Die casting is an essential manufacturing process that involves injecting zinc and aluminum ( molten metal with low melting points) into the die-cast mold and letting it cool. It happens under two different mechanisms ( cold and hot chamber casting). However, it depends mainly on the melting points, and it's used for making complex and straightforward metal parts.
You need to have enough knowledge about die casting before you outsource to companies or use the process because it requires a unique approach. This article will do Justice to that by explaining the meaning, types, benefits, and applications.
Die casting is the process where molten metals are injected into a steel mold at high pressure (1,450-30,500ps) and allowed to cool to form the shape in the mold. It is then removed to produce a fabricated part or casting. Casting ensures products have uniform parts , good dimensional accuracy, and overall a good surface finish. It is most times used in creating several copies of an original piece.
The two industrial die casting techniques are cold chamber, and hot chamber die casting. Each has unique characteristics and can be used in various situations. The two different sorts of processes are described below:
When working with materials that have a high melting point, like aluminum, cold chamber die casting is the ideal technique. As the high temperature required to melt the material can harm the pumping system, this procedure is ideal for such metals.
Before being injected into the die, the melted material is ladled into a cool chamber. A cold chamber process uses a hydraulic system similar to a hot chamber method. However, a higher pressure of between 2000 and 20000 psi might be necessary.
The hot chamber die casting process is best, when working with materials with low melting points, such as zinc, tin, lead, and magnesium alloy. It is not appropriate for alloys with greater melting points since doing so would harm the pump because the metal would come into direct contact with it. It entails applying pressure from a hydraulic system to inject the metal into the die after it has melted.
The common procedure for hot or cold chamber die casting includes pushing molten metal under intense pressure into a die mold. The complex die casting process steps are listed below:
Clamping is done at the initial stage of die casting. It is done to improve injection and the removal of the solidified product, lubricate the die and clean it to remove any impurities. After lubrication and cleaning, clamp the die and apply considerable pressure to shut it.
Put the metal you want to inject into the shot chamber after melting it. Depending on the method you choose, there are different steps. For instance, in the cold chamber die casting, the shot chamber is cold, whereas in the hot chamber die casting, it is hot. After that, use a hydraulic system to create high pressure to inject the metal into the die.
Allow the metal to cool and solidify while clamped. The material will take on a shape that is identical to the mold's design once it has solidified.
An ejection mechanism will push the solid casting out of the die after the die mold has been unclamped. Before ejecting the finished product, be sure that it has properly solidified.
This is the last stage, and it entails getting rid of extra metal from the finished product's sprue and runner. It is possible by using a trim die, saw, or other tools. In the procedure, the removed metal components are recyclable and useful.
Die casting employs non-ferrous alloys with robust mechanical characteristics. The low melting point and the robust mechanical characteristics are attributed to the non-ferrous moiety. The quality of the final part depends on the materials used. As a result, there are no restrictions when selecting a material. However, the following are the list of common alloys:
Due to their distinctive qualities, aluminum alloys can be used to create a wide variety of products. On the one hand, aluminum alloy 380.0 is the most often used material in die casting due to its special qualities. Aluminum alloys 360, 390, and 413 are a few other alloys. These are some of the characteristics of aluminum that make it suitable for die casting:
● outstanding resistance to corrosion
● High conductivity of electricity
● Outstanding finishing qualities
● Complete recycling
● Corrosion-resistance
● It maintains excellent dimensional stability.
Zinc alloys are solid, resilient, robust, perform well, and are economical. Because of their superior and competitive qualities to those of other alloys like aluminum, magnesium, and bronze, they play a significant role in the die casting process.
You can employ a variety of zinc alloys. However, Zamak #2, #3, #5, #7, ZA8, and ZA27 are the most popular zinc die casting materials and are known for the following qualities:
● Enhancing Castability
● Reduced Cycle Time Increased Ideal Mechanical Properties for Die Life
A good surface finish that will support the diecast's durability, protection, or aesthetic effect is required. Die cast parts can be finished using a variety of techniques. However, the size of the cast parts and the metal you choose will determine your options.
The most popular and effective method of surface treatment is painting. You could do it for aesthetic or additional protection reasons. With particular attention paid to the metal used, lacquers, paints, or enamel are applied during the procedure. Clean the metal surface to eliminate contaminants like oil (this also improves adherence), and add a base coat (primer), followed by the primary paint.
This surface finishing method is commonly used with zinc casting, giving the cast an antique appearance. After being electroplated with copper or other alloys, the casting is covered with a colorful substance, such as copper sulfide. The casting is treated to prevent tarnishing after being relieved (i.e., certain colored layers are removed to reveal the copper layer beneath).
The electroless or electroplating procedures of plating are suitable and affordable methods for completing die casts. The layer of finish is thin, similar to the ceramic coating option. Therefore, you must first prepare the surface before utilizing it.
Instead of using electricity to plate a diecast item, electroless plating uses chemicals. The die-cast component is submerged in a substance with reducing qualities. The chemical deposits itself on the die cast after being catalyzed by other minerals.
You can use the die casting process to produce various parts and components that are utterly distinctive and incredibly useful. Here are a few uses for the process:
● Manufacturing of both industrial and consumer goods
Consumer goods like sink faucets, compressor pistons, connector rods, heat sinks, etc., can be produced using this method.
● Production of automobile goods
The procedure is utilized to create more specialized parts required in the automotive sector, such as gear, cylinders, mini engines, gladhands, and transfer cases.
● Production of aeronautical components
Die casting is an economical way to make exceptional metal components that are light and meet the demanding standards of the aerospace industry.
Due to its low manufacturing costs and simplicity of use, die casting is a crucial metal fabrication technology. However, employing the method has additional advantages. The benefits of die casting are listed below:
● You can make intricate pieces.
● You can produce multiple parts without the requirement for assembly.
● Reduction of labor expenses
● Narrower tolerances
● Quick production cycles
● Use of recyclable materials
Die casting often has minimal production costs. However, several things affect the price. Here are a few to consider while choosing the most cost-effective solution for your diecast project:
The cost of die casting is significantly influenced by the materials you use. Some materials are expensive to purchase. Despite appearing irregular, the cost of die casting ingredients is also generally rising.
Die casting, and tooling costs are two of the three key determinants of production cost. The cost of the tooling might be significant, depending on the production methods, technological approach, mold manufacturing process, and maintenance.
The manufacturing procedure employed affects the mold's price. For instance, the advantages and capabilities of CNC machining will contribute to a high mold cost.
Die casting is crucial in manufacturing sheet metal valued for its productivity and efficiency. Although the procedure is straightforward, it may require much knowledge or experience, making outsourcing to the right business, like ours, a better course of action. At Ares Prototyping, you have access to a group of skilled engineers who specialize in die casting services. Due to the collective experience of our staff, we can offer you greater advice regarding the ideal die-casting method for your project.
We have a lot of manufacturing plants and cutting-edge equipment to make high-quality parts. With our quick turnaround time, you may upload a design file and receive a quote and DfM analysis in as little as 12 hours.