre-alloyed alloy ingots, high-quality recycled materials are added, medium fol alloys are added, and finally alloying elements are added.
②Temperature control. Strictly control the temperature of aluminum alloy smelting. Only suitable temperature can obtain high-quality alloy liquid and avoid overheating. If the temperature is too high, it will increase the oxidative burning of various elements in the alloy, causing changes in the chemical composition of the alloy. If the temperature is too low, the chemical composition of the alloy will be uneven, the oxidized inclusions and gases in the alloy will not be easily discharged, and the physical and chemical properties of the alloy will be reduced, which will affect the casting performance.
③Time control. Strictly control the smelting time, the operation should be rapid, reduce the alloy gettering and oxidation inclusions, increase the burning loss of alloy elements, and affect the alloy chemical composition.
④ Refining operation. The main purpose of aluminum alloy refining is to remove gas and non-metallic inclusions in the melt, and uniform alloy composition. Refining is an extremely important process in smelting. The refining agent should be selected correctly, 0.5% -0.7% of the quality of the alloy should be added in a controlled manner, and the refining temperature should be well controlled. The refining temperature is generally controlled at 700-7200C. During the refining process, use a bell jar to press the refining agent into the melt in batches about 2/3 of the bottom of the melt, and press into the bottom rhyme of Orange A, evenly and slowly rotate clockwise, the speed should be slow, the movement should be smooth, avoid The metal liquid is stirred a lot to prevent increasing the hydrogen content and being involved in inclusions.
⑤ Metamorphism treatment. The purpose of Ming alloy modification is to refine grains and improve casting performance. Modifier should be preheated first, the control points are: ① Modification temperature, generally not more than 7400C; ② Modification time, generally 10min; ③ Addition amount of modifier, the amount of double-color modifier used is generally 1.0% of the quality of alloy liquid- 1.2%; ④ The operation method should be in place. After the alloy refining, the casting should be completed as soon as possible. The sand casting should generally be controlled within 40 minutes, and the metal casting should be controlled within 2 hours. Otherwise, the refining and modification should be carried out again. The refining agent added when refining is about 0.2% of the alloy quality. (Precautions. In order to prevent aluminum alloy splashing, the smelting site should be kept dry; the operator should wear radiation protection glasses, work caps, gloves, and work clothes.)