Anyone who wants to assess a quotation needs to know what it consists of. With MIM parts that is not obvious: the price is made up of six blocks that behave very differently — some scale with weight, some with batch size, some not at all.
This article breaks down a typical unit price and identifies where you actually have influence. The short version first: the biggest lever is not in purchasing but in design.
The six blocks
The reference case is a part of the kind typically enquired about: 20 grams, 17-4 PH, medium complexity, 200,000 pieces per year, eight-cavity tool.
| Cost block | Share | Scales with |
|---|---|---|
| Feedstock | 25 – 35 % | part weight and material |
| Injection moulding | 15 – 20 % | cycle time ÷ cavity count |
| Debinding and sintering | 20 – 30 % | furnace occupancy, i.e. volume |
| Post-processing | 10 – 20 % | number of operations |
| Quality assurance | 5 – 10 % | inspection scope and documentation |
| Tool amortisation | 5 – 15 % | annual volume and lifetime |
The ranges are real. A titanium part with AMS passivation and PPAP level 3 distributes completely differently from a simple steel part from running series.
Feedstock — the material costs what it weighs
MIM feedstock is not metal powder but a mixture of powder and binder — and markedly more expensive than bar stock. Guide values per kilogram of feedstock:
| Material | Guide price feedstock |
|---|---|
| FN02 / FN08 (low-alloy) | EUR 15 – 30/kg |
| 316L / 17-4 PH | EUR 25 – 45/kg |
| Tool steels M2, D2 | EUR 40 – 70/kg |
| Ti-6Al-4V | EUR 150 – 300/kg |
| Inconel, W alloys | from EUR 200/kg |
Important for the calculation: not only the part costs material, the sprue does too. Cold-runner tools produce 8 to 12 percent sprue. The material is recycled, but not entirely and not cost-neutrally.
Injection moulding — cavity count decides
The machine hourly rate lies between EUR 60 and 110. What matters is how many parts each cycle produces. A cycle time of 25 seconds yields roughly 1,150 parts per hour from an eight-cavity tool — and 144 from a single-cavity tool.
That makes cavity count the second-largest lever after weight. The amortisation calculation is in K.05.
Debinding and sintering — the underestimated block
This step is energy-intensive and slow: sintering furnaces run 12 to 18 hours at 1,250 to 1,380 °C. Costing is by furnace occupancy, that is by the volume your parts take up on the sintering plates.
This has a consequence that surprises many: a flat, bulky part costs more to sinter than a compact one of the same weight, because it occupies more plate area. Designing parts so that they pack densely lowers this block noticeably.
Post-processing — every operation costs
As a rule of thumb per additional operation: EUR 0.03 to 0.12 per part, depending on how far it can be automated.
- Deburring and vibratory finishing: usually unavoidable, low
- Sizing: for individual tight dimensions, medium
- Heat treatment: often required for 17-4 PH, medium
- Passivation to AMS 2700: medical, high
- Machining rework: the most expensive variant, avoid
The last point is the single most expensive item of all. One dimension that has to be turned or milled can raise the unit price by 15 to 30 percent — because the part has to be clamped, machined, cleaned and inspected all over again.
Quality assurance — what the drawing demands
A series part with sample inspection costs a few cents here. A part with documented 100-percent inspection, batch traceability and a PPAP level 3 package lies well above that. What a MIM PPAP comprises is in K.06.
Tool amortisation — distributed or one-off
Either you pay for the tool once, or it is distributed across the unit price. Both are customary; we state it separately so that cash flow stays visible. At EUR 45,000 for the tool and 200,000 parts over three years, that is EUR 0.075 per part.
The five levers
Sorted by effect — the first moves more than the following four combined.
| Lever | Effect | Who decides |
|---|---|---|
| Part weight | very high | design |
| Cavity count | high | volume and tool budget |
| Number of rework operations | high | design and drawing |
| Tolerances and surfaces | medium to high | drawing |
| Material | medium | requirement profile |
Weight is the lever. It acts threefold: on feedstock, on furnace occupancy and on cycle time. Ten percent less material typically lowers the unit price by 6 to 9 percent — without changing anything about function. Where material can be saved is covered in K.02.
Tolerance is the silent cost driver. An over-tight dimension forces sizing or machining and thereby pushes up two blocks at once. The model calculation — a 38 percent cost lever — is in K.11.
What cannot be negotiated
For completeness, because it saves time:
- The material price. Feedstock is a commodity with a world market price. For titanium and nickel-base alloys it fluctuates considerably.
- Sintering duration. Physics, not a matter for negotiation.
- Inspection cost in regulated applications. What ISO 13485 or IATF 16949 require, they require.
Negotiable, by contrast, are volume brackets, call-off quantities, stockholding, and whether the tool is paid once or through the unit price.
Our approach
We state tooling, unit price and maintenance provision separately — not as a service promise, but because a blended calculation makes comparing two quotations impossible. The guide-price calculator gives you the order of magnitude in advance, without an enquiry and without a call-back.
Further reading
- Calculating tooling cost realistically — cavity count, family moulds and amortisation.
- Cpk-ready tolerancing — why ±0.02 mm doubles part cost.
- Tooling lock-in and requalification — what a supplier switch really costs.