[Chinese aluminum industry network] applies to gravity casting and die casting aluminum-silicon alloy (including Al-Si-Mg, Al-Si-Cu, etc.) guidance document: "aluminum alloy smelting specification." (1) General rules 1 The castings produced in accordance with this document shall have chemical composition and mechanical properties that comply with GB/T9438-1999 Aluminum Alloy Castings, JISH5202-1999 Aluminum Alloy Castings, and ASTM B108-03a Aluminum Alloy Metal Castings. , GB/T15115-1994 "die-cast aluminum alloy", JISH5302-2006 "aluminum alloy die casting", ASTMB85-03 "aluminum alloy die casting", EN1706-1998 "cast aluminum alloy" and other standards. 2 The smelting of aluminum alloys referred to in this document is carried out in resistance furnaces, induction furnaces and gas (natural gas) furnaces. Take graphite crucible or cast iron crucible generally. Cast iron must be liquid aluminized. (2) Ingredients and charge materials 1) Ingredient calculation 1 Magnesium batch calculation amount: When using chlorine salt refining, the upper limit should be taken. When refining with non-pollutant refining agent, it can be appropriately reduced; or the amount of magnesium added can also be adjusted according to actual conditions. 2 When aluminum alloy die-casting, in order to reduce the die-casting phenomenon during die-casting, it is allowed to properly increase the iron content, but it shall not exceed the provisions of the relevant standards. 2) Metal materials and recycled materials 1 New metal materials Aluminum ingots: GB/T1196-2002 "Ingots for Remelting" Aluminum-silicon alloy ingots: GB/T 8734-2000 "cast aluminum-silicon alloy ingots" Magnesium Ingot: GB3499-1983 Magnesium Ingot Aluminum-copper master alloy: YS/T282-2000 "Aluminum intermediate alloy ingot" Aluminium-manganese master alloy: YS/T282-2000 "aluminum intermediate alloy ingot" Various grades of prefabricated alloy ingots: GB/T 8733-2000 "cast aluminum alloy ingot", JISH2117-1984 "recycled aluminum alloy ingot for casting", ASTMB197-03 "cast aluminum alloy ingot", and JISH2118-2000 "die cast aluminum alloy ingot" , EN1676-1996 "casting aluminum alloy ingots" and so on. The 2 return charge consists of scrap castings with well-defined chemical composition, top feeders and leftovers at the bottom of the crucible, as well as crushing heavy melting ingots such as overflow tanks and flashes. The amount of recycled material is generally not more than 80%, in which the crushing and remelting material does not exceed 30%; for unimportant castings, the recycled material can be used in all; for special requirements (airtightness, etc.), the amount of returned material of the casting shall not exceed 50%. . 3) Debris removal In order to improve the product quality, dirt, oil, and inserts on the scrap casting must be removed from the charge surface and should be removed before smelting (a smelting furnace can be used to remove the inserts). 4) The preheating of the charge is generally kept at 350-450°C for 2-4 hours. Zn, Mg, and RE are maintained at 200 to 250°C for 2 to 4 hours. Under the circumstance that the enamel coating is complete and fully preheated, the charge materials except flammable materials such as Zn, Mg, Sr, Cd, and RE are allowed to be preheated with the furnace. (3) Preparation of refining agent 1 The refining of aluminum alloys generally uses refining agents such as hexachloroethane, DSG aluminum alloy degassing degassing agent, and aluminum refining agent ZS-AJ01C. 2 Hexachloroethane is placed in the furnace for preheating before use. 3DSG aluminum alloy refining agent such as slag degassing agent, aluminum refining agent ZS-AJ01C, etc., should be stored to prevent moisture absorption, and should be placed near the furnace before use. (4) Preparation of crucibles and smelting tools