Investment casting and MIM are both near-net-shape processes for complex metal parts. The choice is primarily driven by part size, volume, and required precision.
Head-to-head comparison:| Factor | Investment Casting | MIM |
|---|---|---|
| Part size range | 1 g - 25 kg+ | 0.1 - 50 g |
| Typical volume | 100-10,000 parts/run | 5,000-500,000+/yr |
| Tolerance (as-processed) | ±0.5% of dimension | ±0.3% of dimension |
| Surface finish | Ra 3.2-6.3 µm | Ra 1.6-3.2 µm |
| Tooling cost | $3k-15k (wax die) | $5k-30k (steel mold) |
| Tooling lead time | 4-8 weeks | 6-14 weeks |
| Per-part cost (10 g, 5,000/yr) | $1.50-3.00 | $3-6 |
| Per-part cost (10 g, 50,000/yr) | $0.80-1.50 | $0.50-1.20 |
| Material options | Very wide (Al, Cu, steel, superalloys, Ti) | Wide (stainless, steel, Ti, Inconel, Cu) |
| Process speed (first article) | 6-10 weeks | 10-16 weeks |
- Choose investment casting when: parts are larger than 50 g, volumes below 10,000/year, material is aluminum or copper, or the part requires non-ferrous alloys that MIM cannot process
- Choose MIM when: parts are under 20 g, volumes exceed 20,000/year, tight tolerances (±0.3%) are required, or thin walls (under 1 mm) are needed