+91 91 57 58 59 11
Survey No.76/ P4, Nh.27,Wandheshwar-Bhunava Road, At. BHUNAVA.360311,Ta. Gondal, Dis. RAJKOT

Alloy Steel vs Carbon Steel: What to Select for Your Investment Cast Products

blog img
Alloy Steel vs Carbon Steel: What to Select for Your Investment Cast Products

Foundry experts will tell you alloy steels are more challenging to cast than carbon steels, but this shouldn’t influence your choice of metal. In fact, investment casting alloy steel yields bigger benefits than using the same process for carbon steel. If this seems like a contradiction, the explanation lies in understanding the benefits of investment casting.

The Difference Between Alloy and Carbon Steel

Steel is iron containing between 0.0002 and 2.1% carbon. Such carbon steels carry the 10XX designation under the SAE classification system, where XX represents the carbon percentage. These steels have good strength and ductility, making them suitable for a range of applications. In addition, steel with a carbon content of around 0.2% has good machinability too.

Alloy steels are those where additional elements are incorporated. Manganese, nickel, silicon and chromium are some of the most common. When the proportion of alloying elements is between 5 and 20% of the total the resulting high alloy steel is considered a tool steel.

Unlike carbon steels, alloy steels are readily hardened and/or toughened by heat treatment. However, they are more challenging to machine and to cast, with specifics depending on the actual alloy composition.

Benefits of Investment Casting

Investment casting works well for steel parts. This is because the ceramic molds handle the high temperatures involved, and the process yields near net shape geometries that need little final machining.

Molds are made by coating a wax pattern with a ceramic slurry. This is built up in layers, and layer thickness is used as a way to control solidification rate. Once the slurry is dry, the wax is melted out to leave the cavity. The ceramic shell that remains may be heated to reduce its chilling effect on molten metal as it’s poured in.

Investment casting is capable of producing fine detail and thin sections. Surface finish is a reflection of the original wax pattern with the addition of granularity from the slurry. Using a very fine slurry for the first layer helps create a smooth finish on the cast part.

Geometric accuracy is very good. Investment casting can typically maintain tolerances of better than 0.005

Translate >>