Sand Casting vs Investment Casting: Key Differences

Both sand and investment casting shape molten metal into parts, but they differ in mold materials, cost, and precision. Sand casting uses a disposable sand mold, while investment casting creates a ceramic shell from a wax pattern.

Sand casting is cheaper and faster for large, simple parts like engine blocks and pump housings. Mold preparation is quick, but surface finish is rough (Ra 50–500 µm) and dimensional tolerances are loose (±1–5 mm). It works well for low to medium volumes of ferrous and nonferrous metals.

Investment casting is more expensive but delivers near-net shape with excellent surface finish (Ra 1.5 µm) and tight tolerances (±0.1–0.5%). The wax pattern is coated with ceramic, then melted out, allowing complex geometries, thin walls, and undercuts without secondary machining. Common for turbine blades, medical implants, and jewelry.

Choose sand casting when economy and size matter; choose investment casting when precision and complexity are critical. The decision also depends on production volume—sand casting suits larger runs with lower per-part cost, while investment casting is ideal for small to medium runs requiring high accuracy.

#RapidTooling# #VacuumCasting#