Investment Casting VS Die Casting

Casting is an engineering technique that dates back to 1838. However, much has changed about the process. Only a few modern machines have taken over to make the process more automated with faster production of casting parts.

Some of the methods used include Investment casting and die casting. The two processes are standard and almost similar. Besides, specific differences exist between investment castings and die casting. However, you can take advantage of a casting process that works well for you once you identify the difference.

In this article, we will discuss these distinguishing differences so that you have the advantages and disadvantages of the casting processes.

But first,

Investment Casting Process

The investment casting process is where wax makes a prototype of the part you want to cast. However, to prepare a hollow ceramic mold, the prototype is continuously dipped into a ceramic liquid to achieve the required thickness before it hardens.

Once the ceramic liquid dries and hardens, you melt the wax and leave the ceramic mold.

The parts can now be cast by pouring the molten metal into the ceramic cavity mold and left to solidify. Once the molten material has dried, the ceramic mold gets destroyed, leaving the casted metal part.

Once the process is successful, the metal casting equipment undergoes finishing by removing excess metal on the surface. Moreover, numerous tests ensure the cast parts meet the required standards.

Die Casting Process

This casting procedure is where molten metal material is forced through a mold cavity under pressure to form a cast product or part. The molten material is allowed to dry, and then it is removed from the casting equipment.

However, the casting equipment is generally made of stainless steel metal to withstand the pressure of the molten material injected through them.

Besides, you can use the molded cast equipment repeatedly to produce many parts before replacing them. Nevertheless, the process varies depending on the molten material used to make the cast parts.

That is why there is a hot chamber die casting process and a cold section die casting process.

So,

How do you determine the casting process that fits your project?

The two casting processes are similar. However, each casting project requires a different casting method. Nevertheless, the following factors determine the difference between investment castings and die casting.

a. The Shape Design

Investment casting prepares complex designs that require internal details. You can take advantage of the investment casting flexibility to add any interior design of small shapes and thin walls of the parts.

However, it is impossible to add any internal modification of a cast part while using die casting. The other advantage of die casting is that it is a better process for parts that require good dimensional results. Again die casting works well for items that do not need detailed, intricate designs.

b. The Material Used

There exists a difference in investment casting and die casting based on the material used. Mainly two types of metals are used. These are ferrous and non-ferrous materials.

Ferrous material works well with investment casting. The materials include Zinc, Stainless Steel, and copper.

Die casting works mainly with non-ferrous metals like copper, aluminum, magnesium, lead, pewter, and tin-based alloys.

c. Size of the Part

When you compare the size of the cast part, you will realize that the investment casting process can produce pieces that range from low ounces to high limits.

This makes the process limited by the size of the wax pattern. Remember, it is essential to securely gate the design because of the repeated dipping in the ceramic material.

However, die casting works well for large productions with high-volume items. Moreover, die casting will produce items that are repeatedly excellent and consistent.

d. Production Costs

The costs involved between the two processes largely depend on the types of equipment used. Investment casting involves high capital involvement in designing the casting equipment.

Moreover, the equipment used produces parts of excellent surface finish with high superior dimensions. That means to achieve parts that meet these standards will require expensive casting equipment.

However, die casting does not require expensive pieces of equipment like of investment casting. On the contrary, the disadvantage of die casting is that it requires many secondary finishing, pushing the expenses slightly high.

Nevertheless, die casting is cost-effective when dealing with high-volume runs. But if you are looking to create large parts from stainless steel, then investment casting is cheaper.

e. The End Product Requirement

To determine the difference between die casting and investment casting, we consider the final requirements of the product. Investment casting produces parts that have superior and excellent surfaces that require no secondary finishing.

Moreover, you can achieve the dimensional requirements of thinner walls with higher tolerance by using the investment casting process.

Unlike die casting, the final product may have a smooth surface finish, but the ultimate outcome will require secondary machining and finish achieving superior surfaces.

f. Tolerance 

If you are looking to produce smaller parts with high dimensional accuracy but have a high tolerance, consider investment casting.

While die casting may produce good dimensional parts, it only fits large parts that, in most cases, lose dimensional accuracy during production.

Therefore, die casting will create low tolerance with low dimensional accuracy hence low tolerant cast parts.

g. Duration of the Process

Investment casting requires more time input to produce and make the ceramic molds. This also requires more hands in creating shapes. Moreover, the involvement of human labor invests in casting a slow process because of the slow nature of human beings.

On the contrary, the die casting process is faster than investment casting. Moreover, it is possible to automate the whole process without using human labor in the production process.

That means the cast parts can be made by machines, making the volume of production go higher within a short time.

Conclusion

Consider the above factors and decide when to use the investment casting and when applying the die casting process is ideal. The two processes might look similar, but their applications vary when carrying out different metal projects. For any service needed regarding investment casting or die casting, contact us.