Comparison of Investment Casting with Other Metal Casting Processes

There are many types of casting processes on the market, each with their own advantages and disadvantages. Here we compare investment casting with 6 metal casting processes. To help you make an informed decision, we've outlined the pros and cons of some of the most common casting processes below in detail.

Investment Casting Vs Sand Casting

Due to the nature of the process, investment castings can be held to much tighter tolerances than sand castings or forgings. This can be important and can avoid machining or other finishing operations. Investment casting offers near net-shape, thus reducing costly machining time.  Investment casting is also capable of more reliable castings with much thinner walls than sand castings. Due to the thinner wall capability, investment castings produce substantially less scrap rates and lighter weight castings. Investment castings, in general, provide a much higher percentage of defect free-castings.

An example of this is the conversion of neck rings for glass container manufacture from sand to investment casting. The near net shape that is achieved with the neck rings outweigh the costs incurred through the less precise and less efficient process of sand cast.

Investment Casting Vs Die Casting

In comparison to die casting, investment casting offers a wider range of alloys that can be investment cast, such as stainless steel alloys. Investment castings are also a great alternative for lower production volume projects that are not feasible for die castings due to high tooling costs.  Tooling costs for investment castings are much lower, especially when made in-house by Franklin Bronze. Die casting also requires more maintenance than investment casting as die castings quickly wear.

Investment Casting Vs Permanent Mold

Permanent mold casting is the only non-destructive casting method on this list. Unlike investment casting, shell molding or greensand casting, molds in permanent mold casting are reused again and again. Instead of using sand or refractory material to build up mold walls, permanent molds are generally made of steel or cast iron.

Tolerances and surface finish for permanent mold casting lie somewhere between shell molding and greensand casting. None of these methods approach the dimensional accuracy and surface finish produced by investment casting.

For high volume runs, permanent mold casting is often the most economically viable option, but for low or medium volume runs, tooling costs are often prohibitive. Despite high initial tooling costs, labor costs for permanent mold casting are lower than other casting methods.

Since permanent molds, themselves, are made from metals, their melting points create limitations. Metals cast in permanent molds must have significantly lower melting points than the metals making up the mold. Therefore, permanent mold casting is often employed using aluminum or other non-ferrous alloys.

Investment Casting Vs Plaster Mold

Plaster molding is a casting process with similarities to sand casting. Instead of using sand in the process, a mixture of water, gypsum and strengthening compounds are used. Plaster molding delivers a smooth, as-cast finish, but it requires a minimum of a 1-degree draft. It is also a more expensive process when compared to permanent mold and sand casting. In addition, this method may require the frequent replacement of plaster molding materials.

Investment casting offers a flexibility in design and is a useful process for casting alloys that are difficult to machine. Investment casting methods also allow for complex shapes, intricate core sections, finer details and thinner walls.

Investment Casting Vs Metal Forging

Investment casting does not have the expensive tooling costs as seen with forgings. In forged parts, there is also an issue of non-uniform internal stresses and parting lines, neither present with investment cast parts. Forging is also typically a much more expensive metal forming process than investment casting.

Investment Casting Vs Metal Fabrication

Metal fabrications are metal structures produced by cutting, bending, and welding multiple pieces of material together. This method produces increased steps and results in a higher scrap rate. The increase in wasted materials, along with increased labor time, causes metal fabrications to be expensive and time-consuming.

A fine-tuned Investment casting method can cut down labor time while providing a continuous part that delivers a clean and consistent look to the end-user. The reduction of labor time also reduces lead times and all applicable costs. Casting consistency can also lead to lower scrap rates, which can lower your overall metal fabrication costs even further. 

Besser Investment Casting Solutions

We specialize in providing customized casting solutions to customers around the world. Contact us for more information on our investment casting method or request a quote today.

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