How to design a die cast

- Jul 10, 2017-

(1), to avoid the core cross; reasonable die casting structure can not only simplify the die-casting structure, reduce manufacturing costs, the manufacture of die-casting, But also improve the quality of castings.


(2) Casting wall thickness requirements (usually wall thickness) is a die-casting process in a special significance of the factors, the wall thickness and the entire process specifications are closely related, such as the filling time calculation, the gate The choice of speed, the calculation of the solidification time, the analysis of the temperature gradient of the mold, the effect of the pressure (final pressure), the length of the mold stay, the height of the casting temperature and the operating efficiency; a, B, casting wall thickness can not be too thin, too thin will cause poor filling of aluminum, forming difficult, so that the aluminum alloy welding is not good, the thickness of the casting is not good, The casting surface is easy to produce cold and other defects, and to the die-casting process difficult; die with the wall thickness increases, the internal pores, shrinkage and other defects increased, so in ensuring the castings have sufficient strength and stiffness under the premise, Should try to reduce the casting wall thickness and maintain the thickness of the cross-section uniform, in order to avoid shrinkage and other defects, the thickness of the casting should be thicker (minus), increase the tendons; for large areas of flat Wall castings, set ribs to reduce the wall thickness of castings; according to the surface area of die castings, aluminum alloy die casting reasonable wall thickness as follows: die casting surface area / mm2 wall thickness S / mm ≤ 251.0 ~ 3.0> 25 ~ 1001.5 ~ 4002.5 to 5.0 & gt; 4003.5 to 6.0.


(3) casting design requirements of the ribs:


The effect of the ribs is to improve the strength and rigidity of the parts, to prevent the reduction of the shrinkage and deformation of the parts, and to prevent the workpiece from deforming from the top of the mold when filling the auxiliary circuit (the flow of metal) , The thickness of the die casting bar should be less than the thickness of the wall, generally take the thickness of the 2/3 ~ 3/4.


(4) casting design of the rounded requirements:


The connection between the wall and the wall on the die, regardless of the right angle, the acute angle or the obtuse angle, the blind hole and the root of the groove, should be designed as rounded corners and only if the corners are expected to be part of the parting surface , The rest of the general must be rounded corners, fillet should not be too large or too small, too small die castings easy to produce cracks, too easy to produce loose shrinkage, die casting fillet generally take: 1/2 wall thickness ≤ R ≤ wall The effect of the fillet is to help the flow of the metal, reduce the vortex or turbulence; to avoid the presence of rounded corners on the existence of stress concentration and lead to cracking; when the parts to be plated or coated, fillet available Uniform plating, to prevent the deposition at the corners; can extend the service life of die-casting mold, not due to the presence of mold cavity angle caused by collapse or cracking.