What is precision casting?
What is precision casting?
Precision casting (also called investment casting, lost-wax casting,and cire perdue) is a metal shaping technique to form near net-shaped products. The basic casting principle is to pour and to fill molten metal into a disposable ceramic mold. Then, the molten metal adapts to the shape of the mold and forms the final products. The technique has been around for thousands of years, as far as the bronze age. Even though it sounds like an old trick, but the research and development is still going up to this day. Even today, the casting foundries keep working to continuously improve the quality of casting products. Therefore, precision casting is one of the longest running advanced metal-shaping technology in human history. This article helps understanding: What is precision casting?
How does the process work?
The core process of precision casting are mold making and metal casting. In Zenith Allmart Precisindo, we recycle and reuse our waxes and excess metal parts during manufacturing. So, we always optimize our material loop within our foundry.
Mold making
- First, create wax patterns as models for the final products. Then, assemble the wax patterns to make wax pattern trees. Following this, assemble the wax pattern trees form metal delivery system and increase the casting efficiency.
- Next, dip the wax pattern trees into ceramic slurry, so ceramic shells coat the wax pattern trees. The ceramic shells adapt the shape of the wax pattern trees and form disposable ceramic molds. Later, dry the molds.
- Repeat the dipping to increase the thickness of ceramic shells because thicker shells provide higher mold strength. After the first layer, apply stucco to the ceramic shells.
- Remove the waxes from the molds (lost-wax). So, this de-waxing leaves negative cavities for later metal filling.
- Following de-waxing, fire the molds before the metal casting. Firing burns residual waste within the molds, sinters the molds,and pre-heats the molds for the subsequent metal casting.
Metal casting
- Melt metal above the melting temperature. Meanwhile, control and monitor the furnace temperature.
- If necessary, add alloying elements and slag-catchers to control the chemical composition of the molten metal.
- Pour the molten metal to fill the mold. Eventually, let the metal solidify. Also control cooling rate to control the micro-structure.
- After the cooling, break molds and cut excess parts. Finally, retrieve the metal as-cast product.
Machining stage and finishing stage follow the metal casting to result in final product. Precision casting minimizes these stages because the as-cast product shape is already near net-shape of the final product. A succeeding article has been published about gating system of precision casting.
Why is precision casting or lost-wax casting important?
In general, precision casting or lost-wax casting is a manufacturing solution to tackle industrial challenges. The design flexibility of this casting technique allows the manufacture of a wide variety of products, ranging in sizes and shapes. Moreover, this technique is even more relevant nowadays, because a great deal of products requires an intricate shape with high dimensional tolerance and repeatability. On top of that, the smooth surface of the as-cast products is an added value of precision casting or lost-wax casting.
Machining stage is one of the most tiresome processing stages in the manufacturing industry, if not being the most. Fortunately, the shape of investment casting or lost-wax casting product is near net-shaped. For this reason, the application of this manufacturing technique can minimize the machining stage and the cost for machining, material lost, and labor work.
How about the precision casting or lost-wax casting in Zenith Allmart Precisindo?
Zenith Allmart Precisindo employs a team of experts with 20 years of experience in precision casting/lost-wax casting industry. We have cast a wide variety of products, from a small medical implant to a large impeller. Also, our technology allows us to produce orders in small, medium, and large volume. Please check our portfolio here to learn more about our company products!
Zenith Allmart Precisindo is more than merely your metal casting supplier or vendor. We want to grow together with you, and we will solve your manufacturing challenges using our advanced technology, professional practice, and manufacturing knowledge. Contact us here for more information!
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