A mold or mould are the common terms used to describe the tool used in the manufacturing process, both die casting and injection molding use the molds to create parts. Then, how do they work and what’s the difference between die casting mold and plastic injection mold?

What is Die Casting Mold?

Die casting mold, also known as the die or tool used in the die casting process, contains the mold cavity which is created using two hardened tool steel dies and used to form the contours and dimensions of the casting. A die casting mold is made of two parts and consists of fixed and movable mold shelves. The fixed half die is installed on the fixed plate of the die casting machine; The ejector half die is fixed on the movable fixed plate, including the casting ejector.

What is Plastic Injection Mold?

Plastic injection mold refers to the tooling used to produce plastic parts in the injection molding process, it is typically constructed from hardened steel, aluminum, and other alloys. An injection mold is composed of a series of parts that allows molten plastic to be cooled and form the desired shape. Steel molds are usually more expensive to build, but have a longer service life, which will offset the higher initial cost compared to the greater number of parts manufactured before wear.

Difference Between Die Casting Mold and Plastic Injection Mold

The structure of die casting mold is similar to that of plastic mold. The main difference between die casting mold and plastic mold is that on the feed gate sleeve, the gate sleeve of the plastic mold is a slender taper, and the diameter of the inlet is relatively small; while the inlet of the die casting die is relatively large. 

1. The injection pressure of the die casting mold is large, so the die is required to be relatively thicker to prevent deformation

2. The gate of the die casting mold is different from that of injection mold, so a shunt cone is needed to decompose the high pressure of the material flow.

3. The core of the die casting die does not need quenching, while the general injection mold should be quenched above HRC52.

4.  Generally, the die-casting die cavity shall be nitrided to prevent the alloy from sticking to the die cavity.

5.  Generally, the corrosion of the die casting die is relatively large.

6.  Compared with the injection mold, the clearance of the movable fitting part of the die-casting mold (such as core pulling slider) is larger, because the high temperature in the die casting process will cause thermal expansion. If the gap is too small, the die will be stuck.

7.  The parting surface matching requirements of die casting die are higher, because the fluidity of alloy is much better than that of plastic. It is very dangerous for high temperature and high pressure material flow to fly out of the parting surface.

8.  Generally, the injection mold can be vented by a parting surface. The die casting mold must be provided with an exhaust slot and slag collection bag.

9.  Die casting mold injects faster, plastic injection is divided into several stages. 

10.  The die casting mold consists of two halves. The product structure of different plastic molds is different.

11.  Plastic molds and die-casting molds are made of different steels. Plastic molds generally use 45# steel, T8, T10, and other steel, while die-casting molds mainly use heat-resistant steel such as 3Cr2W8V.