Choosing the most appropriate casting process requires taking into account the design requirements as well as the economics of each possible route. Because the casting method has an impact on yields, part design, and secondary finishing operations, it is often an iterative process. A better understanding of the advantages of each method aids in the reduction of the number of options and the saving of time.
Sand casting, permanent mold casting, and die casting are the three most common methods for producing aluminum parts that are close to net shape. Those last two are frequently misunderstood or conflated. We'll compare them here, as well as identify the advantages of die casting aluminum and permanent mold casting along the way.
die casting services VS. PERMANENT MOLD CASTING
Steel molds are used in both permanent mold and die casting to form a cavity that holds the molten aluminum while it cools. Unlike sand casting, where a new cavity is formed in the sand with each cycle, the processes use molds to achieve their results. Die coatings protect the steel from the abrasive effect of molten metal during the forging process.
The primary difference between the two steel die techniques is the manner in which the metal is introduced into the tooling. Permanent mold casting is a process in which metal flows into the cavity of the mold from a reservoir. A gate regulates the flow rate in order to reduce turbulence. Typically, the die will be designed to fill from the bottom or side, with the riser at the highest point.
After the metal has been filled, it is allowed to cool before the mold is opened and the part is removed. Inserts are inserted into the mold before it is closed, allowing for the creation of features such as internal galleries.
In contrast to gravity-fed permanent mold casting, metal is forced into the cavity of a die casting cavity under pressure. As a result, it is very similar to the process of plastic injection molding. As with permanent mold casting, once the metal has solidified, the mold is opened and the cast forms are removed.
ADVANTAGES OF die casting mold
- The as-cast surface has an excellent finish, with a finish better than 125 microinches.
It is possible that secondary machining and finishing will be minimal.
- Can maintain extremely tight geometric tolerances, even when working with thin walls.
- Because it is a faster process part-to-part than permanent mold casting, unit costs are lower on longer runs.
- Equipment typically requires less floor space than permanent mold casting equipment. It is more important to the caster than to the casting buyer, but it may also help to lower overhead costs that are allocated on the basis of the amount of space occupied.
ADVANTAGES OF PERMANENT MOLD CASTING
- Permanent mold dies are generally less complex and therefore less expensive than die casting defects causes and solutions dies.
In most cases, the surface finish is in the range of 125 to 300 microinches, which means that secondary machining is not always necessary.
- Because this process produces less porosity than China die casting manufacturer, the yield of finished parts will be higher.
- Castings are more durable.
CONSIDER THE VOLUME AND PART CHARACTERISTICS OF THE PART
The speed of permanent mold and die casting makes it cost-effective to invest in metal mold tools when producing large quantities. zinc alloy die casting tools are generally more expensive than permanent die tools, but the process produces a more accurate part with thinner walls and smoother surfaces than the former.
The permanent mold process is a little slower than die casting, but the tools are less expensive. Additionally, and this is frequently a deciding factor, the resulting parts are stronger and have less porosity.