There are tons of materials used in construction. Some of them come already prepackaged. However, for others, you may have to create them yourself. The differences in the nature of these materials mean that the process of creating them might also be distinct. In this article, we consider the differences between casting and forging, two methods that are quite popular.
What is Casting?
Casting is the process of heating material, metal, for instance, until it liquefies. To help make it easier, imagine it to be like heating a candy bar. You then transfer this liquefied material into a mold. Once it cools, the liquid would take the shape of the mold, creating whatever shape you had in mind.
Different types of casting exist. These types depend on the nature of the materials you use and simple variations in the techniques. However, for the most part, you employ the same idea of heating and cooling of the material. Some of these types include sand casting, die casting, investment casting, and so on.
This process is quite beneficial if you are looking to mass-produce an item. Once you create one mold, you can replicate the same shape the number of times you want. This eliminates the drudgery associated with doing the same thing repeatedly and saves cost, too.
Do understand that eventually, the metalworker (if that is you) will have to finish the product. Depending on the specifications of the client, you may have to do this by hand. This results in added labor – you should pay attention, especially if you tire easily.
Advantages of Casting
● Heating metals makes them malleable, giving you the means to create a variety of shapes.
- Equipment used in casting is always available, as opposed to other alternative measures.
- Casting results in products that are close to clients’ specifications. In essence, the time spent in finishing the product is often small.
- Cast parts are not often very strong, at least not as strong as forged products.
- Casting requires constant supervision. If you are the metalworker, you will need to be on hand to monitor the process closely. This is much more required for certain types of casting such as plastic or investment casting.
What is Forging?
Forging is a material-production process that also relies heavily on heat. However, the difference between this method and casting is that the heat is not so intense as to melt metal. The material – usually metal – is heated up just enough to make it easy for the metalworker to manipulate it.
Once the piece of metal gets to the favored temperature, you can then use a hammer or die to hit it into the required shape. Thus, the primary job here is to deform and reshape the metal into the desired form. In addition, you may also employ forging to eliminate defects and porosity in the product.
You can forge materials at different stages of temperature. The first is when you heat the metal to just about room temperature. This is known as cold forging. The next is warm forging, and here the product is heated to above room temperature. If you go further to increase the heat to recrystallization temperature, you are then carrying out hot forging.
Advantages of Forging
- Forged products are longer lasting. Hence, they are ideal for building strong structures.
- You will hardly experience shrinkage or porosity with the finished product. This is because the process used in forging eliminates the chances of that happening.
- The process is cost-saving because it is not labor-intensive or requires a lot of materials.
- You may have to do a lot of post-forging finishing to meet any specific client requirement.
- This process is closed off; it doesn’t give room for a lot of experimentations.
- If the metal is an alloy, it would be challenging to forge. This is because the metal remains solid even when heated.
Differences Between Casting and Forging
As we’ve shown above, each method has its upsides and weaknesses. In this section then, we will be highlighting key areas they diverge.
Forged products are often stronger (and thus more durable) than their cast counterparts. A cast object is more likely to shatter when it comes in contact with another object, unlike forged ones. This difference is tied to the divergent construction process of both methods. When a metal is hit and hammered, its grain gets stretched. A consequence of this is longer durability.
2. Size Limitations
Size limitations can hamper forging. It is a lot harder altering a metal’s shape using the process. Also, at certain thicknesses, you may be unable to forge some metals. However, that is not the case with casting. Here, you simply pour the melted liquid into the desired mold. Voila, you have the desired shape! As a result of this, a metalworker can forge a material of whatever thickness.
It is advisable to engage forging when creating uniform products. This is because the process is straightforward, leaving no room for creating complex outputs. However, with casting, as long as you can create a mold for it, you can craft products of any complexity.
This is the converse of the point discussed above. One drawback with casting is that the products are not always uniform. Forging, on the other hand, is suitable for creating consistency and uniform shapes.
Although both processes are relatively cheap, casting is more cost-effective.
Which Should You Settle For?
Generally, the two processes are unique and are thus useful for different purposes. Before settling for any method, you may want to consider the use you intend for the final product. Similarly, it’d be a great idea to pay attention to the costs of both processes. Finally, consider the expertise of the metalworker in question.
In this article, you will find a detailed summation of the differences between forging and casting. The discussion begins by giving you an overview of both processes, highlighting their strengths and drawbacks. With the information here, you surely will be better empowered to make better choices.