While admittedly casting and forging are both really good ways to shape metal, the two processes are not alternatively applicable under certain circumstances and under certain conditions.
In other words, the two metal shaping techniques are not interchangeable. They are applied under different situations appropriate for their respective purposes.
The type of metal shaping technique to be used will essentially and usually depend on the particular metal part needed to be shaped.
Before going into the nitty-gritty of the two methods, we must first understand what they are.
Casting can be roughly defined as a process that is generally done by melting off metal in order for it to be shaped and molded into its desired form.
This is done by heating up the metals, usually ingots, in very high temperatures until it completely morphs from its solid form to its liquid state.
While in this liquid state, it will be easier to manipulate the metal. The molten metal will be poured into pre-prepared molds and then left for some time to enable the metal to take the shape of its template.
There are many different types of castings. These include Investment Castings, Sand Castings, and Die Castings.
On the other hand, forging is a process by which hot or cold materials are heated until they reach very high temperatures sufficient for them to malleable enough to be easily worked on.
This metal fabrication process, like casting, use heat in order for the metal to be altered to the desired shape.
The good thing about castings is that they require less expensive equipment, in contrast to metal forgings. This makes castings generally more affordable.
Casting also produces more defined and more refined parts than what metal forging produces. This is why castings will be the better option for when the specific part required needs ultimate precision.
Casting is also the better choice for when the desired end result calls for the production of materials containing cavities and/or hollows.
However, in the same way that all things have their own shares of pros and cons, castings also have a disadvantage.
Generally, products of metal casting exhibit more surface porosity than its forged counterparts. Also it is not as tough and as resistant as forged metals.
But then again, castings done by skillful manufacturers and/or workers can manipulate and develop metal and alloy combinations to perfect and improve the strength and durability of the part.
An advantage metal forging is that the resulting products of this process are usually dense and very mechanically strong and durable.
Moreover, the products of metal forging are very resistant to wear and tear due to their inherent strength.
But while this is the case, the disadvantage however of metal forging is that it can create few defective cavities in the finished product, especially if it was not done right or if the forger lacked sufficient skill needed in the complicated process of forging.
There is a higher level of danger that comes naturally from manual forging; in the same way, the materials or specialty equipment needed for modern era forging are also very expensive. This causes forged metals to be slightly more costly than castings.
