The parameters of zinc alloy die-casting are specific p […]
The parameters of zinc alloy die-casting are specific pressure and filling speed, both of which are the most important process parameters in the die-casting process. Other process parameters include filling time and mold temperature.
Die casting is a metal casting process, which is characterized by using a mold cavity to apply high pressure to the molten metal. The mold is usually made of a stronger alloy, and the process is somewhat similar to injection molding.
Most die castings are iron-free, such as zinc, copper, aluminum, magnesium, lead, tin and lead-tin alloys and their alloys.
Depending on the type of die casting, a cold chamber die casting machine or a hot chamber die casting machine is required.
Zinc alloy is an alloy composed of zinc as the base to participate in other elements. Commonly added alloying elements are low-temperature zinc alloys such as aluminum, copper, magnesium, cadmium, lead, and titanium.
Zinc alloy has a low melting point, good fluidity, easy fusion welding, brazing and plastic processing, corrosion resistance in the atmosphere, and the residual waste material is easy to recover and remelt; but the creep strength is low, and it is easy to cause natural aging to cause dimensional changes.
Prepared by melting method, die-casting or pressure processing into materials. According to the manufacturing process, it can be divided into cast zinc alloy and deformed zinc alloy.
Because zinc alloy die-casting has good die-casting and mechanical functions, it has always adhered to an important position in hot-chamber die-casting.
The advantages of zinc alloys are low melting point, slow melting and heat preservation, and less heat in the pressure chamber and die casting mold wall. How to reduce the shortcomings, and manufacture zinc alloy die castings that meet the requirements, mainly have the following elements:
Choose the right die casting machine
The die-casting machine is the key equipment for the production of die-casting, and the quality of its functions objectively determines the quality of the die-casting parts. The correct choice of die casting machine is essential to ensure product quality, improve production efficiency, and reduce production cost. The function of die casting machine depends on two aspects.
Satisfactory clamping force: prevent the highest peak of metal melt pressure, showing flash and flying material.
Satisfactory injection ability: ensure that the die does not overheat or overflow during die casting, and ensure that the machine has sufficient molten metal to deliver and fill the cavity at the required speed in a short time.
Die casting mold runner planning
Because the zinc alloy must fill the cavity in a short time, the planning and manufacturing of the die casting mold and its runner system is much higher than that of the plastic mold. The flow channel system is to guide the metal solution to fill the cavity with a certain method. It plays an important role in the flow direction of the metal liquid, pressure transmission, filling time, exhaust conditions, and mold temperature distribution.
It is also an important factor in determining the quality of die castings. The planning principle of the runner system of the die-casting mold should be aggregated from the gooseneck to the gate to prevent sharp corners. The appearance of the process diameter should be lubricated in order to reduce resistance and maintain the flow speed of the liquid zinc alloy.