With the progress of society and the development of industry, Shandong Aluminum alloy die casting is more and more widely used. In the early stage, we also introduced the operation process of aluminum alloy die casting, and we will encounter some problems in the process. How can you solve them! So today, Jinan Hongjie mould Co., Ltd. will take you to know about it!
I. how to achieve good modeling effect for die-casting aluminum parts?
(1) for the parts with thick local area in die casting aluminum, it is necessary to be very careful to set risers on them so as to prevent the process hot spot from forming again on the basis of the original hot spot. In the parts with thick local area, the effect of using cold iron is often better than that of using only risers.
(2) for the die-casting aluminum parts with more grids and diaphragms, in order to avoid the defect of insufficient pouring, in addition to aligning the inner gate with the grid or diaphragms, the exhaust of the casting itself is also a very important process element.
(3) in sand casting, for the castings with too large size and no suitable sand box, and for the castings with more than one complex cavity, the method of group mold and core mold can achieve better results.
(4) during core molding, the following four aspects should be grasped: the stability of core placement; the accuracy of core positioning; the operability of core molding; the compatibility of core and other process elements. During the formation molding, sand enclosure shall be carried out outside the formation sand block to prevent leakage.
(5) for ring or frame castings with thin wall thickness, when the pouring system is set in the center of the casting, the sprue between the straight sprue and the transverse sprue ring is made into a fold line form to prevent the casting from deformation and crack due to tensile stress during shrinkage.
2. How to prevent the liquid metal from oxidation during the pouring process?
(1) adjust the carbon content and carbon equivalent of molten iron, increase the spheroidizing temperature and strengthen the inoculation treatment, reduce the viscosity and improve the fluidity of molten iron;
(2) on the premise of ensuring spheroidization, reduce the amount of magnesium added to the die casting aluminum to reduce the amount of residual magnesium in nodular cast iron;
(3) smelting nodular cast iron with excellent furnace charge, reducing the sulfur content of the original molten iron, gas and inclusion content;
(4) the ladle with good slag retaining effect shall be used. Before pouring, the molten iron shall stay in the ladle for enough time to make the slag and inclusions fully float;
(5) smelting and pouring magnesium alloy in protective atmosphere to prevent the liquid metal from oxidation;
(6) the pouring position and pouring system of die-casting aluminum parts should be set to ensure that the molten metal can fill the cavity quickly and stably, shorten the filling process, and adopt vacuum suction casting;
(7) adjust the alloy composition to improve its fluidity, properly raise the pouring temperature and pouring speed, prevent the molten metal from oxidization during pouring, improve the composition of molding sand and coating to prevent the chemical reaction between the mold wall and the molten metal, allow the ladle to stand for enough time and strengthen the slag retaining, properly raise the mold temperature during the casting of the metal mold;
(8) easily oxidized alloy steel is poured in reducing or neutral atmosphere;
(9) in the pouring system, a filter screen and a slag collecting bag are arranged;
The above is from Jinan Hongjie Mold Co., Ltd. how to achieve good modeling effect and how to prevent the oxidation of molten metal in the pouring process. I hope it can help you! For more information, please click http://www.hfonsu.icu