Thin wall aluminum die casting technology
Thin aluminum die casting technology
Close relationship between die casting wall thickness and the filling time, the thinner the wall, filling the shorter the time.
Can provide a stable fast injection speed, high-performance die-casting machines and high-speed filling conditions do not occur flash high-precision; high rigidity of the mold is a necessary condition of the thin aluminum die-casting.
Summarizes the flow length of the aluminum alloy die casting in different wall thickness, wall thickness of 1.0mm, the following definitions for the thin-walled.
Ultra book wall die casting process points:
A release agent to use high temperature adhesion and good oil and water-based mold release agents, spray time is shorter, and the release agent at high concentrations.
(2) the injection chamber pouring prevent injection indoor temperature of molten aluminum to reduce and filling low, should adopt the ceramic cavity injection chamber or by direct heating of injection room, and good thermal insulation effect of the powder lubricant and The hot pressing radio room also have good results.
(3) Injection filling must have a very high injection speed. More general use of die casting machine and ultra-thin, ultra-thin die-casting die-casting machine, the P-Q2 Figure must have a large injection pressure. In order to ensure a stable high-speed injection, injection room must have adequate lubrication is recommended to use oil-based lubricants. The back pressure of the cavity will prevent the high-speed injection, should take full account of the cavity of the exhaust, vacuum die casting can be used. Injection indoor exhaust if we consider the better;
Solidification prone to shrinkage and crack, thin-walled die-casting during solidification and shrinkage of the casting structure should be possible to make uniform thickness, and to prevent the crack response is to be located at the corner fillet.
Mold pickup mold as soon as possible to the top of the casting, hot shrinkage stress small pickup is best.
Thin-wall die-casting mold points:
Shape castings wall thickness should be uniform, and set the rounded corners and ribs and the taper angle. Cavity surface can be polished bright appropriate blasting to improve mobility and prevent mold cracking;
2 gating system first injection chamber diameter and the location of the ingate, the diameter of the injection chamber is determined by the filling time and filling rate; ingate wide, shorten the distance and smooth filling points. Thin and small size, the structure of the runner as far as possible, to eliminate the volume gas; overflow tank is not too large, otherwise boost slow and easy to cause shrinkage and crack;
The mold temperature is kept high mold temperature, can use oil for heating and electric heating, it is recommended to use electric heating. To ensure that the insulation effect can be set in the insert on the back of the insulation materials;
The four top ultra thin-walled die casting as much as possible with a larger mandrel, can also make use of variable cross-section mandrel to prevent mandrel bending deformation.